Electrostatic Separator of Cannabis Trichomes: An Innovative Approach to Extraction

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Traditional methods, such as mechanical sieving and solvent-based extraction, have problems with purity, yield, and environmental impact. This paper explores the application of electrostatic separation as a novel, sustainable, and efficient method for isolating cannabis trichomes. A new concept for a free-fall electrostatic separator for cannabis trichomes is proposed. The technique and equipment minimize the need for manual labor, allowing the separation of cannabis trichomes to a desirable purity. The separator is scalable from 1 to 100 kg/hour and can be fully automated. Glandular trichomes dry separation separability free-fall electrostatic cannabis Figures Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 1. Introduction Cannabis trichomes are glandular structures that play a crucial role in the quality and potency of cannabis products. The function of glandular trichomes is to secrete complex metabolites and phytochemicals, such as terpenoids, phenylpropanoids, flavonoids, etc., which are accumulated in trichome heads. As a result, trichomes contain large amounts of secondary metabolites, which are valuable for the pharmaceutical and nutraceutical industries. The separation of trichomes from plant biomass is an extremely important industrial operation. One method to separate glandular trichomes from plant biomass is wet fractionation through mechanical agitation of plant flowers in ice water (Delp, 2000). Ice water causes the resins to become brittle, while the remaining plant material remains more flexible, which allows separation based on the difference in specific gravity. The drawback of the ice-water method is the loss of some valuable aromatic components, such as terpenes and light oils, in the water. Another drawback of this method is the need for subsequent drying to avoid fungal propagation. These drawbacks of wet separation may lead to the alteration/degradation of organoleptic properties of trichomes. Another method of separation is dry fractionation, based on the tumbling or sieving of the plant biomass to screen out glandular trichomes (Watts & Amovick, 2019). The method requires pre-freezing of plant biomass with a liquid freezing agent, such as liquid CO 2, with the next separation on the centrifuge, using the difference in density between trichome heads and plant matter. The disadvantage of this method is that the process is extremely sensitive to operating parameters such as temperature, humidity, and process duration. To get the high-purity product, a cold dry atmosphere and a short processing time are required. However, under these conditions the yield is low. An increase in yield causes a loss of purity, which requires further product purification from contaminants. Another method of dry separation, so-called “static tech”, is based on triboelectric charging of dried plant biomass (Philips, 2022). The method requires manual mechanical rubbing of dry plant powder on the nylon sift screen. Due to the different chemical compositions, the plant biomass and trichomes are getting different charges, which allows the hand-pick collection of trichome heads with nitrile gloves or parchment paper. However, this method is labor-intensive and not scalable. Also, the separation of trichomes from trichome-bearing plant material is not very selective, which affects product purity. It is commonly recognized that this method of separation requires highly trained personnel to correctly use this technique for different grades of plant biomass to reach the desirable quality and purity of the product. In summary, current methods for cannabis trichome separation involve mechanical processes, which can damage delicate trichomes, reduce cannabinoid and terpene content, or introduce contaminants. The separation technique should be improved to minimize mechanical damage to trichomes and improve the separability of dry plant matter. At the same time, the “static tech” technique revealed the difference between the electrical properties of trichomes and plant biomass, attracting attention to electrostatics as a possible alternative. Historically, electrostatic separation has roots in mineral processing, where it plays a crucial role in separating conductive and non-conductive minerals. Early adopters found it invaluable in industries where traditional wet separation techniques were either impractical or economically unfeasible. It was demonstrated that electrostatic separators could achieve high-purity separations, paving the way for broader industrial applications (Inculet, 1985). The agricultural sector also benefited from electrostatic separation technologies (Harmond et al., 1961). Farmers and processors utilized these systems to clean and separate grains, seeds, and other agricultural products from soil, stones, and husks. These early applications highlighted the versatility of electrostatic separation and its ability to cater to industries requiring dry processing methods. Electrostatic separation technology is based on the differences in surface chemistry, electrical conductivity or dielectric properties. The fundamental principles of electrostatic separation are charging particles and mechanical separation by using electrical, centrifugal, and gravitational forces or their combination. All electrostatic separators contain a system to charge particles, an externally generated electric field for separation, and a system to convey particles in and out of the separation apparatus. Electrical charging can occur by one of multiple methods including conductive or non-conductive induction, triboelectric charging, and corona charging. The separation occurs on an electroconductive rotating drum, or electroconductive belt, or by free falling between two parallel plates in the strong electric field. A rotating drum electrostatic separator is preferable for separating particles with different electrical conductivity. Multiple variations and geometries are used for conductive drum separators, but they generally operate on similar principles. Feed particles are dispersed onto a rotating drum that is electrically grounded and then charged by either induction or corona discharge. The separation is based on the differences in discharge time. Electroconductive particles quickly give up their charge to the surface of the grounded drum. The rotation of the drum creates centrifugal force which, in combination with gravitational force, leads to the early departure of these particles from the surface of the drum to the primary bin. In contrast, non-conductive particles retain their electrical charge, which will keep them attracted to the drum surface. Eventually, they will be brushed from the surface in a secondary bin. In some applications, several intermediate bins are introduced between primary and secondary bins. For example, Jordan et al. (1951) described the essential elements of a rotating drum electrostatic separator as a feeder, stationary discharge electrode, and rotating electroconductive drum. The separation occurs due to the different trajectories of charged particles depending on their dielectric properties. This method, however, does not work for the plant powder mix, because of similar electrical conductivity and high adhesion of fine particles to each other rather than to the surface of the rotating electrode. Moreover, electrification of the plant powder mix results in opposite charges for trichomes and plant biomass. Electrostatic forces between oppositely charged fine particles are stronger than the effect of external electric force. This creates a problem of clogging particles of different kinds, which makes further separation impossible. The clogging problem is addressed by free-fall electrostatic separation, where fine particles are suspended in the air in a diffused state. A method of free-fall separation of fine particles in an electric field is described by Rajabzadeh et al. (2015). The principle of free-fall electrostatic separation is based on the difference in particle charge, which determines their free-falling trajectory in the unidirectional electric field. During triboelectric charging, particles accept different amounts of charge (positive or negative), depending on their chemical composition. During the separation process, the trajectories of the individual particles are influenced by the Coulomb force. Particles are then separated from the mixture based on the amount of acquired charge. Xing et al. (2020) used the difference in electrical properties of protein and starch for the electrostatic separation of yellow pea protein in a free-fall bench separator. The advantage of a free-fall electrostatic separator is related to minimal particle-particle interaction. Unfortunately, conventional free-fall separators are unsuitable for trichome separation due to the high acquired charge and sticking of particles to each other. An increase in the flow rate results in decreased purity of the desirable product. Another limitation of conventional free-fall electrostatic separators is low throughout, which limits their applications for trichome separation from trichome-bearing plant material. Electrostatic separation of trichomes is difficult due to heterogeneous feedstock and small differences between cannabis trichomes and plant biomass. Hence, the design of electrostatic separators for cannabis trichomes presents a challenge and significant innovation. This challenge could be mitigated by preliminary triboelectric charging of cannabis trichomes. The theory of triboelectric charging of micron-sized particles is well-developed mostly for pharmaceutical powders (Ghory and Conway, 2018). Triboelectric charging of pharmaceutical powders was explored with advanced experimental techniques, including direct observation with atomic force microscopy (Bunker et al., 2007). Matsusaka et al. (2010) reviewed recent developments in triboelectric charging of powders, considering different mechanisms of particle charging, such as contact charging, charge relaxation, wall friction, repeated impacts of a single particle, and particle charging in gas-solids pipe flow. The triboelectric charging of micron-sized particles conveyed pneumatically through the high-velocity circular pipe was analyzed through numerical simulation (Lawn, 2025). Although the method to triboelectrically charge the particles is simple and easy, the charge transfer depends on the environmental conditions, such as temperature and humidity, which should be controlled in a certain range. Triboelectric charging is widely used as a precursor in the electrostatic separation of particles. A typical electrostatic separator contains a cyclone or rotating vibrator for the mechanical separation of particles (Bendimerad et al., 2014). Triboelectrically charged particles enter the electrostatic separator where a DC electric field is applied. The trajectory of the particles in a free-fall electrostatic separator depended on the electrostatic charge and mass of the particles. For example, Wang et al. (2014) used electrostatic charging of plant biomass for electrostatic fractionation of proteins and carbohydrates. The particle trajectories are deflected in the electric field according to the polarity and the amount of charge (Wang et al., 2015). One of the challenges of free-fall electrostatic separators is related to the use of planar electrodes, resulting in particle-electrode collision and a decrease in separation efficiency. To mitigate this problem, Eddine et al. (2025) proposed a segmented electrode design. Also, a non-homogeneous electric field in this design facilitated the deflection of oppositely charged particles, improving the separation efficiency. This paper examines the particle charge of trichomes, principles of electrostatic separation of trichomes, system design, and the advantages and challenges associated with this technique. 2. Particle charge In our experiment, we used samples of ground cannabis material with different volumetric fractions of trichomes. The electric charge of samples was measured in a Faraday cage using a Keithley 6517B (Tektronix Inc., Beaverton OR, USA) electrometer. The measurement setup is shown in Fig. 1 . All measurements have been done under a temperature of 15 o C and relative humidity of 30–34%. The Faraday cage was made of two aluminum cylinders, separated by a dielectric material, creating a cylindric capacitor with 2.4 nF capacitance. An internal cylinder of 1” diameter was filled either with plant biomass or trichome material for charge measurements. The charge was calculated from the voltage readings, using the formula: $$\:Q=CV$$ Charge measurements showed a linear correlation between sample charge and volumetric fraction of trichomes. Plant biomass had a positive charge, while samples with trichomes had a negative charge ranging from 20 to 100 pC. The charge was temperature-dependent, decreasing to 0 at -18 o C. Hence, electrostatic separation should be done at room temperature. It was also found that triboelectric charging of the sample by friction on the nylon sieve increased the negative charge of trichome heads and induced a positive charge on the stalk and chlorophyll-contained leafy fraction. The correlation between cannabinoid content and the charge was observed even before the decapitation of trichomes. Therefore, electric charge could be a reliable indicator of the cannabinoid content in raw material. The nature of electric charge could be related to the chemical composition of plant biomass (Wang et al., 2015). Trichomes are mostly acidic while trichome-bearing plant material is mostly carbohydrates. This difference in electric charge allows the separation of trichome fraction in a strong electric field, using Coulomb forces. However, it should be noted that efficient separation requires decapitation and additional charging of the mixed powder. To substitute the manual operation of triboelectric charging on a nylon sieve, we explored the corona charging of grounded cannabis samples by the ionic wind (Fig. 2 ). It was found that charging plant biomass by the ionic wind did not change the negative charge of trichomes but induced a positive charge on the stalk and chlorophyll-contained leafy fraction. This difference can facilitate the electrostatic separation of trichomes from trichome-bearing plant material. These electrical properties determine the different behaviour of particles in an electric field and separability in free-falling mode. Key equations governing the motion of particles in an electrostatic field include Coulomb’s law and Newton’s second law, which determine the force exerted on charged particles and their subsequent acceleration, respectively. The equations provide a framework for optimizing separator designs for specific materials and applications. The next section analyses fundamental forces, acting on the particles in electrostatic and aerodynamic fields. The calculation of forces, acting on typical cannabis powder, allows evaluation and ranges them according to their effect on the particles. 3. Fundamental forces To understand fundamental forces, acting on free-falling particles in an electrostatic field, it is important to know the electric properties of particles. Along with electrical conductivity and natural charge, polarizability or acquired charge plays an important role. Polarizability will determine the electric force, acting on the particle F e , while density will determine gravitational force F g . The size of the particle will determine the buoyancy force F b . We also need to consider particle-particle interaction F p-p , which will depend on the particle charges. Negatively charged particles will attract positively charged particles and repel the particles of the same polarity. A schematic picture of all acting forces is shown in Fig. 3 . Assuming the spherical shape of the charged particle, the electric force in the electrostatic field F e is determined as: $$\:{F}_{e}=qE=4\pi\:{r}^{2}{\rho\:}_{e}E$$ where \(\:r\) is the particle effective radius, m; \(\:{\rho\:}_{e}\) is a specific charge, C/m 2 ; and \(\:E\) is electric field strength, V/m. Considering the typical size of a particle as 200 µm and a specific charge of 0.26 µC/m 2 (Wang et al., 2014) in the electrostatic field 3×10 5 V/m, the force \(\:{F}_{e}\) ~10 − 6 N. For smaller particles 70 µm, the electric force decreases tenfold to 10 − 7 N. Gravitational force F g depends on material density \(\:{\rho\:}_{m}\) : $$\:{F}_{g}=mg=\frac{4}{3}\pi\:{r}^{3}{\rho\:}_{m}g$$ There is almost a threefold difference in density between heads and stalk \(\:{\rho\:}_{heads}\) =308 kg/m 3 and \(\:{\rho\:}_{stalk}\) = 118 kg/m 3 , determining the difference in gravitational force. The gravitational force for heads is estimated as (0.12…0.005) ×10 − 7 N, while for stalks it is (0.04…0.002) ×10 − 7 N. Buoyancy force F b depends on the particle velocity \(\:\upsilon\::\) $$\:{F}_{b}=\frac{1}{2}{\rho\:}_{a}{C}_{D}A{\upsilon\:}^{2}$$ where \(\:A\) is a particle cross-sectional area, m 2 , \(\:{\rho\:}_{a}\) is the air density, kg/m 3 , and \(\:{C}_{D}\) is a drag coefficient, for laminar flow equal to ~ 1.5. $$\:{F}_{b}=\frac{1.5}{2}\pi\:{r}^{2}{\rho\:}_{a}{\upsilon\:}^{2}$$ For a velocity of 0.1 m/s, the estimate of the buoyancy force is ~ 3×10 –10 N, significantly smaller than the electric and gravitational forces. The particle-particle force F pp depends on the particle's charge \(\:{q}_{1}{,\:q}_{2}\:\) and described by Coulomb's law: $$\:{F}_{pp}={k}_{e}\frac{{q}_{1}{q}_{2}}{{d}^{2}}$$ where \(\:d\) is the distance between particles, m; and \(\:{k}_{e}\) is an electrostatic constant ( \(\:{k}_{e}\) = 8.99 ×10 9 N/m·C 2 ). Considering the average particle charge of 20 pC and the distance between particles 1 mm, the estimated particle-particle force is about 3.6×10 − 6 N. This value is comparable with the electrostatic force, indicating its significant role in clustering. This force could be smaller if the particles with opposite charges are uniformly distributed. In this case, the mechanical scattering of particles with a narrow diffusor could minimize the interaction effect. In summary, the two dominant forces are the electric force from the external electric field F e and particle-particle force F pp . The separability of material \(\:\varvec{S}\) depends on the ratio between two forces: $$\:S=\frac{{F}_{e}}{{F}_{pp}}$$ The electrostatic separator was designed to maximize \(\:\varvec{S}\) by minimizing the effect of particle-particle interaction and maximizing the impact of the applied electric field. The process of hash separation is schematically shown in Fig. 4 . Particles are separated based on their trajectories, which depend on their mass, charge, and interaction with the electric field. Conductive particles quickly lose charge upon contact with grounded surfaces, while non-conductive particles retain their charge longer, enabling effective separation. Dry plant biomass is non-conductive. The particles with a negative charge (mostly trichomes) are attracted to the positive electrode, while particles with a positive charge (mostly stalk) are attracted to the negative electrode. After accumulation on electrodes, these fractions are scrapped into separate bins. A part of the material did not acquire charge or stick in the conglomerate. This part goes through the separation chamber into the recycle bin and could be further fractionated by recirculation in the loop. The fraction of trichomes in the recycle bin indicates the efficiency of separation or separability. The electric force is controlled by high voltage, applied between two electrodes. The flow rate of the material is controlled by an airflow regulator a vacuum control device. 4. System design A basic electrostatic separator unit consists of a feeder, charging system, separation chamber, collection system and control system. Figure 1 shows a separation chamber with a triboelectric charging system which consists of air compressor 1, vibrating feeder 2, airflow regulator 4, and coiled pipeline 5. The ground cannabis material with particle size in the range from 20 to 300 microns is manually or automatically supplied to vibrating feeder 2 and then pneumatically introduced by airflow to the coiled pipeline 5. The powder supply is controlled by airflow regulator 4, which may be manually controlled or actuated through an electronic signal. Triboelectric charging of particles occurs in the coiled pipeline ( 5 ). Due to the different chemical composition, plant biomass particles acquire a positive charge, while trichomes acquire a negative charge. Immediately after triboelectric charging in the pipeline, charged particles are injected into the separation cabinet through a diffuser ( 6 ) with a narrow (about 3 mm) opening. Further separation of trichomes from the plant material is based on the difference in their electrostatic charge. Particles fall in the strong electric field between two electroconductive plate electrodes ( 10 ). The electrodes are oppositely charged from a high-voltage power supply 7, controlled through the control unit 8. The high-voltage source provides an electric field inversely proportional to the distance between electrodes. Both electrodes 10 are insulated using dielectric material 11 to prevent an electrical arc to the grounded metal frame of the separation chamber. Both electrodes are secured to the top of the frame. Non-parallel orientation of electrodes is necessary to create a higher gradient of electric field at the inlet, decreasing downstream the pathway of charged particles. A higher electric field at the inlet applies additional force on the charged particles, resulting in distortion of their trajectory from a vertical free-falling path. Downstream the electric field is decreasing, which results in the attraction of negatively charged particles to the positively charged electrode, while positively charged plant material is attracted to the negatively charged electrode. Uncharged or lost charge plant material falls into collection bins 9. The innovation is based on the ability of an electrostatic separator to isolate the trichomes from plant biomass based on their unique electrochemical properties. It should be noted that electrostatic separation is not sensitive to the initial concentration of trichomes in plant material and could work with different grades of plant biomass. The spiral configuration of the feeding pipeline allows distributed and uniform exposure of the entire volume of the plant mixture to triboelectric charging. The turbulent regime of dry air prevents the clogging of charged particles. The ability of particles to acquire the charge can be regulated by the degree of throttling of a vibrating dispenser. The diffusor with a narrow lateral nozzle provides better diffusion of particles in air volume between electrodes, which increases their exposure to the electric field during settling in the gravitational field. Long vertical electrodes provide sufficient exposure of particles to the electric field and therefore, a better separation effect. The trichomes are collected directly from the surface of the charged electrode. However, the manual collecting of trichomes limits the throughput capacity of the electrostatic separator. This deficiency could be eliminated by introducing self-cleanable electroconductive electrodes. Self-cleanable electrodes contain a moving electroconductive belt, a rotating part, a mechanical drive (motor), and a transmission. The speed of the belt is determined by the accumulation rate of charged particles on the belt surface and controlled by the motor. This design of electrodes will allow full automation of the separation and collection of trichomes. 5. Experimental validation Cannabis plants Morccan Baño collected from the field were dried to a moisture content of 0.06–0.15 g/g dry matter. Dried flowers were separated from stems, stalks, and branches using manual or mechanical methods. Dry plant biomass containing glandular trichomes was sifted using a rotary vibrating sieve or similar device with an upper 250-micron stainless steel mesh and a lower 74-micron mesh screen. The result is a powder colloquially known as kief or hash. It contains glandular and other types of trichomes, pistils, trichome stalks, pollen, dirt, and fine particles of plant material with particle size distribution from 10 to 300 microns. The dry powder was further sifted on a 250 and 74-micron screen. Initial mechanical treatment on the sieve resulted in the detachment and liberation of most of the glandular trichome heads from the attached stalk, which is critical for further electrostatic separation, mostly determining yield and product purity. Once the trichomes were liberated, they were processed in the electrostatic separator. The powder is fed into the device, controlling for optimal performance, air flow rate, position and angle of electrodes, temperature, humidity, and powder feed rate. Two fractions are created—a heads fraction containing mainly glandular trichome heads and a tails fraction containing mainly undesired contaminants. Powder that did not manage to separate is immediately reprocessed until all powder is separated. Fractions were checked under a microscope to evaluate purity and to determine the nature of the purity or contaminants. If feasible, heads and/or tails are returned to the vibrating screen for further liberation. Fractions were periodically examined under a microscope to determine if liberation was complete. This process can be repeated as necessary to achieve the desired purity. The final product is ready for post-processing or sold as a final product. The comparison with conventional methods showed a first-pass average purity of 40–50%, and 50–60% if using a Resinator. In contrast, the electrostatic separation with Plasmastatic achieved a first-pass purity of 80–95% round trichomes with 98% achievable in 2 or more passes. 6. Advantages of Electrostatic Separation Compared to conventional wet and dry fractionation, electrostatic separation of cannabis trichomes offers multiple advantages. High Purity Enables the selective isolation of trichomes with minimal contamination from plant material. Moreover, purity could be improved by fine-tuning electrostatic and aerodynamic fields. Another option is multiple recirculation of the material. In the first run, the trichome fraction could be partially (up to 5%) contaminated with the plant biomass. This material with a purity of 90–95% could be used for medicinal and cosmetic purposes. For special purposes, an electrostatic separator allows further purification to 99.8% due to multiple cycles or multiple separation stages. Non-Destructive Due to the minimal mechanical action, it preserves the integrity of trichomes. Short processing time preserves the quality of bioactive compounds. Oxidation of plant material could be further reduced by electrostatic separation in an oxygen-free environment (for example, helium or nitrogen). Solvent-Free Eliminates the need for chemical solvents, reducing environmental impact and production costs. Also, solvent-free technology minimized the damage of trichomes and the escape of water-soluble bioactive compounds. Scalability Suitable for both small-scale and industrial applications. The separation rate of Plasmastatic is 2 kg/hour; but can be scaled to 100 kg/hour or more. It could be achieved due to increased surface of the electrode system, adjustment of particle flow rate, or a parallel/series combination of basic electrostatic units. The number of electrostatic separation units connected in parallel can achieve the desired throughput separation capacity. With the series configuration of basic electrostatic separation units, the higher purity of the product could be achieved. Due to extremely low energy consumption, electrostatic separators could be integrated with renewable energy sources, such as solar or wind energy in remote locations or mobile applications. Energy Efficiency It is a non-thermal technology, requiring much less energy compared to traditional methods like solvent extraction. The total energy used for the pilot-scale electrostatic separation is about 20W for the separation throughput of about 100 grams per minute. The energy efficiency of electrostatic separators is increasing with the increase of processing capacity tons per hour. Challenges and Limitations Despite high upfront investment for equipment and system setup, electrostatic separator requires minimal maintenance costs. However, the operation requires trained operators to manage the process and troubleshoot issues. The initial preparation stage requires precise drying, grinding and liberation of trichomes from the cannabis material. Also, the electrostatic separator must meet regulatory compliance for safety and quality standards in the cannabis industry, which could differ in different countries. International patents protect the proprietary design of electrostatic separators. The good news is that the first models of electrostatic separators of cannabis trichomes have been on the market since 2023 under the brand “Plasmastatic” and are commercially available from SC Filtration (www.sambocreeck.com). Conclusions Electrostatic separation technology has the potential to revolutionize the cannabis extraction industry by providing a cleaner and more efficient method for trichome isolation. By leveraging differences in electrical properties, this technique offers a high-purity, environmentally friendly, and scalable solution for cannabis extraction. As the industry grows, adopting innovative technologies like electrostatic separation will be key to meeting the demand for high-quality cannabis products while minimizing environmental impact. Future research should focus on optimizing system design, improving throughput, and integrating this technology with downstream processing methods. Additionally, advancements in material science and electric field modelling could further enhance separation efficiency and scalability. Declarations Funding Declaration No external funding for this research was obtained. Author Contribution Charles MacGowan: Conceptualization, Project administration, Concept verification, Prototype design, Prototype testing, Writing – review & editing. Alex Martynenko: Conceptualization, Methodology, Theoretical analysis, Experimental research, Writing - original draft, Writing – review & editing. Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper. Data Availability Data will be made available on request. Ethics, Consent to Participate, and Consent to Publish declarations Not applicable Consent to Participate Declaration Not applicable References Delp RC. (2000). Method and apparatus for extracting plant resins. US Patent 6,158,591, Priority from 1998-02-24. Watts JE, Amovick TJ. (2019). Rotary separation apparatus and process. US Patent 10,512,938 B2, Priority from 2017-12-05. Philips T. (2022). 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Cite Share Download PDF Status: Published Journal Publication published 04 May, 2025 Read the published version in Journal of Cannabis Research → Version 1 posted Editorial decision: Revision requested 07 Apr, 2025 Reviews received at journal 01 Apr, 2025 Reviewers agreed at journal 31 Mar, 2025 Reviews received at journal 28 Mar, 2025 Reviewers agreed at journal 25 Mar, 2025 Reviewers invited by journal 24 Mar, 2025 Submission checks completed at journal 24 Mar, 2025 First submitted to journal 23 Mar, 2025 You are reading this latest preprint version Research Square lets you share your work early, gain feedback from the community, and start making changes to your manuscript prior to peer review in a journal. As a division of Research Square Company, we’re committed to making research communication faster, fairer, and more useful. We do this by developing innovative software and high quality services for the global research community. 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Also discoverable on Platform About Our Team In Review Editorial Policies Advisory Board Help Center Resources Author Services Accessibility API Access RSS feed Manage Cookie Preferences © Research Square 2026 | ISSN 2693-5015 (online) Privacy Policy Terms of Service Do Not Sell My Personal Information {"props":{"pageProps":{"initialData":{"identity":"rs-6033072","acceptedTermsAndConditions":true,"allowDirectSubmit":false,"archivedVersions":[],"articleType":"Research Article","associatedPublications":[],"authors":[{"id":433682444,"identity":"40e3f5a7-9674-4f35-9a2c-53f42b331018","order_by":0,"name":"Charles MacGowan","email":"","orcid":"","institution":"Sambo Creeck Filtration","correspondingAuthor":false,"prefix":"","firstName":"Charles","middleName":"","lastName":"MacGowan","suffix":""},{"id":433682445,"identity":"bda3e3b7-a5e6-4d81-a6c4-feee24dd8dbc","order_by":1,"name":"Alex Martynenko","email":"data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAZAAAAAyAQMAAABI0h/eAAAABlBMVEX///8AAABVwtN+AAAACXBIWXMAAA7EAAAOxAGVKw4bAAABAUlEQVRIiWNgGAWjYDACdhTeAQY5hgPMDfi1MENpHqgWY4YDjCRqSWwgpIW/mfmYBGOOXb69RO7BxwVnbNL7jh9sYPhRg1uLxGG2ZAPGbcmWPRJ5ycYzbqTlzjyT2MDYcwyPNYd5DB8wbmM24JHIMZPm+XA4d8OBxAZmBjbcOuQP8384wLitHqTF/DdQS7rB+YdALf9wazE4zMMItOUw2BZmnhuHEwxuAG1hbMOtxfAwm7FB4rbjBjxn3hhL85xJM5x542HDwd4+3Frkjjc/k/i4rdqAvT3H8DPPMRt5vvPJBx/8+IbH+yCQACIEEhACBwhogAJ+ItWNglEwCkbByAMA0nVTn3rc2IUAAAAASUVORK5CYII=","orcid":"","institution":"Dalhousie University","correspondingAuthor":true,"prefix":"","firstName":"Alex","middleName":"","lastName":"Martynenko","suffix":""}],"badges":[],"createdAt":"2025-02-14 20:23:07","currentVersionCode":1,"declarations":"","doi":"10.21203/rs.3.rs-6033072/v1","doiUrl":"https://doi.org/10.21203/rs.3.rs-6033072/v1","draftVersion":[],"editorialEvents":[{"content":"https://doi.org/10.1186/s42238-025-00281-z","type":"published","date":"2025-05-04T15:57:11+00:00"}],"editorialNote":"","failedWorkflow":false,"files":[{"id":79247439,"identity":"d99dddcd-26e8-47c6-b691-18aff5d318d5","added_by":"auto","created_at":"2025-03-26 07:17:52","extension":"jpg","order_by":1,"title":"Figure 1","display":"","copyAsset":false,"role":"figure","size":169518,"visible":true,"origin":"","legend":"\u003cp\u003eCharge measurement with Keithley 6517B electrometer (1) and Faraday cage (2)\u003c/p\u003e","description":"","filename":"1.jpg","url":"https://assets-eu.researchsquare.com/files/rs-6033072/v1/7a614524af54baf29605e12b.jpg"},{"id":79248645,"identity":"7afd760f-82f0-4d7e-bc9b-2facccd05aa8","added_by":"auto","created_at":"2025-03-26 07:33:52","extension":"png","order_by":2,"title":"Figure 2","display":"","copyAsset":false,"role":"figure","size":814293,"visible":true,"origin":"","legend":"\u003cp\u003eCorona charging of plant biomass\u003c/p\u003e","description":"","filename":"2.png","url":"https://assets-eu.researchsquare.com/files/rs-6033072/v1/eefc5d4ee2306dad731fcd58.png"},{"id":79247440,"identity":"a1facf12-afb8-4e83-848a-ddc3e8335ff6","added_by":"auto","created_at":"2025-03-26 07:17:52","extension":"png","order_by":3,"title":"Figure 3","display":"","copyAsset":false,"role":"figure","size":18529,"visible":true,"origin":"","legend":"\u003cp\u003eForces, acting on the charged particle in the electrostatic field\u003c/p\u003e","description":"","filename":"3.png","url":"https://assets-eu.researchsquare.com/files/rs-6033072/v1/57f7745c9b47f91ce543be80.png"},{"id":79248500,"identity":"b343f194-1fb0-4b60-b0d4-d69d42f071e0","added_by":"auto","created_at":"2025-03-26 07:25:52","extension":"jpg","order_by":4,"title":"Figure 4","display":"","copyAsset":false,"role":"figure","size":28031,"visible":true,"origin":"","legend":"\u003cp\u003eThe principle of trichome separation in the electrostatic field.\u003c/p\u003e","description":"","filename":"4.jpg","url":"https://assets-eu.researchsquare.com/files/rs-6033072/v1/d8cfc3fce1275e577694f670.jpg"},{"id":79247441,"identity":"103378e3-d4b3-4cf5-a1bb-67a00cc23b31","added_by":"auto","created_at":"2025-03-26 07:17:52","extension":"jpg","order_by":5,"title":"Figure 5","display":"","copyAsset":false,"role":"figure","size":132705,"visible":true,"origin":"","legend":"\u003cp\u003eA sketch of a basic electrostatic separation unit\u003c/p\u003e\n\u003cp\u003e1. Air compressor\u003c/p\u003e\n\u003cp\u003e2. Vibrating feeder\u003c/p\u003e\n\u003cp\u003e3. Separation chamber\u003c/p\u003e\n\u003cp\u003e4. Airflow regulator\u003c/p\u003e\n\u003cp\u003e5. Coiled pipeline\u003c/p\u003e\n\u003cp\u003e6. Flow straightener (diffuser)\u003c/p\u003e\n\u003cp\u003e7. High-voltage power source\u003c/p\u003e\n\u003cp\u003e8. Control unit\u003c/p\u003e\n\u003cp\u003e9. Collection bins\u003c/p\u003e\n\u003cp\u003e10. Electroconductive plate electrodes\u003c/p\u003e\n\u003cp\u003e11. Insulators\u003c/p\u003e","description":"","filename":"5.jpg","url":"https://assets-eu.researchsquare.com/files/rs-6033072/v1/0063bbefd29f2ea3e072ff9e.jpg"},{"id":81988199,"identity":"7debb1a7-2280-494b-a567-a39f7f0c6024","added_by":"auto","created_at":"2025-05-05 16:08:14","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":1909819,"visible":true,"origin":"","legend":"","description":"","filename":"manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-6033072/v1/5d1af64f-7663-48de-96a6-38c403f4ebf4.pdf"}],"financialInterests":"No competing interests reported.","formattedTitle":"Electrostatic Separator of Cannabis Trichomes: An Innovative Approach to Extraction","fulltext":[{"header":"1. Introduction","content":"\u003cp\u003eCannabis trichomes are glandular structures that play a crucial role in the quality and potency of cannabis products. The function of glandular trichomes is to secrete complex metabolites and phytochemicals, such as terpenoids, phenylpropanoids, flavonoids, etc., which are accumulated in trichome heads. As a result, trichomes contain large amounts of secondary metabolites, which are valuable for the pharmaceutical and nutraceutical industries. The separation of trichomes from plant biomass is an extremely important industrial operation.\u003c/p\u003e \u003cp\u003eOne method to separate glandular trichomes from plant biomass is wet fractionation through mechanical agitation of plant flowers in ice water (Delp, 2000). Ice water causes the resins to become brittle, while the remaining plant material remains more flexible, which allows separation based on the difference in specific gravity. The drawback of the ice-water method is the loss of some valuable aromatic components, such as terpenes and light oils, in the water. Another drawback of this method is the need for subsequent drying to avoid fungal propagation. These drawbacks of wet separation may lead to the alteration/degradation of organoleptic properties of trichomes.\u003c/p\u003e \u003cp\u003eAnother method of separation is dry fractionation, based on the tumbling or sieving of the plant biomass to screen out glandular trichomes (Watts \u0026amp; Amovick, 2019). The method requires pre-freezing of plant biomass with a liquid freezing agent, such as liquid CO\u003csub\u003e2,\u003c/sub\u003e with the next separation on the centrifuge, using the difference in density between trichome heads and plant matter. The disadvantage of this method is that the process is extremely sensitive to operating parameters such as temperature, humidity, and process duration. To get the high-purity product, a cold dry atmosphere and a short processing time are required. However, under these conditions the yield is low. An increase in yield causes a loss of purity, which requires further product purification from contaminants.\u003c/p\u003e \u003cp\u003eAnother method of dry separation, so-called \u0026ldquo;static tech\u0026rdquo;, is based on triboelectric charging of dried plant biomass (Philips, 2022). The method requires manual mechanical rubbing of dry plant powder on the nylon sift screen. Due to the different chemical compositions, the plant biomass and trichomes are getting different charges, which allows the hand-pick collection of trichome heads with nitrile gloves or parchment paper. However, this method is labor-intensive and not scalable. Also, the separation of trichomes from trichome-bearing plant material is not very selective, which affects product purity. It is commonly recognized that this method of separation requires highly trained personnel to correctly use this technique for different grades of plant biomass to reach the desirable quality and purity of the product.\u003c/p\u003e \u003cp\u003eIn summary, current methods for cannabis trichome separation involve mechanical processes, which can damage delicate trichomes, reduce cannabinoid and terpene content, or introduce contaminants. The separation technique should be improved to minimize mechanical damage to trichomes and improve the separability of dry plant matter.\u003c/p\u003e \u003cp\u003eAt the same time, the \u0026ldquo;static tech\u0026rdquo; technique revealed the difference between the electrical properties of trichomes and plant biomass, attracting attention to electrostatics as a possible alternative. Historically, electrostatic separation has roots in mineral processing, where it plays a crucial role in separating conductive and non-conductive minerals. Early adopters found it invaluable in industries where traditional wet separation techniques were either impractical or economically unfeasible. It was demonstrated that electrostatic separators could achieve high-purity separations, paving the way for broader industrial applications (Inculet, 1985).\u003c/p\u003e \u003cp\u003eThe agricultural sector also benefited from electrostatic separation technologies (Harmond et al., 1961). Farmers and processors utilized these systems to clean and separate grains, seeds, and other agricultural products from soil, stones, and husks. These early applications highlighted the versatility of electrostatic separation and its ability to cater to industries requiring dry processing methods.\u003c/p\u003e \u003cp\u003eElectrostatic separation technology is based on the differences in surface chemistry, electrical conductivity or dielectric properties. The fundamental principles of electrostatic separation are charging particles and mechanical separation by using electrical, centrifugal, and gravitational forces or their combination.\u003c/p\u003e \u003cp\u003eAll electrostatic separators contain a system to charge particles, an externally generated electric field for separation, and a system to convey particles in and out of the separation apparatus. Electrical charging can occur by one of multiple methods including conductive or non-conductive induction, triboelectric charging, and corona charging. The separation occurs on an electroconductive rotating drum, or electroconductive belt, or by free falling between two parallel plates in the strong electric field.\u003c/p\u003e \u003cp\u003eA rotating drum electrostatic separator is preferable for separating particles with different electrical conductivity. Multiple variations and geometries are used for conductive drum separators, but they generally operate on similar principles. Feed particles are dispersed onto a rotating drum that is electrically grounded and then charged by either induction or corona discharge. The separation is based on the differences in discharge time. Electroconductive particles quickly give up their charge to the surface of the grounded drum. The rotation of the drum creates centrifugal force which, in combination with gravitational force, leads to the early departure of these particles from the surface of the drum to the primary bin. In contrast, non-conductive particles retain their electrical charge, which will keep them attracted to the drum surface. Eventually, they will be brushed from the surface in a secondary bin. In some applications, several intermediate bins are introduced between primary and secondary bins.\u003c/p\u003e \u003cp\u003eFor example, Jordan et al. (1951) described the essential elements of a rotating drum electrostatic separator as a feeder, stationary discharge electrode, and rotating electroconductive drum. The separation occurs due to the different trajectories of charged particles depending on their dielectric properties. This method, however, does not work for the plant powder mix, because of similar electrical conductivity and high adhesion of fine particles to each other rather than to the surface of the rotating electrode. Moreover, electrification of the plant powder mix results in opposite charges for trichomes and plant biomass. Electrostatic forces between oppositely charged fine particles are stronger than the effect of external electric force. This creates a problem of clogging particles of different kinds, which makes further separation impossible.\u003c/p\u003e \u003cp\u003eThe clogging problem is addressed by free-fall electrostatic separation, where fine particles are suspended in the air in a diffused state. A method of free-fall separation of fine particles in an electric field is described by Rajabzadeh et al. (2015). The principle of free-fall electrostatic separation is based on the difference in particle charge, which determines their free-falling trajectory in the unidirectional electric field. During triboelectric charging, particles accept different amounts of charge (positive or negative), depending on their chemical composition. During the separation process, the trajectories of the individual particles are influenced by the Coulomb force. Particles are then separated from the mixture based on the amount of acquired charge. Xing et al. (2020) used the difference in electrical properties of protein and starch for the electrostatic separation of yellow pea protein in a free-fall bench separator.\u003c/p\u003e \u003cp\u003eThe advantage of a free-fall electrostatic separator is related to minimal particle-particle interaction. Unfortunately, conventional free-fall separators are unsuitable for trichome separation due to the high acquired charge and sticking of particles to each other. An increase in the flow rate results in decreased purity of the desirable product. Another limitation of conventional free-fall electrostatic separators is low throughout, which limits their applications for trichome separation from trichome-bearing plant material.\u003c/p\u003e \u003cp\u003eElectrostatic separation of trichomes is difficult due to heterogeneous feedstock and small differences between cannabis trichomes and plant biomass. Hence, the design of electrostatic separators for cannabis trichomes presents a challenge and significant innovation. This challenge could be mitigated by preliminary triboelectric charging of cannabis trichomes. The theory of triboelectric charging of micron-sized particles is well-developed mostly for pharmaceutical powders (Ghory and Conway, 2018). Triboelectric charging of pharmaceutical powders was explored with advanced experimental techniques, including direct observation with atomic force microscopy (Bunker et al., 2007). Matsusaka et al. (2010) reviewed recent developments in triboelectric charging of powders, considering different mechanisms of particle charging, such as contact charging, charge relaxation, wall friction, repeated impacts of a single particle, and particle charging in gas-solids pipe flow. The triboelectric charging of micron-sized particles conveyed pneumatically through the high-velocity circular pipe was analyzed through numerical simulation (Lawn, 2025). Although the method to triboelectrically charge the particles is simple and easy, the charge transfer depends on the environmental conditions, such as temperature and humidity, which should be controlled in a certain range.\u003c/p\u003e \u003cp\u003eTriboelectric charging is widely used as a precursor in the electrostatic separation of particles. A typical electrostatic separator contains a cyclone or rotating vibrator for the mechanical separation of particles (Bendimerad et al., 2014). Triboelectrically charged particles enter the electrostatic separator where a DC electric field is applied. The trajectory of the particles in a free-fall electrostatic separator depended on the electrostatic charge and mass of the particles. For example, Wang et al. (2014) used electrostatic charging of plant biomass for electrostatic fractionation of proteins and carbohydrates. The particle trajectories are deflected in the electric field according to the polarity and the amount of charge (Wang et al., 2015). One of the challenges of free-fall electrostatic separators is related to the use of planar electrodes, resulting in particle-electrode collision and a decrease in separation efficiency. To mitigate this problem, Eddine et al. (2025) proposed a segmented electrode design. Also, a non-homogeneous electric field in this design facilitated the deflection of oppositely charged particles, improving the separation efficiency.\u003c/p\u003e \u003cp\u003eThis paper examines the particle charge of trichomes, principles of electrostatic separation of trichomes, system design, and the advantages and challenges associated with this technique.\u003c/p\u003e"},{"header":"2. Particle charge","content":"\u003cp\u003eIn our experiment, we used samples of ground cannabis material with different volumetric fractions of trichomes. The electric charge of samples was measured in a Faraday cage using a Keithley 6517B (Tektronix Inc., Beaverton OR, USA) electrometer. The measurement setup is shown in Fig.\u0026nbsp;\u003cspan refid=\"Fig1\" class=\"InternalRef\"\u003e1\u003c/span\u003e. All measurements have been done under a temperature of 15\u003csup\u003eo\u003c/sup\u003eC and relative humidity of 30\u0026ndash;34%.\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003cp\u003eThe Faraday cage was made of two aluminum cylinders, separated by a dielectric material, creating a cylindric capacitor with 2.4 nF capacitance. An internal cylinder of 1\u0026rdquo; diameter was filled either with plant biomass or trichome material for charge measurements. The charge was calculated from the voltage readings, using the formula:\u003cdiv id=\"Equa\" class=\"Equation\"\u003e\u003cdiv format=\"TEX\" class=\"mathdisplay\" id=\"FileID_Equa\" name=\"EquationSource\"\u003e\n$$\\:Q=CV$$\u003c/div\u003e\u003c/div\u003e\u003c/p\u003e \u003cp\u003eCharge measurements showed a linear correlation between sample charge and volumetric fraction of trichomes. Plant biomass had a positive charge, while samples with trichomes had a negative charge ranging from 20 to 100 pC. The charge was temperature-dependent, decreasing to 0 at -18\u003csup\u003eo\u003c/sup\u003eC. Hence, electrostatic separation should be done at room temperature. It was also found that triboelectric charging of the sample by friction on the nylon sieve increased the negative charge of trichome heads and induced a positive charge on the stalk and chlorophyll-contained leafy fraction. The correlation between cannabinoid content and the charge was observed even before the decapitation of trichomes. Therefore, electric charge could be a reliable indicator of the cannabinoid content in raw material.\u003c/p\u003e \u003cp\u003eThe nature of electric charge could be related to the chemical composition of plant biomass (Wang et al., 2015). Trichomes are mostly acidic while trichome-bearing plant material is mostly carbohydrates. This difference in electric charge allows the separation of trichome fraction in a strong electric field, using Coulomb forces. However, it should be noted that efficient separation requires decapitation and additional charging of the mixed powder.\u003c/p\u003e \u003cp\u003eTo substitute the manual operation of triboelectric charging on a nylon sieve, we explored the corona charging of grounded cannabis samples by the ionic wind (Fig.\u0026nbsp;\u003cspan refid=\"Fig2\" class=\"InternalRef\"\u003e2\u003c/span\u003e).\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003cp\u003eIt was found that charging plant biomass by the ionic wind did not change the negative charge of trichomes but induced a positive charge on the stalk and chlorophyll-contained leafy fraction. This difference can facilitate the electrostatic separation of trichomes from trichome-bearing plant material. These electrical properties determine the different behaviour of particles in an electric field and separability in free-falling mode.\u003c/p\u003e \u003cp\u003eKey equations governing the motion of particles in an electrostatic field include Coulomb\u0026rsquo;s law and Newton\u0026rsquo;s second law, which determine the force exerted on charged particles and their subsequent acceleration, respectively. The equations provide a framework for optimizing separator designs for specific materials and applications. The next section analyses fundamental forces, acting on the particles in electrostatic and aerodynamic fields. The calculation of forces, acting on typical cannabis powder, allows evaluation and ranges them according to their effect on the particles.\u003c/p\u003e"},{"header":"3. Fundamental forces","content":"\u003cp\u003e \u003cdiv class=\"BlockQuote\"\u003e \u003cp\u003eTo understand fundamental forces, acting on free-falling particles in an electrostatic field, it is important to know the electric properties of particles. Along with electrical conductivity and natural charge, polarizability or acquired charge plays an important role. Polarizability will determine the electric force, acting on the particle \u003cb\u003eF\u003c/b\u003e\u003csub\u003e\u003cb\u003ee\u003c/b\u003e\u003c/sub\u003e, while density will determine gravitational force \u003cb\u003eF\u003c/b\u003e\u003csub\u003e\u003cb\u003eg\u003c/b\u003e\u003c/sub\u003e. The size of the particle will determine the buoyancy force \u003cb\u003eF\u003c/b\u003e\u003csub\u003e\u003cb\u003eb\u003c/b\u003e\u003c/sub\u003e. We also need to consider particle-particle interaction \u003cb\u003eF\u003c/b\u003e\u003csub\u003e\u003cb\u003ep-p\u003c/b\u003e\u003c/sub\u003e, which will depend on the particle charges. Negatively charged particles will attract positively charged particles and repel the particles of the same polarity. A schematic picture of all acting forces is shown in Fig.\u0026nbsp;\u003cspan refid=\"Fig3\" class=\"InternalRef\"\u003e3\u003c/span\u003e.\u003c/p\u003e \u003c/div\u003e \u003c/p\u003e \u003cp\u003e \u003cdiv class=\"BlockQuote\"\u003e \u003cp\u003eAssuming the spherical shape of the charged particle, the electric force in the electrostatic field \u003cb\u003eF\u003c/b\u003e\u003csub\u003e\u003cb\u003ee\u003c/b\u003e\u003c/sub\u003e is determined as:\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Equb\" class=\"Equation\"\u003e \u003cdiv format=\"TEX\" class=\"mathdisplay\" id=\"FileID_Equb\" name=\"EquationSource\"\u003e\n$$\\:{F}_{e}=qE=4\\pi\\:{r}^{2}{\\rho\\:}_{e}E$$\u003c/div\u003e \u003c/div\u003e \u003c/p\u003e \u003cp\u003e \u003cdiv class=\"BlockQuote\"\u003e \u003cp\u003ewhere \u003cspan class=\"InlineEquation\"\u003e\u003cspan class=\"mathinline\"\u003e\\(\\:r\\)\u003c/span\u003e\u003c/span\u003e is the particle effective radius, m; \u003cspan class=\"InlineEquation\"\u003e\u003cspan class=\"mathinline\"\u003e\\(\\:{\\rho\\:}_{e}\\)\u003c/span\u003e\u003c/span\u003e is a specific charge, C/m\u003csup\u003e2\u003c/sup\u003e; and \u003cspan class=\"InlineEquation\"\u003e\u003cspan class=\"mathinline\"\u003e\\(\\:E\\)\u003c/span\u003e\u003c/span\u003e is electric field strength, V/m.\u003c/p\u003e \u003cp\u003eConsidering the typical size of a particle as 200 \u0026micro;m and a specific charge of 0.26 \u0026micro;C/m\u003csup\u003e2\u003c/sup\u003e (Wang et al., 2014) in the electrostatic field 3\u0026times;10\u003csup\u003e5\u003c/sup\u003e V/m, the force \u003cspan class=\"InlineEquation\"\u003e\u003cspan class=\"mathinline\"\u003e\\(\\:{F}_{e}\\)\u003c/span\u003e\u003c/span\u003e~10\u003csup\u003e\u0026minus;\u0026thinsp;6\u003c/sup\u003e N. For smaller particles 70 \u0026micro;m, the electric force decreases tenfold to 10\u003csup\u003e\u0026minus;\u0026thinsp;7\u003c/sup\u003e N.\u003c/p\u003e \u003cp\u003eGravitational force \u003cb\u003eF\u003c/b\u003e\u003csub\u003e\u003cb\u003eg\u003c/b\u003e\u003c/sub\u003e depends on material density \u003cspan class=\"InlineEquation\"\u003e\u003cspan class=\"mathinline\"\u003e\\(\\:{\\rho\\:}_{m}\\)\u003c/span\u003e\u003c/span\u003e:\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Equc\" class=\"Equation\"\u003e \u003cdiv format=\"TEX\" class=\"mathdisplay\" id=\"FileID_Equc\" name=\"EquationSource\"\u003e\n$$\\:{F}_{g}=mg=\\frac{4}{3}\\pi\\:{r}^{3}{\\rho\\:}_{m}g$$\u003c/div\u003e \u003c/div\u003e \u003c/p\u003e \u003cp\u003e \u003cdiv class=\"BlockQuote\"\u003e \u003cp\u003eThere is almost a threefold difference in density between heads and stalk \u003cspan class=\"InlineEquation\"\u003e\u003cspan class=\"mathinline\"\u003e\\(\\:{\\rho\\:}_{heads}\\)\u003c/span\u003e\u003c/span\u003e=308 kg/m\u003csup\u003e3\u003c/sup\u003e and \u003cspan class=\"InlineEquation\"\u003e\u003cspan class=\"mathinline\"\u003e\\(\\:{\\rho\\:}_{stalk}\\)\u003c/span\u003e\u003c/span\u003e= 118 kg/m\u003csup\u003e3\u003c/sup\u003e, determining the difference in gravitational force. The gravitational force for heads is estimated as (0.12\u0026hellip;0.005) \u0026times;10\u003csup\u003e\u0026minus;\u0026thinsp;7\u003c/sup\u003e N, while for stalks it is (0.04\u0026hellip;0.002) \u0026times;10\u003csup\u003e\u0026minus;\u0026thinsp;7\u003c/sup\u003e N.\u003c/p\u003e \u003cp\u003eBuoyancy force \u003cb\u003eF\u003c/b\u003e\u003csub\u003e\u003cb\u003eb\u003c/b\u003e\u003c/sub\u003e depends on the particle velocity \u003cspan class=\"InlineEquation\"\u003e\u003cspan class=\"mathinline\"\u003e\\(\\:\\upsilon\\::\\)\u003c/span\u003e\u003c/span\u003e\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Equd\" class=\"Equation\"\u003e \u003cdiv format=\"TEX\" class=\"mathdisplay\" id=\"FileID_Equd\" name=\"EquationSource\"\u003e\n$$\\:{F}_{b}=\\frac{1}{2}{\\rho\\:}_{a}{C}_{D}A{\\upsilon\\:}^{2}$$\u003c/div\u003e \u003c/div\u003e \u003c/p\u003e \u003cp\u003e \u003cdiv class=\"BlockQuote\"\u003e \u003cp\u003ewhere \u003cspan class=\"InlineEquation\"\u003e\u003cspan class=\"mathinline\"\u003e\\(\\:A\\)\u003c/span\u003e\u003c/span\u003e is a particle cross-sectional area, m\u003csup\u003e2\u003c/sup\u003e, \u003cspan class=\"InlineEquation\"\u003e\u003cspan class=\"mathinline\"\u003e\\(\\:{\\rho\\:}_{a}\\)\u003c/span\u003e\u003c/span\u003e is the air density, kg/m\u003csup\u003e3\u003c/sup\u003e, and \u003cspan class=\"InlineEquation\"\u003e\u003cspan class=\"mathinline\"\u003e\\(\\:{C}_{D}\\)\u003c/span\u003e\u003c/span\u003e is a drag coefficient, for laminar flow equal to ~\u0026thinsp;1.5.\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Eque\" class=\"Equation\"\u003e \u003cdiv format=\"TEX\" class=\"mathdisplay\" id=\"FileID_Eque\" name=\"EquationSource\"\u003e\n$$\\:{F}_{b}=\\frac{1.5}{2}\\pi\\:{r}^{2}{\\rho\\:}_{a}{\\upsilon\\:}^{2}$$\u003c/div\u003e \u003c/div\u003e \u003c/p\u003e \u003cp\u003e \u003cdiv class=\"BlockQuote\"\u003e \u003cp\u003eFor a velocity of 0.1 m/s, the estimate of the buoyancy force is ~\u0026thinsp;3\u0026times;10\u003csup\u003e\u0026ndash;10\u003c/sup\u003e N, significantly smaller than the electric and gravitational forces.\u003c/p\u003e \u003cp\u003eThe particle-particle force \u003cb\u003eF\u003c/b\u003e\u003csub\u003e\u003cb\u003epp\u003c/b\u003e\u003c/sub\u003e depends on the particle's charge \u003cspan class=\"InlineEquation\"\u003e\u003cspan class=\"mathinline\"\u003e\\(\\:{q}_{1}{,\\:q}_{2}\\:\\)\u003c/span\u003e\u003c/span\u003eand described by Coulomb's law:\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Equf\" class=\"Equation\"\u003e \u003cdiv format=\"TEX\" class=\"mathdisplay\" id=\"FileID_Equf\" name=\"EquationSource\"\u003e\n$$\\:{F}_{pp}={k}_{e}\\frac{{q}_{1}{q}_{2}}{{d}^{2}}$$\u003c/div\u003e \u003c/div\u003e \u003c/p\u003e \u003cp\u003e \u003cdiv class=\"BlockQuote\"\u003e \u003cp\u003ewhere \u003cspan class=\"InlineEquation\"\u003e\u003cspan class=\"mathinline\"\u003e\\(\\:d\\)\u003c/span\u003e\u003c/span\u003e is the distance between particles, m; and \u003cspan class=\"InlineEquation\"\u003e\u003cspan class=\"mathinline\"\u003e\\(\\:{k}_{e}\\)\u003c/span\u003e\u003c/span\u003e is an electrostatic constant (\u003cspan class=\"InlineEquation\"\u003e\u003cspan class=\"mathinline\"\u003e\\(\\:{k}_{e}\\)\u003c/span\u003e\u003c/span\u003e= 8.99 \u0026times;10\u003csup\u003e9\u003c/sup\u003e N/m\u0026middot;C\u003csup\u003e2\u003c/sup\u003e).\u003c/p\u003e \u003cp\u003eConsidering the average particle charge of 20 pC and the distance between particles 1 mm, the estimated particle-particle force is about 3.6\u0026times;10\u003csup\u003e\u0026minus;\u0026thinsp;6\u003c/sup\u003e N. This value is comparable with the electrostatic force, indicating its significant role in clustering. This force could be smaller if the particles with opposite charges are uniformly distributed. In this case, the mechanical scattering of particles with a narrow diffusor could minimize the interaction effect.\u003c/p\u003e \u003cp\u003eIn summary, the two dominant forces are the electric force from the external electric field \u003cb\u003eF\u003c/b\u003e\u003csub\u003e\u003cb\u003ee\u003c/b\u003e\u003c/sub\u003e and particle-particle force \u003cb\u003eF\u003c/b\u003e\u003csub\u003e\u003cb\u003epp\u003c/b\u003e\u003c/sub\u003e. The separability of material \u003cspan class=\"InlineEquation\"\u003e\u003cspan class=\"mathinline\"\u003e\\(\\:\\varvec{S}\\)\u003c/span\u003e\u003c/span\u003e depends on the ratio between two forces:\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Equg\" class=\"Equation\"\u003e \u003cdiv format=\"TEX\" class=\"mathdisplay\" id=\"FileID_Equg\" name=\"EquationSource\"\u003e\n$$\\:S=\\frac{{F}_{e}}{{F}_{pp}}$$\u003c/div\u003e \u003c/div\u003e \u003c/p\u003e \u003cp\u003e \u003cdiv class=\"BlockQuote\"\u003e \u003cp\u003eThe electrostatic separator was designed to maximize \u003cspan class=\"InlineEquation\"\u003e\u003cspan class=\"mathinline\"\u003e\\(\\:\\varvec{S}\\)\u003c/span\u003e\u003c/span\u003e by minimizing the effect of particle-particle interaction and maximizing the impact of the applied electric field. The process of hash separation is schematically shown in Fig.\u0026nbsp;\u003cspan refid=\"Fig4\" class=\"InternalRef\"\u003e4\u003c/span\u003e.\u003c/p\u003e \u003c/div\u003e \u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003cp\u003eParticles are separated based on their trajectories, which depend on their mass, charge, and interaction with the electric field. Conductive particles quickly lose charge upon contact with grounded surfaces, while non-conductive particles retain their charge longer, enabling effective separation. Dry plant biomass is non-conductive. The particles with a negative charge (mostly trichomes) are attracted to the positive electrode, while particles with a positive charge (mostly stalk) are attracted to the negative electrode. After accumulation on electrodes, these fractions are scrapped into separate bins. A part of the material did not acquire charge or stick in the conglomerate. This part goes through the separation chamber into the recycle bin and could be further fractionated by recirculation in the loop. The fraction of trichomes in the recycle bin indicates the efficiency of separation or separability.\u003c/p\u003e \u003cp\u003eThe electric force is controlled by high voltage, applied between two electrodes. The flow rate of the material is controlled by an airflow regulator a vacuum control device.\u003c/p\u003e"},{"header":"4. System design","content":"\u003cp\u003eA basic electrostatic separator unit consists of a feeder, charging system, separation chamber, collection system and control system. Figure \u003cspan class=\"InternalRef\"\u003e1\u003c/span\u003e shows a separation chamber with a triboelectric charging system which consists of air compressor 1, vibrating feeder 2, airflow regulator 4, and coiled pipeline 5. The ground cannabis material with particle size in the range from 20 to 300 microns is manually or automatically supplied to vibrating feeder 2 and then pneumatically introduced by airflow to the coiled pipeline 5. The powder supply is controlled by airflow regulator 4, which may be manually controlled or actuated through an electronic signal.\u003c/p\u003e\n\u003cp\u003eTriboelectric charging of particles occurs in the coiled pipeline (\u003cspan class=\"CitationRef\"\u003e5\u003c/span\u003e). Due to the different chemical composition, plant biomass particles acquire a positive charge, while trichomes acquire a negative charge. Immediately after triboelectric charging in the pipeline, charged particles are injected into the separation cabinet through a diffuser (\u003cspan class=\"CitationRef\"\u003e6\u003c/span\u003e) with a narrow (about 3 mm) opening. Further separation of trichomes from the plant material is based on the difference in their electrostatic charge. Particles fall in the strong electric field between two electroconductive plate electrodes (\u003cspan class=\"CitationRef\"\u003e10\u003c/span\u003e). The electrodes are oppositely charged from a high-voltage power supply 7, controlled through the control unit 8. The high-voltage source provides an electric field inversely proportional to the distance between electrodes. Both electrodes 10 are insulated using dielectric material 11 to prevent an electrical arc to the grounded metal frame of the separation chamber. Both electrodes are secured to the top of the frame. Non-parallel orientation of electrodes is necessary to create a higher gradient of electric field at the inlet, decreasing downstream the pathway of charged particles.\u003c/p\u003e\n\u003cp\u003eA higher electric field at the inlet applies additional force on the charged particles, resulting in distortion of their trajectory from a vertical free-falling path. Downstream the electric field is decreasing, which results in the attraction of negatively charged particles to the positively charged electrode, while positively charged plant material is attracted to the negatively charged electrode. Uncharged or lost charge plant material falls into collection bins 9.\u003c/p\u003e\n\u003cp\u003eThe innovation is based on the ability of an electrostatic separator to isolate the trichomes from plant biomass based on their unique electrochemical properties. It should be noted that electrostatic separation is not sensitive to the initial concentration of trichomes in plant material and could work with different grades of plant biomass. The spiral configuration of the feeding pipeline allows distributed and uniform exposure of the entire volume of the plant mixture to triboelectric charging. The turbulent regime of dry air prevents the clogging of charged particles. The ability of particles to acquire the charge can be regulated by the degree of throttling of a vibrating dispenser.\u003c/p\u003e\n\u003cp\u003eThe diffusor with a narrow lateral nozzle provides better diffusion of particles in air volume between electrodes, which increases their exposure to the electric field during settling in the gravitational field. Long vertical electrodes provide sufficient exposure of particles to the electric field and therefore, a better separation effect. The trichomes are collected directly from the surface of the charged electrode. However, the manual collecting of trichomes limits the throughput capacity of the electrostatic separator. This deficiency could be eliminated by introducing self-cleanable electroconductive electrodes.\u003c/p\u003e\n\u003cp\u003eSelf-cleanable electrodes contain a moving electroconductive belt, a rotating part, a mechanical drive (motor), and a transmission. The speed of the belt is determined by the accumulation rate of charged particles on the belt surface and controlled by the motor. This design of electrodes will allow full automation of the separation and collection of trichomes.\u003c/p\u003e"},{"header":"5. Experimental validation","content":"\u003cp\u003eCannabis plants Morccan Ba\u0026ntilde;o collected from the field were dried to a moisture content of 0.06\u0026ndash;0.15 g/g dry matter. Dried flowers were separated from stems, stalks, and branches using manual or mechanical methods. Dry plant biomass containing glandular trichomes was sifted using a rotary vibrating sieve or similar device with an upper 250-micron stainless steel mesh and a lower 74-micron mesh screen. The result is a powder colloquially known as kief or hash. It contains glandular and other types of trichomes, pistils, trichome stalks, pollen, dirt, and fine particles of plant material with particle size distribution from 10 to 300 microns. The dry powder was further sifted on a 250 and 74-micron screen. Initial mechanical treatment on the sieve resulted in the detachment and liberation of most of the glandular trichome heads from the attached stalk, which is critical for further electrostatic separation, mostly determining yield and product purity.\u003c/p\u003e \u003cp\u003eOnce the trichomes were liberated, they were processed in the electrostatic separator. The powder is fed into the device, controlling for optimal performance, air flow rate, position and angle of electrodes, temperature, humidity, and powder feed rate. Two fractions are created\u0026mdash;a \u003cem\u003eheads\u003c/em\u003e fraction containing mainly glandular trichome heads and a \u003cem\u003etails\u003c/em\u003e fraction containing mainly undesired contaminants. Powder that did not manage to separate is immediately reprocessed until all powder is separated.\u003c/p\u003e \u003cp\u003eFractions were checked under a microscope to evaluate purity and to determine the nature of the purity or contaminants. If feasible, heads and/or tails are returned to the vibrating screen for further liberation. Fractions were periodically examined under a microscope to determine if liberation was complete. This process can be repeated as necessary to achieve the desired purity. The final product is ready for post-processing or sold as a final product.\u003c/p\u003e \u003cp\u003eThe comparison with conventional methods showed a first-pass average purity of 40\u0026ndash;50%, and 50\u0026ndash;60% if using a Resinator. In contrast, the electrostatic separation with Plasmastatic achieved a first-pass purity of 80\u0026ndash;95% round trichomes with 98% achievable in 2 or more passes.\u003c/p\u003e"},{"header":"6. Advantages of Electrostatic Separation","content":"\u003cp\u003eCompared to conventional wet and dry fractionation, electrostatic separation of cannabis trichomes offers multiple advantages.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eHigh Purity\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eEnables the selective isolation of trichomes with minimal contamination from plant material. Moreover, purity could be improved by fine-tuning electrostatic and aerodynamic fields. Another option is multiple recirculation of the material. In the first run, the trichome fraction could be partially (up to 5%) contaminated with the plant biomass. This material with a purity of 90\u0026ndash;95% could be used for medicinal and cosmetic purposes. For special purposes, an electrostatic separator allows further purification to 99.8% due to multiple cycles or multiple separation stages.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eNon-Destructive\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eDue to the minimal mechanical action, it preserves the integrity of trichomes. Short processing time preserves the quality of bioactive compounds. Oxidation of plant material could be further reduced by electrostatic separation in an oxygen-free environment (for example, helium or nitrogen).\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eSolvent-Free\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eEliminates the need for chemical solvents, reducing environmental impact and production costs. Also, solvent-free technology minimized the damage of trichomes and the escape of water-soluble bioactive compounds.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eScalability\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eSuitable for both small-scale and industrial applications. The separation rate of Plasmastatic is 2 kg/hour; but can be scaled to 100 kg/hour or more. It could be achieved due to increased surface of the electrode system, adjustment of particle flow rate, or a parallel/series combination of basic electrostatic units. The number of electrostatic separation units connected in parallel can achieve the desired throughput separation capacity. With the series configuration of basic electrostatic separation units, the higher purity of the product could be achieved. Due to extremely low energy consumption, electrostatic separators could be integrated with renewable energy sources, such as solar or wind energy in remote locations or mobile applications.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eEnergy Efficiency\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eIt is a non-thermal technology, requiring much less energy compared to traditional methods like solvent extraction. The total energy used for the pilot-scale electrostatic separation is about 20W for the separation throughput of about 100 grams per minute. The energy efficiency of electrostatic separators is increasing with the increase of processing capacity tons per hour.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eChallenges and Limitations\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eDespite high upfront investment for equipment and system setup, electrostatic separator requires minimal maintenance costs. However, the operation requires trained operators to manage the process and troubleshoot issues. The initial preparation stage requires precise drying, grinding and liberation of trichomes from the cannabis material. Also, the electrostatic separator must meet regulatory compliance for safety and quality standards in the cannabis industry, which could differ in different countries. International patents protect the proprietary design of electrostatic separators. The good news is that the first models of electrostatic separators of cannabis trichomes have been on the market since 2023 under the brand \u0026ldquo;Plasmastatic\u0026rdquo; and are commercially available from SC Filtration (www.sambocreeck.com).\u003c/p\u003e"},{"header":"Conclusions","content":" \u003cp\u003eElectrostatic separation technology has the potential to revolutionize the cannabis extraction industry by providing a cleaner and more efficient method for trichome isolation. By leveraging differences in electrical properties, this technique offers a high-purity, environmentally friendly, and scalable solution for cannabis extraction. As the industry grows, adopting innovative technologies like electrostatic separation will be key to meeting the demand for high-quality cannabis products while minimizing environmental impact. Future research should focus on optimizing system design, improving throughput, and integrating this technology with downstream processing methods. Additionally, advancements in material science and electric field modelling could further enhance separation efficiency and scalability.\u003c/p\u003e"},{"header":"Declarations","content":"\u003cp\u003e\u003cstrong\u003eFunding Declaration\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eNo external funding for this research was obtained.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eAuthor Contribution\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eCharles MacGowan:\u003c/strong\u003e Conceptualization, Project administration, Concept verification, Prototype design, Prototype testing, Writing – review \u0026amp; editing. \u003cstrong\u003eAlex Martynenko:\u003c/strong\u003e Conceptualization, Methodology, Theoretical analysis, Experimental research, Writing - original draft, Writing – review \u0026amp; editing.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eDeclaration of Competing Interest\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eData Availability\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eData will be made available on request.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eEthics, Consent to Participate, and Consent to Publish declarations\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eNot applicable\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eConsent to Participate Declaration\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eNot applicable\u003c/p\u003e"},{"header":"References","content":"\u003col\u003e\u003cli\u003e\u003cspan\u003eDelp RC. (2000). Method and apparatus for extracting plant resins. US Patent 6,158,591, Priority from 1998-02-24.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eWatts JE, Amovick TJ. (2019). Rotary separation apparatus and process. US Patent 10,512,938 B2, Priority from 2017-12-05.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003ePhilips T. (2022). How to use static tech to clean dry sift \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003ehttps://thepressclub.co/blogs/tips-tricks/how-to-use-static-tech-to-clean-dry-sift\u003c/span\u003e\u003cspan address=\"https://thepressclub.co/blogs/tips-tricks/how-to-use-static-tech-to-clean-dry-sift\" targettype=\"URL\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eInculet II. Electrostatic Mineral Separation. 153p ed. 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J Electrostat. 2025;134:104027. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003ehttps://doi.org/10.1016/j.elstat.2024.104027\u003c/span\u003e\u003cspan address=\"10.1016/j.elstat.2024.104027\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e.\u003c/span\u003e\u003c/li\u003e\u003c/ol\u003e"}],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":true,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":false,"hideJournal":false,"highlight":"","institution":"","isAcceptedByJournal":true,"isAuthorSuppliedPdf":false,"isDeskRejected":"","isHiddenFromSearch":false,"isInQc":false,"isInWorkflow":false,"isPdf":false,"isPdfUpToDate":true,"isWithdrawnOrRetracted":false,"journal":{"display":true,"email":"[email protected]","identity":"journal-of-cannabis-research","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"jcan","sideBox":"Learn more about [Journal of Cannabis Research](https://jcannabisresearch.biomedcentral.com/)","snPcode":"42238","submissionUrl":"https://submission.springernature.com/new-submission/42238/3","title":"Journal of Cannabis Research","twitterHandle":"","acdcEnabled":true,"dfaEnabled":true,"editorialSystem":"stoa","reportingPortfolio":"BMC/SO AJ","inReviewEnabled":true,"inReviewRevisionsEnabled":true},"keywords":"Glandular trichomes, dry separation, separability, free-fall, electrostatic, cannabis","lastPublishedDoi":"10.21203/rs.3.rs-6033072/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-6033072/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003cp\u003eEfficiently separating trichomes from plant material is critical for producing high-quality cannabis extracts. Traditional methods, such as mechanical sieving and solvent-based extraction, have problems with purity, yield, and environmental impact. This paper explores the application of electrostatic separation as a novel, sustainable, and efficient method for isolating cannabis trichomes. A new concept for a free-fall electrostatic separator for cannabis trichomes is proposed. The technique and equipment minimize the need for manual labor, allowing the separation of cannabis trichomes to a desirable purity. The separator is scalable from 1 to 100 kg/hour and can be fully automated.\u003c/p\u003e","manuscriptTitle":"Electrostatic Separator of Cannabis Trichomes: An Innovative Approach to Extraction","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2025-03-26 07:17:48","doi":"10.21203/rs.3.rs-6033072/v1","editorialEvents":[{"type":"communityComments","content":0},{"type":"decision","content":"Revision requested","date":"2025-04-07T11:35:51+00:00","index":"","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2025-04-01T11:27:30+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"181819099278737720229625482592648330056","date":"2025-03-31T19:01:26+00:00","index":"hide","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2025-03-28T23:17:40+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"248474255896236216884777990066973039029","date":"2025-03-25T10:13:14+00:00","index":"hide","fulltext":""},{"type":"reviewersInvited","content":"","date":"2025-03-24T23:14:01+00:00","index":"","fulltext":""},{"type":"checksComplete","content":"","date":"2025-03-24T05:56:29+00:00","index":"","fulltext":""},{"type":"submitted","content":"Journal of Cannabis Research","date":"2025-03-23T15:44:18+00:00","index":"","fulltext":""}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"journal-of-cannabis-research","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"jcan","sideBox":"Learn more about [Journal of Cannabis Research](https://jcannabisresearch.biomedcentral.com/)","snPcode":"42238","submissionUrl":"https://submission.springernature.com/new-submission/42238/3","title":"Journal of Cannabis Research","twitterHandle":"","acdcEnabled":true,"dfaEnabled":true,"editorialSystem":"stoa","reportingPortfolio":"BMC/SO AJ","inReviewEnabled":true,"inReviewRevisionsEnabled":true}}],"origin":"","ownerIdentity":"844a8deb-3e9e-4769-9cdc-ca2d2fede2db","owner":[],"postedDate":"March 26th, 2025","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"published-in-journal","subjectAreas":[],"tags":[],"updatedAt":"2025-05-05T16:06:20+00:00","versionOfRecord":{"articleIdentity":"rs-6033072","link":"https://doi.org/10.1186/s42238-025-00281-z","journal":{"identity":"journal-of-cannabis-research","isVorOnly":false,"title":"Journal of Cannabis Research"},"publishedOn":"2025-05-04 15:57:11","publishedOnDateReadable":"May 4th, 2025"},"versionCreatedAt":"2025-03-26 07:17:48","video":"","vorDoi":"10.1186/s42238-025-00281-z","vorDoiUrl":"https://doi.org/10.1186/s42238-025-00281-z","workflowStages":[]},"version":"v1","identity":"rs-6033072","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-6033072","identity":"rs-6033072","version":["v1"]},"buildId":"8U1c8b4HqxoKbykW_rLl7","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}