A New Dual-peak Fluorescent Probe for Water Content Detection Made from Taxus

A New Dual-peak Fluorescent Probe for Water Content Detection Made from Taxus | Research Square window.SnipcartSettings = { analytics: { enabled: false } }; (function() { var accessVector = localStorage.getItem('access_vector') || ''; window.dataLayer = window.dataLayer || []; if (accessVector) { window.dataLayer.push({ user: { profile: { profileInfo: { snid: accessVector } } } }); } })(); (function(w,d,s,l,i){w[l]=w[l]||[];w[l].push({'gtm.start':new Date().getTime(),event:'gtm.js'});var f=d.getElementsByTagName(s)[0],j=d.createElement(s),dl=l!='dataLayer'?'&l='+l:'';j.async=true;j.src='https://www.googletagmanager.com/gtm.js?id='+i+dl;f.parentNode.insertBefore(j,f);})(window,document,'script','dataLayer','GTM-K279D39R'); Browse Preprints In Review Journals COVID-19 Preprints AJE Video Bytes Research Tools Research Promotion AJE Professional Editing AJE Rubriq About Preprint Platform In Review Editorial Policies Our Team Advisory Board Help Center Sign In Submit a Preprint Cite Share Download PDF Research Article A New Dual-peak Fluorescent Probe for Water Content Detection Made from Taxus Gang Wang, Gang Wang, Yaping Li, Haipeng Chen, Shuqin Tang, Yiyang Cheng, and 3 more This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-1462800/v1 This work is licensed under a CC BY 4.0 License Status: Under Review Version 1 posted 7 You are reading this latest preprint version Abstract In this paper, the leaves of Taxus were used as the sole carbon source, and two kinds of carbon dots blue and red, with different properties, were synthesized by hydrothermal method under different conditions. The red carbon dots were quenched in water, and the blue carbon dots had stable fluorescence properties in water environment. The bimodal fluorescence probe formed by mixing, could accurately and stably measure the water content in ethanol, which was the range of 82.5%-100%, is highly correlated with the fluorescence intensity ratio (I 481 /I 678 ) of mixed carbon dots under 390 nm excitation light, with R 2 = 0.995 and the detection limit as low as 0.31%. The experimental materials are environmentally friendly, low in cost, simple to operate, and the water content measured by proportional fluorescence has high accuracy, which is provides a new method for measuring moisture in ethanol. fluorescent probe Taxus water content Figures Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 Figure 7 Figure 8 Figure 9 Introduction As a fluorescent nano luminescent material, carbon dots are highly sensitive and specific [ 1 – 3 ] , which has received extensive attention in recent years. The main synthesis methods of carbon are various, and the main synthesis method is hydrothermal method. [ 4 , 5 ] Solvothermal method [ 6 , 7 ] and microwave-assisted method [ 8 – 11 ] . Carbon has excellent selectivity in detecting trace antibiotics [ 12 – 15 ] , heavy metal ions [ 16 – 19 ] , Pesticides [ 20 – 24 ] , and medical imaging [ 25 – 27 ] . The aspect plays a huge role compared with unimodal fluorescent probe, bimodal fluorescent probe has high resolution, high precision and strong stability [ 28 – 30 ] advantages, etc. Dried leaves of Taxus are used as biological carbon source, and two kinds of carbon dots (481 nm and 678 nm) are synthesized by hydrothermal method respectively. The fluorescence of red carbon dots can be quenched by water. The disadvantages are weak luminescence, large error, weak sensitivity of blue carbon dots to water, but strong luminescence intensity. The dual-ratio fluorescence probe formed by mixing two kinds of carbon dots, It can effectively make up for the shortcomings of low sensitivity of blue carbon dots and weak luminescence of red carbon dots, enhance the stability of fluorescence data, and can be used for the detection of water content in ethanol. Materials And Methods Reagents The leaves of Taxus were collected in the Taxus base of Fanghua Garden Company, which was cooperated by Dujiangyan Campus of Sichuan Agricultural University.Silica gel, petroleum ether, ethyl acetate, ethanol and various metal salts were purchased from Shanghai McKinley Co., Ltd., and all chemical reagents in this work are analytical pure reagents, which can be used directly without further purification. Instruments and characterization Fluorescence spectrophotometer (Hitachi, F-4500, Tokyo, Japan) recorded the fluorescence spectrum and analyzed the optical properties and related activities of the products. The characterization parameters (morphology, size, etc.) of two kinds of carbon dots were detected by high resolution transmission electron microscope (HRTEM) (JEOL 2100 F, Japan). The content and structure of elements were revealed by spectra measured by ESCALAB 250Xi photoelectron spectrometer (Thermo Scientific, USA). The influence of H 2 O content on the fluorescence spectrum of mixed carbon dots in ethanol system 1) Fresh leaves of Taxus were drying in an oven (60℃, 6 hours), then cutt into small pieces for later use, firstly synthesizing red carbon dots, weighing 1 g of dried leaves, put them in a reaction kettle, 20 ml of absolute ethanol added, left for reaction in the oven at 120℃ for 5 hours, after the reaction kettle naturally cooled, absorbed the reaction solution, filtered through polyethersulfone membrane, and obtained filtrate carrried out silica gel column chromatography. The eluent mixed solution of petroleum ether and ethyl acetate with a volume ratio of 1:1, and the obtained chromatographic solution was concentrated by rotary evaporation, and the concentrated solution was transferred to a blank test tube (the blank test tube was weighted in advance), dried in an oven at 65℃ for 24 hours, then the test tube was weighted again, and the quality of red carbon dots was obtained by differential calculation. 2) Synthesizing blue carbon dots, 1g of dried Taxus leaves were weighted and put them in a reaction kettle, 20 ml of deionized water was added, reaction in an oven at 180℃ for 5h, sucking the reaction solution after the reaction kettle was cooled, filtered with polyethersulfone membrane, concentrated the obtained filtrate by rotary evaporation, concentrated solution was transferred to a blank test tube (the blank test tube was weighted in advance). After dried in an oven at 65℃ for 24 hours, the test tube was weighted again, and the quality of red carbon dots was obtained by differential calculation. 3) Mixing the synthesis and fluorescence spectra of carbon dots, red carbon dots was diluted and blue carbon dots with ethanol to 100 mg/ml respectively, and mixed them to form a mixed solution, setting a series of ethanol-water mixed solutions with equal water content gradient (2.5%) in the range of 82.5%-100% water content, 1 ml of red was mixed and blue carbon dots mixed solution and 1ml of ethanol-water mixed solution with a total volume of 2 ml,The fluorescence spectra of 481nm and 678 nm were recorded at the excitation wavelength of 390 nm, and the fluorescence intensity ratio (I 481 /I 678 ) at 481 nm and 678 nm was calculated. At the same time, 1 mM different kinds of metal ion solutions were prepared, 100 µl of metal ion solutions were mixed with 900 µl of absolute ethyl alcohol, and 1 ml of red, blue and carbon dots solutions were added, totaling 2 ml. The fluorescence spectra were recorded at the excitation wavelength of 390 nm and the fluorescence intensity ratio (I 481 /I 678 ) at 481 nm and 678 nm was calculated.By changing the water content in the ethanol-water mixed solution, the mixed carbon point sensing system can finally selectively detect the water content in ethanol. Results Carbon point characterization HTEM analysis of the red and blue carbon dots and their mixed carbon dots (Fig. 1 ) shows that the red carbon dots are clustered, with the size of 37.8 ~ 64.8 nm, the lattice width of 0.32 ~ 0.36 nm, the blue carbon dots are spherical, with the size of 2.7 ~ 4.1 nm and the lattice width of 0.33 ~ 0.45 nm. After the red and blue carbon dots were mixed, the blue carbon dots gathered around the red carbon dots to form a new aggregate, forming a dual-signal fluorescent solution. Optical Properties of Mixed Carbon Points The ethanol solution of mixed carbon dots is pale yellow or yellow under natural light, which indicates that the prepared carbon dots have good solubility in organic solvents. The fluorescence spectra of blue carbon dots, red carbon dots and their mixed carbon dots were studied at room temperature. Separately different excitation conditions study of blue carbon dots with fixed concentration, and the excitation wavelength ranges from 360 nm to 410 nm, as shown in the Fig. 2 .When the excitation wavelength is 360 nm, a blue fluorescence peak was observed at about 450 nm. With the increase of the excitation wavelength, the fluorescence peak moves to the far-infrared wavelength end, and the intensity of the fluorescence peak gradually decreases. The fluorescence spectra of red fluorescent carbon dots with different excitation wavelengths were studied separately. When the excitation wavelength was 360 nm, the red fluorescence peak was observed at about 678 nm.With the increase of excitation light wavelength, the fluorescence intensity gradually increased, and the fluorescence peak did not moved. After the mixing of blue-red carbon dot solution two peaks were formed at 450 nm and 678 nm, which together form a dual emissivity fluorescence system for moisture detection. In order to determine the best mixing ratio of two kinds of carbon dots, 6 kinds of mixed carbon dot solutions were prepared and carried out fluorescence detection. It can be seen from the figure that the blue band fluorescence intensity decreases with the increase of excitation wavelength, while the red band fluorescence intensity increases with the increase of excitation wavelength. Finally, considering comprehensively, it is determined that the excitation wavelength is 390 nm, and the mixing ratio of blue and red carbon dots is 1:1, so as to complete the final construction of the dual-ratio fluorescent probe. Sensitivity of H 2 O The fluorescence quenching effect was observed by adding different water contents into mixed carbon point ethanol solution (Fig. 5 ). The mixed fluorescence spectra showed that with the increase of water content in the sample, the fluorescence intensity at 481 nm remained unchanged, the quenching effect at 678 nm was obvious, and the fluorescence intensity decreased gradually. The ratio of fluorescence intensity (I 481 /I 678 ) increased with the increase of water content. It shows that the fluorescence intensity ratio of mixed carbon dots (I 481 /I 678 ) is highly correlated with water content. The fluorescence intensity ratio I 481 /I 678 and water content (R 2 = 0.995) fit well in the range of 82.5%-100% (Fig. 6 ). The detection limit is obtained by the ratio of triple blank standard deviation to curve slope, and its value is as low as 0.31%. Selectivity of mixed carbon points In order to test the anti-interference performance of the dual-ratio fluorescent probe, in the presence of 8 kinds of metal ions with a concentration of 100 µM, the mixed solution of ethanol and carbon dots was excited at 390 nm, and the fluorescence intensity ratio (I 481 /I 678 ) of the solution with only fluorescent mixed carbon dots was set as F 0 , and the fluorescence intensity ratio (I 481 /I 678 ) of other metal ions was set as followsThe F 0 /F produced by the quenching phenomenon was observed and calculated. These results show that even if there are excessive metal ions coexisting with the solution, these interferences can be ignored. The acute response of H 2 O in ethanol solution to fluorescence quenching also shows that mixed carbon dots can still accurately identify H 2 O in the presence of various metal ions. The analysis of H 2 O with standard addition In order to evaluate the practical application ability of this method, H 2 O was spiked and recovered, and three kinds of water contents of 85%, 90%, 95%, were spiked and recovered respectively, and then the spiked analysis table was made based on its fluorescence analysis. It can be seen from the Table 1 that the average recovery rate of H 2 O added in ethanol is 99.36%-100.96%, and the relative standard deviation is less than 1%, which can be used for quantitative analysis of samples. Table 1 Sample recovery table H 2 O added(ml) H 2 O found(ml) Recovery(%) RSD(%) 0.8470 99.65% 0.85 0.8475 99.71% 0.32% 0.8531 100.36% 0.8984 99.82% 0.9 0.8946 99.40% 0.21% 0.8988 99.86% 0.9494 99.74% 0.95 0.9545 100.96% 0.27% 0.9488 99.36% Conclusions In this study, the branches and leaves of Taxus were used as raw materials, and two kinds of carbon dots with different properties were synthesized by hydrothermal method. After mixing them, based on the quenching effect of H 2 O on the mixed carbon dots, a double emission fluorescence system was prepared, and a new proportional fluorescence determination method of H 2 O was proposed. The developed method has a linear range of 82.5%-100% and a low detection limit of 0.31%. H 2 O in ethanol was determined,The result is satisfactory, which shows that the sensing system has good sensitivity, high selectivity and effective feasibility. Declarations Acknowledgements Authors thank supports from the Key Research and Development Projects of Sichuan Province and Sichuan Liangshan Science and Technology Plan Projects Funding This research work is supported by the Key Research and Development Projects of Sichuan Province (2018NZ0057), Sichuan Liangshan Science and Technology Plan Projects (21ZDFY0152). Author information Affiliations: Sichuan Agricultural University , Chengdu 611130, Sichuan province, China . Contributions: G W(student), YP L, HP C and YY C jointly completed the experimental part and the writing part, SQ T and YH Y were responsible for the charts and review, QM A reviewed the whole paper and finished the revision of the English manuscript. SR P(professor) and G W (professor) were responsible for the whole experiment and the writing of the later paper. All authors read and approved the final manuscript. Corresponding author: Correspondence to Shangrao Pu and Gang Wang. Ethical Approval: Not applicable. Consent for publication ： Not applicable. Availability of data and material ： The datasets generated during and/or analysed during the current study are available from the correspond-ing author on reasonable request. Informed Consent: A statement regarding informed consent is not applicable. Conflict of Interest: All authors, including Gang Wang – Yaping Li – Haipeng Chen – Shuqin Tang – Yiyang Cheng – Yu Yuhong – Qayoom Majeedano Abdul – Shangrao Pu – Gang Wang, declare no conflict of interest. References Xue H, Yu M, He K et al (2020) A novel colorimetric and fluorometric probe for biothiols based on MnO2 NFs-Rhodamine B system[J]. Anal Chim Acta 1127:39–48 Sai L, Wang X, Chang Q et al (2019) Selective determination of acetone by carbon nanodots based on inner filter effect[J]. Spectrochim Acta Part A Mol Biomol Spectrosc 216:290–295 Anju SM, Anjana RK, Vijila NS et al (2020) Tb-doped BSA–gold nanoclusters as a bimodal probe for the selective detection of TNT[J]. 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Cite Share Download PDF Status: Under Review Version 1 posted Editorial decision: Major revision 04 May, 2022 Reviews received at journal 04 May, 2022 Reviewers agreed at journal 27 Apr, 2022 Reviewers invited by journal 26 Apr, 2022 Submission checks completed at journal 21 Mar, 2022 Editor assigned by journal 21 Mar, 2022 First submitted to journal 17 Mar, 2022 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. Our growing team is made up of researchers and industry professionals working together to solve the most critical problems facing scientific publishing. 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-1462800","acceptedTermsAndConditions":true,"allowDirectSubmit":false,"archivedVersions":[],"articleType":"Research Article","associatedPublications":[],"authors":[{"id":92561228,"identity":"e6e4e235-ca67-4f25-8ac2-b55004aff4c3","order_by":0,"name":"Gang 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4","display":"","copyAsset":false,"role":"figure","size":1085898,"visible":true,"origin":"","legend":"\u003cp\u003e\u003cem\u003eFluorescence diagram of red carbon dots\u003c/em\u003e\u003c/p\u003e\u003cp\u003e\u003cbr\u003e\u003c/p\u003e","description":"","filename":"figure4.jpg","url":"https://assets-eu.researchsquare.com/files/rs-1462800/v1/f34b0bdaed022a2ecf47b33c.jpg"},{"id":19585367,"identity":"b89277a7-6e49-4715-9884-97038295e709","added_by":"auto","created_at":"2022-03-24 19:21:58","extension":"jpg","order_by":5,"title":"Figure 5","display":"","copyAsset":false,"role":"figure","size":1161921,"visible":true,"origin":"","legend":"\u003cp\u003e\u003cem\u003eProportional mixed fluorescence diagram\u003c/em\u003e\u003c/p\u003e\u003cp\u003e\u003cbr\u003e\u003c/p\u003e","description":"","filename":"figure5.jpg","url":"https://assets-eu.researchsquare.com/files/rs-1462800/v1/f87af88b11bb9c42a84721dc.jpg"},{"id":19585221,"identity":"20d4d6da-5003-4648-bfef-7ef02c9d74e3","added_by":"auto","created_at":"2022-03-24 19:20:58","extension":"jpg","order_by":6,"title":"Figure 6","display":"","copyAsset":false,"role":"figure","size":880213,"visible":true,"origin":"","legend":"\u003cp\u003e\u003cem\u003eFluorescence diagram of mixed carbon dots\u003c/em\u003e\u003c/p\u003e\u003cp\u003e\u003cbr\u003e\u003c/p\u003e","description":"","filename":"figure6.jpg","url":"https://assets-eu.researchsquare.com/files/rs-1462800/v1/cbe0474bdec728ced80dd152.jpg"},{"id":19585267,"identity":"2c8aefd3-7399-46c1-ae9a-bb3586e9fc32","added_by":"auto","created_at":"2022-03-24 19:21:30","extension":"png","order_by":7,"title":"Figure 7","display":"","copyAsset":false,"role":"figure","size":166133,"visible":true,"origin":"","legend":"\u003cp\u003e\u003cem\u003eWater content quenching fluorescence diagram\u003c/em\u003e\u003c/p\u003e\u003cp\u003e\u003cbr\u003e\u003c/p\u003e","description":"","filename":"7.png","url":"https://assets-eu.researchsquare.com/files/rs-1462800/v1/7b772ff17584fcbfc16e0777.png"},{"id":19585256,"identity":"ecca0921-5c75-461e-901e-2f3d3b87c730","added_by":"auto","created_at":"2022-03-24 19:21:21","extension":"jpg","order_by":8,"title":"Figure 8","display":"","copyAsset":false,"role":"figure","size":499226,"visible":true,"origin":"","legend":"\u003cp\u003e\u003cem\u003eLinear fitting diagram\u003c/em\u003e\u003c/p\u003e\u003cp\u003e\u003cbr\u003e\u003c/p\u003e","description":"","filename":"figure8.jpg","url":"https://assets-eu.researchsquare.com/files/rs-1462800/v1/127d49897ab54dfa25b937e3.jpg"},{"id":19585248,"identity":"4e943fb9-2f4b-40ff-a461-a2193e85f8f2","added_by":"auto","created_at":"2022-03-24 19:21:08","extension":"jpg","order_by":9,"title":"Figure 9","display":"","copyAsset":false,"role":"figure","size":608445,"visible":true,"origin":"","legend":"\u003cp\u003e\u003cem\u003eHeavy metal interference\u003c/em\u003e\u003c/p\u003e\u003cp\u003e\u003cbr\u003e\u003c/p\u003e","description":"","filename":"figure9.jpg","url":"https://assets-eu.researchsquare.com/files/rs-1462800/v1/e9d6d3d783f4049ac1257328.jpg"},{"id":19702871,"identity":"4caf3bf9-ee9d-42b5-a94f-b2cabcb2ebad","added_by":"auto","created_at":"2022-03-28 20:05:51","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":1261202,"visible":true,"origin":"","legend":"","description":"","filename":"manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-1462800/v1/87d2d264-360e-47d6-8be6-e09e8770926d.pdf"}],"financialInterests":"No competing interests reported.","formattedTitle":"\u003cp\u003eA New Dual-peak Fluorescent Probe for Water Content Detection Made from Taxus\u003c/p\u003e","fulltext":[{"header":"Introduction","content":"\u003cp\u003eAs a fluorescent nano luminescent material, carbon dots are highly sensitive and specific \u003csup\u003e[\u003cspan additionalcitationids=\"CR2\" citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e]\u003c/sup\u003e, which has received extensive attention in recent years. The main synthesis methods of carbon are various, and the main synthesis method is hydrothermal method.\u003csup\u003e[\u003cspan citationid=\"CR4\" class=\"CitationRef\"\u003e4\u003c/span\u003e, \u003cspan citationid=\"CR5\" class=\"CitationRef\"\u003e5\u003c/span\u003e]\u003c/sup\u003e Solvothermal method \u003csup\u003e[\u003cspan citationid=\"CR6\" class=\"CitationRef\"\u003e6\u003c/span\u003e, \u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e7\u003c/span\u003e]\u003c/sup\u003e and microwave-assisted method \u003csup\u003e[\u003cspan additionalcitationids=\"CR9 CR10\" citationid=\"CR8\" class=\"CitationRef\"\u003e8\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR11\" class=\"CitationRef\"\u003e11\u003c/span\u003e]\u003c/sup\u003e. Carbon has excellent selectivity in detecting trace antibiotics \u003csup\u003e[\u003cspan additionalcitationids=\"CR13 CR14\" citationid=\"CR12\" class=\"CitationRef\"\u003e12\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR15\" class=\"CitationRef\"\u003e15\u003c/span\u003e]\u003c/sup\u003e, heavy metal ions \u003csup\u003e[\u003cspan additionalcitationids=\"CR17 CR18\" citationid=\"CR16\" class=\"CitationRef\"\u003e16\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR19\" class=\"CitationRef\"\u003e19\u003c/span\u003e]\u003c/sup\u003e, Pesticides \u003csup\u003e[\u003cspan additionalcitationids=\"CR21 CR22 CR23\" citationid=\"CR20\" class=\"CitationRef\"\u003e20\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR24\" class=\"CitationRef\"\u003e24\u003c/span\u003e]\u003c/sup\u003e, and medical imaging \u003csup\u003e[\u003cspan additionalcitationids=\"CR26\" citationid=\"CR25\" class=\"CitationRef\"\u003e25\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR27\" class=\"CitationRef\"\u003e27\u003c/span\u003e]\u003c/sup\u003e. The aspect plays a huge role compared with unimodal fluorescent probe, bimodal fluorescent probe has high resolution, high precision and strong stability \u003csup\u003e[\u003cspan additionalcitationids=\"CR29\" citationid=\"CR28\" class=\"CitationRef\"\u003e28\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR30\" class=\"CitationRef\"\u003e30\u003c/span\u003e]\u003c/sup\u003e advantages, etc. Dried leaves of \u003cem\u003eTaxus\u003c/em\u003e are used as biological carbon source, and two kinds of carbon dots (481 nm and 678 nm) are synthesized by hydrothermal method respectively. The fluorescence of red carbon dots can be quenched by water. The disadvantages are weak luminescence, large error, weak sensitivity of blue carbon dots to water, but strong luminescence intensity. The dual-ratio fluorescence probe formed by mixing two kinds of carbon dots, It can effectively make up for the shortcomings of low sensitivity of blue carbon dots and weak luminescence of red carbon dots, enhance the stability of fluorescence data, and can be used for the detection of water content in ethanol.\u003c/p\u003e \u003cp\u003e \u003c/p\u003e"},{"header":"Materials And Methods","content":"\u003cdiv class=\"Section2\" id=\"Sec3\"\u003e\n \u003ch2\u003eReagents\u003c/h2\u003e\n \u003cp\u003eThe leaves of \u003cem\u003eTaxus\u003c/em\u003e were collected in the \u003cem\u003eTaxus\u003c/em\u003e base of Fanghua Garden Company, which was cooperated by Dujiangyan Campus of Sichuan Agricultural University.Silica gel, petroleum ether, ethyl acetate, ethanol and various metal salts were purchased from Shanghai McKinley Co., Ltd., and all chemical reagents in this work are analytical pure reagents, which can be used directly without further purification.\u003c/p\u003e\n\u003c/div\u003e\n\u003cdiv class=\"Section2\" id=\"Sec4\"\u003e\n \u003ch2\u003eInstruments and characterization\u003c/h2\u003e\n \u003cp\u003eFluorescence spectrophotometer (Hitachi, F-4500, Tokyo, Japan) recorded the fluorescence spectrum and analyzed the optical properties and related activities of the products. The characterization parameters (morphology, size, etc.) of two kinds of carbon dots were detected by high resolution transmission electron microscope (HRTEM) (JEOL 2100 F, Japan). The content and structure of elements were revealed by spectra measured by ESCALAB 250Xi photoelectron spectrometer (Thermo Scientific, USA).\u003c/p\u003e\n \u003ch2\u003e\u003cspan class=\"BoldItalic\" name=\"Emphasis\" type=\"BoldItalic\"\u003eThe influence of H\u003c/span\u003e \u003csub\u003e\u0026nbsp;\u003cspan class=\"BoldItalic\" name=\"Emphasis\" type=\"BoldItalic\"\u003e2\u003c/span\u003e\u0026nbsp;\u003c/sub\u003e \u003cspan class=\"BoldItalic\" name=\"Emphasis\" type=\"BoldItalic\"\u003eO content on the fluorescence spectrum of mixed carbon dots in ethanol system\u003c/span\u003e\u003c/h2\u003e\n \u003cp\u003e1) Fresh leaves of \u003cem\u003eTaxus\u003c/em\u003e were drying in an oven (60℃, 6 hours), then cutt into small pieces for later use, firstly synthesizing red carbon dots, weighing 1 g of dried leaves, put them in a reaction kettle, 20 ml of absolute ethanol added, left for reaction in the oven at 120℃ for 5 hours, after the reaction kettle naturally cooled, absorbed the reaction solution, filtered through polyethersulfone membrane, and obtained filtrate carrried out silica gel column chromatography. The eluent mixed solution of petroleum ether and ethyl acetate with a volume ratio of 1:1, and the obtained chromatographic solution was concentrated by rotary evaporation, and the concentrated solution was transferred to a blank test tube (the blank test tube was weighted in advance), dried in an oven at 65℃ for 24 hours, then the test tube was weighted again, and the quality of red carbon dots was obtained by differential calculation.\u003c/p\u003e\n \u003cp\u003e2) Synthesizing blue carbon dots, 1g of dried \u003cem\u003eTaxus\u003c/em\u003e leaves were weighted and put them in a reaction kettle, 20 ml of deionized water was added, reaction in an oven at 180℃ for 5h, sucking the reaction solution after the reaction kettle was cooled, filtered with polyethersulfone membrane, concentrated the obtained filtrate by rotary evaporation, concentrated solution was transferred to a blank test tube (the blank test tube was weighted in advance). After dried in an oven at 65℃ for 24 hours, the test tube was weighted again, and the quality of red carbon dots was obtained by differential calculation.\u003c/p\u003e\n \u003cp\u003e3) Mixing the synthesis and fluorescence spectra of carbon dots, red carbon dots was diluted and blue carbon dots with ethanol to 100 mg/ml respectively, and mixed them to form a mixed solution, setting a series of ethanol-water mixed solutions with equal water content gradient (2.5%) in the range of 82.5%-100% water content, 1 ml of red was mixed and blue carbon dots mixed solution and 1ml of ethanol-water mixed solution with a total volume of 2 ml,The fluorescence spectra of 481nm and 678 nm were recorded at the excitation wavelength of 390 nm, and the fluorescence intensity ratio (I\u003csub\u003e481\u003c/sub\u003e/I\u003csub\u003e678\u003c/sub\u003e) at 481 nm and 678 nm was calculated. At the same time, 1 mM different kinds of metal ion solutions were prepared, 100 \u0026micro;l of metal ion solutions were mixed with 900 \u0026micro;l of absolute ethyl alcohol, and 1 ml of red, blue and carbon dots solutions were added, totaling 2 ml. The fluorescence spectra were recorded at the excitation wavelength of 390 nm and the fluorescence intensity ratio (I\u003csub\u003e481\u003c/sub\u003e/I\u003csub\u003e678\u003c/sub\u003e) at 481 nm and 678 nm was calculated.By changing the water content in the ethanol-water mixed solution, the mixed carbon point sensing system can finally selectively detect the water content in ethanol.\u003c/p\u003e\n\u003c/div\u003e"},{"header":"Results","content":"\u003cdiv class=\"Section2\" id=\"Sec6\"\u003e\n \u003ch2\u003eCarbon point characterization\u003c/h2\u003e\n \u003cp\u003eHTEM analysis of the red and blue carbon dots and their mixed carbon dots (Fig. \u003cspan class=\"InternalRef\"\u003e1\u003c/span\u003e) shows that the red carbon dots are clustered, with the size of 37.8\u0026thinsp;~\u0026thinsp;64.8 nm, the lattice width of 0.32\u0026thinsp;~\u0026thinsp;0.36 nm, the blue carbon dots are spherical, with the size of 2.7\u0026thinsp;~\u0026thinsp;4.1 nm and the lattice width of 0.33\u0026thinsp;~\u0026thinsp;0.45 nm. After the red and blue carbon dots were mixed, the blue carbon dots gathered around the red carbon dots to form a new aggregate, forming a dual-signal fluorescent solution.\u003c/p\u003e\n\u003c/div\u003e\n\u003cdiv class=\"Section2\" id=\"Sec7\"\u003e\n \u003ch2\u003eOptical Properties of Mixed Carbon Points\u003c/h2\u003e\n \u003cp\u003eThe ethanol solution of mixed carbon dots is pale yellow or yellow under natural light, which indicates that the prepared carbon dots have good solubility in organic solvents. The fluorescence spectra of blue carbon dots, red carbon dots and their mixed carbon dots were studied at room temperature. Separately different excitation conditions study of blue carbon dots with fixed concentration, and the excitation wavelength ranges from 360 nm to 410 nm, as shown in the Fig. \u003cspan class=\"InternalRef\"\u003e2\u003c/span\u003e.When the excitation wavelength is 360 nm, a blue fluorescence peak was observed at about 450 nm. With the increase of the excitation wavelength, the fluorescence peak moves to the far-infrared wavelength end, and the intensity of the fluorescence peak gradually decreases. The fluorescence spectra of red fluorescent carbon dots with different excitation wavelengths were studied separately. When the excitation wavelength was 360 nm, the red fluorescence peak was observed at about 678 nm.With the increase of excitation light wavelength, the fluorescence intensity gradually increased, and the fluorescence peak did not moved. After the mixing of blue-red carbon dot solution two peaks were formed at 450 nm and 678 nm, which together form a dual emissivity fluorescence system for moisture detection. In order to determine the best mixing ratio of two kinds of carbon dots, 6 kinds of mixed carbon dot solutions were prepared and carried out fluorescence detection. It can be seen from the figure that the blue band fluorescence intensity decreases with the increase of excitation wavelength, while the red band fluorescence intensity increases with the increase of excitation wavelength. Finally, considering comprehensively, it is determined that the excitation wavelength is 390 nm, and the mixing ratio of blue and red carbon dots is 1:1, so as to complete the final construction of the dual-ratio fluorescent probe.\u003c/p\u003e\n\u003c/div\u003e\n\u003cdiv class=\"Section2\" id=\"Sec8\"\u003e\n \u003ch2\u003eSensitivity of H\u003csub\u003e2\u003c/sub\u003eO\u003c/h2\u003e\n \u003cp\u003eThe fluorescence quenching effect was observed by adding different water contents into mixed carbon point ethanol solution (Fig. \u003cspan class=\"InternalRef\"\u003e5\u003c/span\u003e). The mixed fluorescence spectra showed that with the increase of water content in the sample, the fluorescence intensity at 481 nm remained unchanged, the quenching effect at 678 nm was obvious, and the fluorescence intensity decreased gradually. The ratio of fluorescence intensity (I\u003csub\u003e481\u003c/sub\u003e/I\u003csub\u003e678\u003c/sub\u003e) increased with the increase of water content. It shows that the fluorescence intensity ratio of mixed carbon dots (I\u003csub\u003e481\u003c/sub\u003e/I\u003csub\u003e678\u003c/sub\u003e) is highly correlated with water content. The fluorescence intensity ratio I\u003csub\u003e481\u003c/sub\u003e/I\u003csub\u003e678\u003c/sub\u003eand water content (R\u003csup\u003e2\u003c/sup\u003e\u0026thinsp;=\u0026thinsp;0.995) fit well in the range of 82.5%-100% (Fig. \u003cspan class=\"InternalRef\"\u003e6\u003c/span\u003e). The detection limit is obtained by the ratio of triple blank standard deviation to curve slope, and its value is as low as 0.31%.\u003c/p\u003e\n\u003c/div\u003e\n\u003cdiv class=\"Section2\" id=\"Sec9\"\u003e\n \u003ch2\u003eSelectivity of mixed carbon points\u003c/h2\u003e\n \u003cp\u003eIn order to test the anti-interference performance of the dual-ratio fluorescent probe, in the presence of 8 kinds of metal ions with a concentration of 100 \u0026micro;M, the mixed solution of ethanol and carbon dots was excited at 390 nm, and the fluorescence intensity ratio (I\u003csub\u003e481\u003c/sub\u003e/I\u003csub\u003e678\u003c/sub\u003e) of the solution with only fluorescent mixed carbon dots was set as F\u003csub\u003e0\u003c/sub\u003e, and the fluorescence intensity ratio (I\u003csub\u003e481\u003c/sub\u003e/I\u003csub\u003e678\u003c/sub\u003e) of other metal ions was set as followsThe F\u003csub\u003e0\u003c/sub\u003e/F produced by the quenching phenomenon was observed and calculated. These results show that even if there are excessive metal ions coexisting with the solution, these interferences can be ignored. The acute response of H\u003csub\u003e2\u003c/sub\u003eO in ethanol solution to fluorescence quenching also shows that mixed carbon dots can still accurately identify H\u003csub\u003e2\u003c/sub\u003eO in the presence of various metal ions.\u003c/p\u003e\n\u003c/div\u003e\n\u003cdiv class=\"Section2\" id=\"Sec10\"\u003e\n \u003ch2\u003eThe analysis of H\u003csub\u003e2\u003c/sub\u003eO with standard addition\u003c/h2\u003e\n \u003cp\u003eIn order to evaluate the practical application ability of this method, H\u003csub\u003e2\u003c/sub\u003eO was spiked and recovered, and three kinds of water contents of 85%, 90%, 95%, were spiked and recovered respectively, and then the spiked analysis table was made based on its fluorescence analysis. It can be seen from the Table \u003cspan class=\"InternalRef\"\u003e1\u003c/span\u003e that the average recovery rate of H\u003csub\u003e2\u003c/sub\u003eO added in ethanol is 99.36%-100.96%, and the relative standard deviation is less than 1%, which can be used for quantitative analysis of samples.\u0026nbsp;\u003c/p\u003e\u0026nbsp;\u003ctable border=\"1\" id=\"Tab1\"\u003e\n \u003ccaption language=\"En\"\u003e\n \u003cdiv class=\"CaptionNumber\"\u003eTable 1\u003c/div\u003e\n \u003cdiv class=\"CaptionContent\"\u003e\n \u003cp\u003eSample recovery table\u003c/p\u003e\n \u003c/div\u003e\n \u003c/caption\u003e\n \u003cthead\u003e\n \u003ctr\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eH\u003csub\u003e2\u003c/sub\u003eO added(ml)\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eH\u003csub\u003e2\u003c/sub\u003eO found(ml)\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eRecovery(%)\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eRSD(%)\u003c/p\u003e\n \u003c/th\u003e\n \u003c/tr\u003e\n \u003c/thead\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\u0026nbsp;\u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.8470\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e99.65%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\u0026nbsp;\u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.85\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.8475\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e99.71%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.32%\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\u0026nbsp;\u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.8531\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e100.36%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\u0026nbsp;\u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\u0026nbsp;\u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.8984\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e99.82%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\u0026nbsp;\u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.9\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.8946\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e99.40%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.21%\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\u0026nbsp;\u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.8988\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e99.86%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\u0026nbsp;\u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\u0026nbsp;\u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.9494\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e99.74%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\u0026nbsp;\u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.95\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.9545\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e100.96%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.27%\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\u0026nbsp;\u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.9488\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e99.36%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\u0026nbsp;\u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n \u003c/table\u003e\n \u003cp\u003e\u003c/p\u003e\n \u003cp\u003e\u003cbr\u003e\u003c/p\u003e\n\u003c/div\u003e"},{"header":"Conclusions","content":"\u003cp\u003eIn this study, the branches and leaves of \u003cem\u003eTaxus\u003c/em\u003e were used as raw materials, and two kinds of carbon dots with different properties were synthesized by hydrothermal method. After mixing them, based on the quenching effect of H\u003csub\u003e2\u003c/sub\u003eO on the mixed carbon dots, a double emission fluorescence system was prepared, and a new proportional fluorescence determination method of H\u003csub\u003e2\u003c/sub\u003eO was proposed. The developed method has a linear range of 82.5%-100% and a low detection limit of 0.31%. H\u003csub\u003e2\u003c/sub\u003eO in ethanol was determined,The result is satisfactory, which shows that the sensing system has good sensitivity, high selectivity and effective feasibility.\u003c/p\u003e"},{"header":"Declarations","content":"\u003cp\u003e\u003cstrong\u003eAcknowledgements\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eAuthors thank supports from the Key Research and Development Projects of Sichuan Province and Sichuan Liangshan Science and Technology Plan Projects\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eFunding\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThis research work is supported by the Key Research and Development Projects of Sichuan Province (2018NZ0057), Sichuan Liangshan Science and Technology Plan Projects (21ZDFY0152).\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eAuthor information\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eAffiliations:\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eSichuan Agricultural University\u003c/strong\u003e, Chengdu 611130, Sichuan province, China .\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eContributions:\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eG W(student), YP L, HP C and YY C jointly completed the experimental part and the writing part, SQ T and YH Y were responsible for the charts and review, QM A reviewed the whole paper and finished the revision of the English manuscript. SR P(professor) and G W (professor) were responsible for the whole experiment and the writing of the later paper. All\u0026nbsp;authors\u0026nbsp;read\u0026nbsp;and\u0026nbsp;approved\u0026nbsp;the\u0026nbsp;final\u0026nbsp;manuscript.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eCorresponding author:\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eCorrespondence to Shangrao Pu and Gang Wang.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eEthical Approval:\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eNot applicable.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eConsent for publication\u003c/strong\u003e\u003cstrong\u003e：\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eNot applicable.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eAvailability of data and material\u003c/strong\u003e\u003cstrong\u003e：\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe\u0026nbsp;datasets\u0026nbsp;generated\u0026nbsp;during\u0026nbsp;and/or\u0026nbsp;analysed\u0026nbsp;during\u0026nbsp;the\u0026nbsp;current\u0026nbsp;study\u0026nbsp;are\u0026nbsp;available\u0026nbsp;from\u0026nbsp;the\u0026nbsp;correspond-ing\u0026nbsp;author\u0026nbsp;on\u0026nbsp;reasonable\u0026nbsp;request.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eInformed Consent:\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eA statement regarding informed consent is not applicable.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eConflict of Interest:\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eAll authors, including Gang Wang \u0026ndash; Yaping Li \u0026ndash; Haipeng Chen \u0026ndash; Shuqin Tang \u0026ndash; Yiyang Cheng \u0026ndash; Yu Yuhong \u0026ndash; Qayoom Majeedano Abdul \u0026ndash; Shangrao Pu \u0026ndash; Gang Wang, declare no conflict of interest.\u0026nbsp;\u003c/p\u003e"},{"header":"References","content":"\u003col\u003e\u003cli\u003e\u003cspan\u003eXue H, Yu M, He K et al (2020) A novel colorimetric and fluorometric probe for biothiols based on MnO2 NFs-Rhodamine B system[J]. 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Bioconjug Chem 25(7):1323\u0026ndash;1330\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eTamil Selvan G, Varadaraju C, Tamil Selvan R et al (2018) On/Off Fluorescent Chemosensor for Selective Detection of Divalent Iron and Copper Ions: Molecular Logic Operation and Protein Binding[J]. ACS Omega 3(7):7985\u0026ndash;7992\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-fluorescence","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"jofl","sideBox":"Learn more about [Journal of Fluorescence](https://www.springer.com/journal/10895)","snPcode":"10895","submissionUrl":"https://submission.nature.com/new-submission/10895/3","title":"Journal of Fluorescence","twitterHandle":"","acdcEnabled":true,"dfaEnabled":true,"editorialSystem":"em","reportingPortfolio":"Springer Hybrid","inReviewEnabled":true,"inReviewRevisionsEnabled":false},"keywords":"fluorescent probe,Taxus, water content ","lastPublishedDoi":"10.21203/rs.3.rs-1462800/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-1462800/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003cp\u003eIn this paper, the leaves of \u003cem\u003eTaxus\u003c/em\u003e were used as the sole carbon source, and two kinds of carbon dots blue and red, with different properties, were synthesized by hydrothermal method under different conditions. The red carbon dots were quenched in water, and the blue carbon dots had stable fluorescence properties in water environment. The bimodal fluorescence probe formed by mixing, could accurately and stably measure the water content in ethanol, which was the range of 82.5%-100%, is highly correlated with the fluorescence intensity ratio (I\u003csub\u003e481\u003c/sub\u003e/I\u003csub\u003e678\u003c/sub\u003e) of mixed carbon dots under 390 nm excitation light, with R\u003csup\u003e2\u003c/sup\u003e\u0026thinsp;=\u0026thinsp;0.995 and the detection limit as low as 0.31%. The experimental materials are environmentally friendly, low in cost, simple to operate, and the water content measured by proportional fluorescence has high accuracy, which is provides a new method for measuring moisture in ethanol.\u003c/p\u003e","manuscriptTitle":"A New Dual-peak Fluorescent Probe for Water Content Detection Made from Taxus","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2022-03-24 17:00:33","doi":"10.21203/rs.3.rs-1462800/v1","editorialEvents":[{"type":"communityComments","content":0},{"type":"decision","content":"Major revision","date":"2022-05-04T11:30:58+00:00","index":"","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2022-05-04T04:21:57+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"4128e6ba-ce23-47aa-95f1-165e945d18af","date":"2022-04-27T12:33:32+00:00","index":"hide","fulltext":""},{"type":"reviewersInvited","content":"","date":"2022-04-26T17:24:34+00:00","index":"","fulltext":""},{"type":"checksComplete","content":"","date":"2022-03-22T02:34:44+00:00","index":"","fulltext":""},{"type":"editorAssigned","content":"","date":"2022-03-22T02:34:44+00:00","index":"","fulltext":""},{"type":"submitted","content":"Journal of Fluorescence","date":"2022-03-17T15:51:12+00:00","index":"","fulltext":""}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"journal-of-fluorescence","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"jofl","sideBox":"Learn more about [Journal of Fluorescence](https://www.springer.com/journal/10895)","snPcode":"10895","submissionUrl":"https://submission.nature.com/new-submission/10895/3","title":"Journal of Fluorescence","twitterHandle":"","acdcEnabled":true,"dfaEnabled":true,"editorialSystem":"em","reportingPortfolio":"Springer Hybrid","inReviewEnabled":true,"inReviewRevisionsEnabled":false}}],"origin":"","ownerIdentity":"70ee5b5c-f23a-4862-8988-52fcbba9caa4","owner":[],"postedDate":"March 24th, 2022","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"under-review","subjectAreas":[],"tags":[],"updatedAt":"2022-05-27T11:29:23+00:00","versionOfRecord":[],"versionCreatedAt":"2022-03-24 17:00:33","video":"","vorDoi":"","vorDoiUrl":"","workflowStages":[]},"version":"v1","identity":"rs-1462800","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-1462800","identity":"rs-1462800","version":["v1"]},"buildId":"WrCJVZZCHTDjtuVLN7oU0","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}