Ultrasound-Assisted Atomization Delivery System Improves the Uniformity of Nanoparticle Distribution in the Mucus Barrier

This study examined how ultrasonic frequency changes droplet size and affects the delivery of nanoparticles through airway mucus. A simple nebulizer system was tested at 1.7 MHz and 2.5 MHz using fluorescent nanoparticles in a mouse model. At 2.5 MHz, the average droplet size decreased from 4.5 µm to 2.1 µm, which increased total lung deposition by 38% and extended mucus penetration by about 25 µm. Fluorescence imaging showed that the higher frequency produced a more uniform spread and higher drug level in the alveolar region. These findings show that adjusting ultrasonic frequency can improve droplet control and nanoparticle movement in the lungs. This approach offers a useful way to improve inhaled drug delivery and may also support future aerosol treatments for long-term lung diseases.