3D-Printing Enables Fabrication of Swirl Nozzles for Fast Aerosolization of Water-Based Drugs

• Published in: Journal of microelectromechanical systems Vol. 30; no. 2; pp. 181 - 183
• Main Authors: Last, Torben S., Stemme, Goran, Roxhed, Niclas
• Format: Journal Article
• Language: English
• Published: New York IEEE 01.04.2021; The Institute of Electrical and Electronics Engineers, Inc. (IEEE)
• Subjects: Aerosols; Asthma; Bars; Chip formation; Cleanrooms; Cystic fibrosis; drug delivery; Drugs; Formulations; high-pressure microfluidics; Inhalers; Lasers; Medical MEMS; Polymers; portable inhalers; Prototypes; Resins; Spray nozzles; Three dimensional printing; two-photon-polymerization
• ISSN: 1057-7157; 1941-0158; 1941-0158
• DOI: 10.1109/JMEMS.2021.3053644

Portable inhalers are used for delivering drugs to the lung in the form of aerosols and form the standard treatment for diseases such as Asthma, COPD, and cystic fibrosis. However, for aqueous drug formulations, spray nozzle chips have so far been restricted to cleanroom manufacture due to their small feature sizes. Here we present a spring-actuated 3D-printed swirl nozzle that sprays an aqueous drug solution, matching propellant-containing inhalers in aerosolization time. The use of two-photon polymerization enables the small nozzle feature size of 100 <inline-formula> <tex-math notation="LaTeX">\mu \text{m} </tex-math></inline-formula> and device print times of only 4 min, making serial mass-fabrication a viable option. Our 35 bar spring-operated swirl nozzle prototype achieves mean volumetric particle sizes of 12.5<inline-formula> <tex-math notation="LaTeX">{\mu }\text{m} </tex-math></inline-formula> on doses of 100<inline-formula> <tex-math notation="LaTeX">{\mu }\text{l} </tex-math></inline-formula>, aerosolized in 270 ms, as fast as a propellant-driven inhaler. [2021-0002]