Enhancement of Particle Collection Efficiency in Electrohydrodynamic Atomization Process for Pharmaceutical Particle Fabrication

Abstract

In the present work, Electrohydrodynamic Atomization was employed to produce biodegradable polymeric microparticles in a new generation of shuttle glass chamber. The effects of different parameters including solution flow rate, nitrogen flow rate, nozzle, and ring voltage on the particle collection efficiency and residual amount of organic solvent in collected particles were investigated systematically. The Taguchi (a combined experimental and statistical) method was used to obtain the optimal collection conditions for the particle collection efficiency. It was found that the important factors affecting particle collection efficiency were given in the following order—solution flow rate, nitrogen flow rate, ring, and nozzle voltage. It was also found that voltage difference between nozzle and ring can significantly affect the particle collection efficiency. Duration of the process, polymer material, and electrical conductivity of the solution were the other factors that affected particle collection efficiency. It was found that solution flow rate and nozzle voltage can considerably affect the size of fabricated particles. Gas Chromatography/Mass Spectrometry was used to determine the residual content of Dichloromethane (DCM) in the collected particles. For all 16 trials, the residual DCM content of the particles fabricated using the EHDA method was well within the limit of safety standards (600 ppm) at the end of process without engaging any additional freeze-drying process. In summary, high collection efficiency and minimum residual solvent in collected particles can be achieved by adjusting the operating parameters and geometrical characteristics of the system.