(128d) Liposome Production and Concomitant Loading of Drug Simulants By Microfluidic Hydrodynamic Focusing

Liposomes are spherical vesicles enclosed by phospholipid bilayers. Nanoscale liposomes with diameters around 100nm are widely employed for drug delivery in the pharmaceutical industry. Compared to conventional batch production of drug-loaded liposomes, liposome fabrication and concomitant drug loading by microfluidics potentially allows better control of liposome size, requires fewer toxic solvents, allows for more efficient use of drug molecules, and enables tunable loading efficiency. In this research project, nanoscale liposomes were fabricated using the microfluidic hydrodynamic focusing (MHF) approach, and the effects of flow rate ratio (FRR) on liposome size and drug loading efficiency were studied. The widths of microfluidic channels were within 100μm and FRR was varied from 10 to 50. For analysis purposes, fluorescein isothiocyanate was used as a hydrophilic drug simulant and Nile red was used as a hydrophobic drug simulant. The drug simulant concentrations were analyzed by a microplate reader and the liposome size was measured through dynamic light scattering. The experiment results showed that hydrophilic drug simulant loading efficiency increased as FRR increased and eventually plateaued. The hydrophobic drug simulant loading efficiency and FRR had a positive linear correlation. It was also confirmed that liposome size decreased as FRR was increased, and that liposomes were larger when loaded with the hydrophobic drug simulant compared to unloaded liposomes and liposomes loaded with the hydrophilic drug simulant alone. The results presented the effect of FRR on liposome size and drug loading efficiency, and suggested that liposome size and drug loading efficiency are tunable with the MHF technique. This provided evidence to encourage further studies of microfluidic liposome fabrication in the pharmaceutical industry.