2023 AIChE Annual Meeting
How Many Passes Does It Take? an Investigation to Determine the Optimal Number of Liposome Extrusion Cycles
Liposomes are lipid-based nanoparticles commonly known for their drug carrying capacity and value in membrane and nanoreactor research. One commonly used method of fabricating liposomes of particular size is membrane extrusion in which liposomes are pushed through a porous membrane and break apart to form smaller liposomes. However, the details pertaining to liposome extrusion, such as the number of passes, membrane pore sizes, and pre-extrusion sample preparation, vary between different labs. The specific goal of this project is to establish a relationship between the number of passes through a track-etched, polycarbonate membrane, and the average diameter and diameter distribution of extruded liposomes. To investigate, we extrude samples to several different amounts varying from 1 to 1,000 passes and measure the average hydrodynamic diameter and diameter distribution of each using dynamic light scattering (DLS). In addition to cross-experiment comparison, we compare liposome size data to the size distribution of membrane pores, which is acquired using scanning electron microscopy (SEM) and subsequent image processing. Cases in which liposome and pore size distributions are similar suggest that extrusion has been completed, and further extruding would not change the liposome size. These results provide relevant researchers with the optimal number of passes for liposome extrusion that will allow them to form ideal distributions in the shortest amount of time.