The effect of different organic solvents in liposome properties produced in a periodic disturbance mixer: Transcutol®, a potential organic solvent replacement

Abstract

Liposomes are versatile particles used in the biomedical field as drug delivery systems (DDS). Liposome production using micromixers have shown to yield nanoparticles for DDS in a single step with a controllable size by changing flow conditions. Nonetheless, other factors such as the organic solvent, play a crucial role in the liposome formation process. Furthermore, drug solubility and toxicity are pivotal when deciding which organic solvent to choose. In this work, liposomes were produced in a periodic disturbance mixer (PDM). We investigated three conventional organic solvents: ethanol, methanol, and isopropanol as well as Transcutol®. We assessed the organic solvent influence on liposome characteristics (size, size distribution and zeta potential). Among the four organic solvents, Transcutol® yielded the smallest liposomes, which ranged from 80 nm to 160 nm. Moreover, a more in-depth investigation showed that Transcutol® produced smaller or similar-sized particles under different temperature and lipid concentration conditions, compared with ethanol. Furthermore, we proved that particles zeta potential was not influenced by the organic solvent, production temperature, or lipid concentration. This work results show that Transcutol® could replace the conventional alcohol-based solvents and can potentially avoid filtration steps due to its low toxicity. Therefore, the present approach is appealing for DDS development.