Production of paclitaxel-loaded PEG-b-PLA micelles using PEG for drug loading and freeze-drying

A new approach named PEG-assist is introduced for the production of drug-loaded polymeric micelles. The method is based on the use of PEG as the non-selective solvent for PEG-b-PLA in the fabrication procedure. Both hydration temperature and PEG molecular weight are shown to have a significant effect on the encapsulation efficiency of PTX in PEG4kDa-b-PLA2kDa micelles. The optimal procedure for fabrication includes the use of PEG1kDa as the solvent at 60 degrees C, cooling the mixture to 40 degrees C, hydration at 40 degrees C, freezing at -80 degrees C and freezedrying at -35 degrees C, 15 Pa. No significant difference (p > 0.05) in PTX encapsulation, average particle size and polydispersity index is observed between the samples before freeze-drying and after reconstitution of the freezedried cake. The prepared PTX formulations are stable at room temperature for at least 8 h. Scaling the batch size to 25x leads to no significant change (p > 0.05) in PTX encapsulation, average particle size and polydispersity index. PEG-assist method is applicable to other drugs such as 17-AAG, and copolymers of varied molecular weights. The use of no organic solvent, simplicity, cost-effectiveness, and efficiency makes PEG-assist a very promising approach for large scale production of drug-loaded polymeric micelles.

Automated summary

A new method named PEG-assist is introduced for the production of drug-loaded polymeric micelles. The method utilizes PEG as a solvent and shows significant improvement in the encapsulation efficiency of drugs in the micelles. It is a promising approach for large scale production due to its simplicity, cost-effectiveness, and efficiency.