Potential of the capillary electrophoresis method for PLGA analysis in nano-sized drug formulations

Abstract

This study demonstrated applications of the capillary electrophoresis technique for various tasks related to polymer analysis when developing nano-sized drug formulations based on the copolymer of lactic and glycolic acids (PLGA). The focus of this study was to find the appropriate method for PLGA analysis that would address the numerous tasks related to the development of a PLGA-based nano-sized drug formulation. Capillary zone electrophoresis (CZE) was successfully applied for both assessment of PLGA quality (i.e. determination of the PLGA content, content and composition of the water-soluble fraction and lactide/glycolide molar ratio) and for PLGA quantification in a drug nanoformulation, as well as the monitoring of polymer hydrolytic degradation in biorelevant media. This technique enabled selective quantification of the polymer by its lactate or glycolate peaks with high sensitivity (LOD = 0.04 μg PLGA/ml). The study also addresses methodological aspects of applying capillary zone electrophoresis (CZE) for PLGA analysis. Also, the opportunity to quantify PLGA in a nano-sized drug formulation by the nanoparticle peak area in electropherograms was investigated.