A method for the prediction of drug content of poly(lactic-co-glycolic)acid drug carrier nanoparticles obtained by nanoprecipitation

Poly(lactic-co-glycolic acid) drug loaded nanoparticles are applied successfully to increase the distribution and bioavailability of hydrophobic drug molecules, although the generally low drug content implies a limitation. Poly(lactic-co-glycolic acid) nanoparticles were prepared by nanoprecipitation to encapsulate model drugs, a series of alkyl-hydroxy-benzoate (parabens) from methyl-to octyl with increasing hydrophobicity to address the influence of drug property on the encapsulation. The drug content and encapsulation efficiency were found to be substantially different for the various parabens. The analysis of the miscibility of the polymer with parabens using their solubility parameters could not provide satisfactory explanation for the experimental findings.