In vitro degradation of poly (D, L-lactide-co-glycolide) nanoparticles loaded with linamarin

Linamarin-loaded poly (lactide-co-glycolide) (PLGA) nanoparticles (NPs) were prepared by the double emulsion solvent evaporation technique. The formulated PLGA (50:50) and PLGA (85:15) NPs were spherically shaped, having an average particle size < 190 nm, drug entrapment efficiency (50-52%) and zeta potentials ranging from -25 to -30 mV. Interestingly, all formulated PLGA NPs exhibited a controlled biphasic release profile. Polymer degradation was investigated in the current research to determine the major degradation products and then the polymer biocompatibility as well as safety. The PLGA NPs degradation behaviour was investigated by measuring water uptake, mass loss, change of pH of the degradation medium, morphological changes, and lactic and glycolic acid concentrations. Gravimetrical methods, pH meter, scanning electron microscope and high-performance liquid chromatography were employed, respectively. PLGA (50:50) NPs were found to degrade faster than PLGA (85:15) NPs. With regard to water uptake, mass loss and pH change, the degradation behaviour of PLGA (50:50) NPs was significantly (rho < 0.05) different from that of PLGA (85:15) NPs. A complete degradation of PLGA (50:50) NPs was achieved after 102 days, whereas, only about 60% of PLGA (85:15) NPs were degraded within the same period. Complete degradation and release of the degradation products naturally by the body ensures safety of the delivery carrier.