Degradasi in vitro mikrosfer polipaduan poli(asam laktat) dan poli (kaprolakton)

Abstract

Poly(lactic acid) (PLA) and poly(ε-caprolactone) (PCL) are examples of polymer that can be used as a matrix in drug delivery system because of its degradability property. Drug encapsulation system could be achieved by microspheres formation with emulsion method. The aim of this research was to examine in vitro degradation of microspheres obtained from PLA-PCL polyblend at pH 7.4. Several stages in the study consisted of PLA synthesis, mixing of PLA-PCL in polyblend, microspheres formation, shape and texture observation, and in vitro degradation test. Synthesis PLA produced a polymer with molecular weight 6064 g/mol. Microspheres were formed by emulsification with polyvinylalcohol (PVA) 1.5% (v/v) as an emulsifier. Physical texture of the microspheres was observed with stereomicroscope and scanning electron microscope (SEM). Degradation was analyzed weekly by measuring its molecular weight and viscosity using a digital viscometer, while its weight loss was measured using an analytical balance. The results showed that the composition of PLA microspheres: PCL (9:1) had degradation time faster than the others and it also affected morphological structure, viscosity, and weight of microsphere during degradation analysis. The higher the PLA composition the lower the viscosity value, therefore, the lower the molecular weight of microspheres. During degradation time, viscosity value and weight loss percentage decreased gradually. Kinetics of microsphere weight loss followed between zero and first order kinetic model.