Biodegradable polymeric microcapsules for sustained release of riboflavin.

Abstract I n the current study, a series of polylactic acid and polylactic- co -glycolic acid were prepared in an easy, simple, safe and economically feasible way with yield% greater than 90%. Studying the effect of a catalyst on polymerization process was performed. Riboflavin (RF) was chosen as a model drug and microencapsulated in different (drug: polymer) ratios to modify its performance via o/w emulsion solvent evaporation technique and characterized in terms of the morphology and entrapment efficiency (E.E.) and evaluated via in vitro RF release studies. It has been found that, the release rate consists a burst release at the first 12 h, followed by a gradual release over 3 days. The cumulative riboflavin release from these microcapsules formulations at the end of 3 days was 70% and 80% for PDLA and PDLAGA respectively. The kinetics of release profiles were zero order. The highest (E.E.) of RF obtained among all formulations was 85%.