ABSTRACT
Poly L(+) lactic acid (PLLA) has become crucial in the biomedical industry for various uses. The direct polycondensation method was used to prepare Poly L(+) Lactic Acid (PLLA). Different catalysts, including metal oxides and metal halides, were used to test the polymerization technique. The effect of the amount of catalysts and the type of coupling agent were investigated. The effect of reaction time and polymerization solvents was also studied. PLLA was loaded with isosorbide dinitrate utilizing the solvent evaporation process. The synthesized polymer-drug system was evaluated by different means such as FT-IR, TGA, DSC, XRD, entrapment efficiency (E.E), drug loading (D.L), particle size analysis, and zeta potential determination. Studies on in-vitro release using UV light at 227 nm at various pH levels were conducted, and the kinetics of release and cytotoxicity using the sulforhodamine B (SRB) assay on human skin fibroblast cells were examined.
ABSTRACT
In 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 12h, followed by a gradual release over 3days. The cumulative riboflavin release from these microcapsules formulations at the end of 3days 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%.
