Comparative evaluation of cyclosporine A/HPβCD-incorporated PLGA nanoparticles for development of effective ocular preparations.

To improve poor water solubility of cyclosporine A (CsA), hydroxypropyl-beta-cyclodextrin (HPβCD) was incorporated into the nanoparticle formulation. Solid complexes of CsA with HPβCD in different ratios were prepared by the kneading method. CsA containing alone or in combination with HPβCD in poly-lactide-co-glycolide (P-CsA or P-CsA-HPβCD) nanoparticles were prepared by the emulsification solvent evaporation method. The mean size of CsA-loaded NPs was found to be approximately 220 nm. The solubility of CsA was significantly improved and the phase solubility diagram of CsA-HPβCD systems showed an A(L) type phase. Nanoparticles showed high CsA encapsulation efficiency (88%) and production yield (89%). Release rate was increased by the presence of HPβCD and total cumulative release ranged from 75% to 96% in 24 h. In vitro cytotoxicity study assay resulted in a low toxicity for all types of nanoparticles. After 6 h incubation period, the cellular uptake was found at 33% and 32% for P-CsA and P-HPβCD-CsA nanoparticles, respectively.