Catharanthus roseus leaf extract-synthesized chitosan nanoparticles for controlled in vitro release of chloramphenicol and ketoconazole

We report the size-controlled chitosan nanoparticles synthesized by Catharanthus roseus leaf extract-mediated cross-linking of chitosan. Optimization of pH, ratio of chitosan to leaf filtrate concentration, and cross-linking time was performed for designing factorial synthetic strategy, which revealed minimum diameter (45 nm) of chitosan nanoparticles at pH 3 by employing chitosan/leaf extract in the ratio 3:1. The biogenically synthesized chitosan nanoparticles were further explored for encapsulation and controlled release of ketoconazole and chloramphenicol. The resulting drug-loaded chitosan nanoparticles showed size-dependent drug entrapment efficiency of 82.88 and 78.96 % with drug-loading capacity of 41.44 and 39.48 % for chloramphenicol and ketoconazole, respectively. The cumulative in vitro drug release up to 12 h was achieved which suggests enhanced efficacy of green synthesized chitosan nanoparticles for therapeutic and drug delivery applications. So far, there is no report concerning biogenic synthesis of chitosan nanoparticles; hence, it is being reported for the first time.