In vitro and in vivo anticancer efficacy potential of Quercetin loaded polymeric nanoparticles.

Quercetin (QCT) is a flavonoid, abundantly present in plants and has gained considerable interest for its antioxidant property and chemo preventive activity. Bioavailability of QCT is very low due to its poor aqueous solubility and instability. Researchers are working on the application of nanotechnology to target chemotherapeutic drugs to the tumour site. The aim of the present study was to develop quercetin loaded chitosan nanoparticles (QCT-CS NPs) with enhanced encapsulation efficiency and sustained release property. We prepared biocompatible NPs with small size (<200 nm) and encapsulation efficiency of 79.78%. In vitro drug release study exhibited a cumulative amount of 67.28% release of QCT over a period of 12 h. at pH 7.4. In vitro cytotoxicity assay showed significantly reduced IC50 value of QCT-CS NPs as compared to free QCT (p < 0.05). Intra venous treatment of QCT-CS NPs in tumour xenograft mice with A549 and MDA MB 468 cells exerted significant reduction of tumour volume in comparison to disease control groups (p < 0.05). Serum anti oxidant enzyme superoxide dismutase (SOD) level markedly increased in QCT-CS NPs treated tumour bearing mice than free QCT treated group. In summary, the recent investigations reported successful encapsulation of QCT in chitosan (CS) NPs to target the tumour microenvironment and exhibited enhanced efficacy of QCT-CS NPs in cancer therapy.