Formulation of Chitosan-Coated Piperine NLCs: Optimization, In Vitro Characterization, and In Vivo Preclinical Assessment

In the present research work, surface-modified nanostructured lipid carriers (NLCs) with chitosan (CH) were prepared to improve the therapeutic efficacy of piperine (PP). NLCs were developed and optimized (CH-PP-NLCs-opt) by design expert software and the selected NLCs surface was coated with chitosan (0.2% w/v). CH-PP-NLCs-opt have shown a particle size of 149.34 ± 4.54 nm and entrapment efficiency of 80.65 ± 1.23%. The results of the solid-state characterization study exhibited that PP enclosed in lipids and present amorphous form. It might be due to the nanoparticle size of NLCs. The drug release study revealed PP-NLCs-opt and CH-PP-NLCs-opt exhibited significant (P < 0.05) difference in PP release (88.87 ± 5.23% and 76.34 ± 4.54%) as compared to pure PP (19.02 ± 2.87%). CH-PP-NLCs-opt exhibited strong bioadhesion than PP-NLCs-opt which has a positive influence the drug permeation and absorption. CH-PP-NLCs-opt showed higher permeation (1083.34 ± 34.15 μg/ cm2) than pure PP (106.65 ± 15.44 μg/cm2) and PP-NLCs-opt (732.45 ± 28.56 μg/ cm2). The significantly enhanced bioavailability of PP was observed from CH-PP-NLCs-opt (3.76- and 1.21-fold) than PP-dispersion and PP-NLCs-opt. The diabetes was induced in rats by a single intraperitoneal administration of streptozotocin (STZ, 40 mg/kg, citrate buffer pH 4.5), and results revealed that PP-NLCs-opt and CH-PP-NLCs-opt reduce the blood glucose level (28.26% and 36.52% respectively) as compared to PP-dispersion (10.87%). It also helps to maintain the altered biochemical parameters. In conclusion, CH-PP-NLC can be a novel oral nanocarrier for the management of diabetes.