Biodegradable polymeric nanocarriers for oral delivery of antiretroviral drug: Pharmacokinetic and in vitro permeability studies

Abstract

The current work aimed to formulate Darunavir (DRV) loaded poly (ɛ-caprolactone) nanoparticles (NPs) to address the issue of low bioavailability. NPs were formulated by employing D-α Tocopherol Polyethylene Glycol Succinate 1,000 (TPGS) as stabilizer using the solvent emulsification-evaporation technique. The optimized batch had a mean particle size of 173.74 ± 8.01 nm with polydispersity index 0.218 ± 0.01. Entrapment efficiency, drug loading, zeta potential and yield were found to be 82.32 ± 4.18%, 36.57 ± 1.03%, -21.5 ± 0.212 mV and 88.73 ± 2.15% respectively. Stability studies indicated that the formulation was stable at various stability conditions. Fourier Transform Infrared spectroscopy and Differential scanning calorimetry analysis confirmed the absence of interactions between drug and excipients. Scanning electron microscopy revealed spherical monodisperse particles with smooth surface morphology. In vitro dissolution of DRV NPs showed sustained release up to 72 hours. The everted intestinal sac technique proved P-gp efflux inhibition by TPGS and increased the drug permeation by threefold across different intestine sections. In vivo pharmacokinetics depicted a 3.41-fold improvement (p < 0.05) in AUC0-24h of the DRV NPs compared to the plain drug. NPs can be considered as a successful approach for the delivery of DRV as it has increased the transport of drug across the intestinal barriers and improved the oral bioavailability