Lipid- and TPGS-Based Core-Shell-Type Nanocapsules Endowed with High Paclitaxel Loading and Enhanced Anticancer Potential.

Abstract

The current study elucidates the improved drug loading of paclitaxel (PTX) in lipid- and D-α-tocopheryl polyethylene glycol succinate (TPGS)-based core-shell-type lipid nanocapsules (PTX-TPGS-LNC) for augmenting the therapeutic efficacy and curbing the toxicity. PTX-TPGS-LNCs were formulated by employing anti-solvent precipitation technique and displayed a particle size of 162.1 ± 4.70nm and % practical drug loading of 15.04 ± 2.44%. Electron microscopy revealed that PTX-TPGS-LNCs have spherical morphology and the inner core was surrounded by a relatively lighter region, i.e., layer of lipids and TPGS. The nature of loaded PTX inside the PTX-TPGS-LNC was also confirmed using DSC and PXRD analysis. The in vitro release study showed biphasic and sustained release pattern of PTX from PTX-TPGS-LNC and it showed ~ threefold higher PTX uptake in MCF-7 cell line in comparison to free PTX. Moreover, it was apparent from the cytotoxicity assay that PTX-TPGS-LNC displayed higher cytotoxicity in MCF-7 cells and revealed ~ 2.92-fold decrease in IC50 value as against free PTX when incubated for 72h. The apoptotic index in case of PTX-TPGS-LNC was ~ twofold higher than free PTX. The pharmacokinetic profile of PTX-TPGS-LNC revealed a ~ 3.18-fold increase in t1/2 and a ~ 2.62-fold higher AUC(0→∞) compared to Intaxel®. Finally, treatment with PTX-TPGS-LNC demonstrated significant lowering in the % tumor burden and serum toxicity markers compared to marketed formulation Intaxel®. Thus, the lipid- and TPGS-based core-shell-type LNC with high PTX loading can advance the existing standards of therapy for overshadowing cancer.