"TPGS surface modified bilosomes as boosting cytotoxic oral delivery systems of curcumin against doxorubicin resistant MCF-7 breast cancer cells".

The goal of this work was to design nude bilosomes (Bil) and D-alpha-tocopheryl polyethylene glycol succinate (TPGS) surface coated bilosomes as an oral delivery platform for improving the antitumor activity and poor oral permeability of Curcumin (CUR). Twelve different formulae were acquired from 3.2 factorial analysis considering different independent variables: bile salt type; Sodium taurocholate (STC) or Sodium cholate (SC) and weight percent; 1% or 5 % W/W, both at 2 levels respectively, while Span 60:Cholesterol ratio at 3 levels (1:1, 5:1, 9:1). Following optimization, the selected optimum formula was picked up based on the favorable minimum particle size (187.2 ± 2.2 nm), maximum zeta potential value (-41.3 ± 2.2 mV) and maximum entrapment efficiency (93.4 ± 5.1%) which was further coated with TPGS. The mean fluorescence intensity (MFI) of CUR permeated from the optimum TPGS-F7 and CUR-Bil (F7) formulae exhibited 6.6 and 3.4 folds increase respectively adopting ex-vivo duodenal permeation assay relative to that of CUR suspension. Moreover, the cellular uptake efficiency via the established Caco-2 cells revealed that the uptake of CUR was 61.9 ± 5.3% and 34.76 ± 0.61% from TPGS-F7 and CUR-Bil (F7) relative to the uptake efficiency of CUR suspension (7.4 ± 2.12%). Coherently, TPGS-CUR-Bil showed excellent response expressed in dominant reduction in IC50 value (2.8 ± 0.07 µg/ml) against multidrug resistant (MDR) tumors following 48 h incubation of Doxorubicin Resistant Breast Cancer (MCF-7/ADR) cell lines.