Objectives: A system of stearic acid (SA)-modified Bletilla striata polysaccharide (BSP) micelles was developed for the targeted delivery of docetaxel (DTX) as a model anticancer drug (DTX-SA-BSP).
Methods: Particle size, zeta potential and DTX release in vitro were measured in release media at different pH values. Quantitative cellular uptake, cytotoxicity assay in vitro and antitumour efficacy in vivo were also evaluated. Cell apoptosis was assessed by flow cytometry.
Key findings: DTX-SA-BSP copolymer micelles displayed pH-dependent properties in the respects of particle size, zeta potential and in vitro release behaviour ranging from pH 5.0 to pH 7.4. DTX-SA-BSP copolymer micelles showed higher release rate at pH 5.0 than that at pH 6.0 and 7.4. In vitro cytotoxic effect of DTX-SA-BSP copolymer micelles was higher than that of DTX injection. The results of high-performance liquid chromatography determination confirmed that DTX cellular uptake of micelles was enhanced compared with that of DTX injection. Anticancer activity in vivo further confirmed the enhanced tumour targeting and anticancer efficacy of DTX-SA-BSP copolymer micelles.
Conclusions: The above results show that DTX-SA-BSP copolymer micelles have pH sensitivity. SA-BSP copolymers are a promising carrier for delivering hydrophobic anticancer drugs.
Keywords: Bletilla striata polysaccharide; cellular uptake; copolymer micelle; docetaxel; in vivo antitumour effect.
© 2018 Royal Pharmaceutical Society.