ABSTRACT
@#In this study, in vitro cytotoxicity of carboxymethyl chitosan-rhein conjugate(CR conjugate)and paclitaxel-loaded carboxymethyl chitosan-rhein polymeric micelles(PTX/CR PMs)was evaluated by MTT method in MCF-7 cells. The results showed that CR conjugate displayed good security; PTX/CR PMs in 24 h showed better antitumor activity than Taxol® . Environment-responsive fluorescent probe P4 was used to determine the cellular uptake of PTX/CR PMs in MCF-7 cells. The results also showed that P4 and PTX co-loaded carboxymethyl chitosan-rhein polymeric micelles ［(P4+PTX)/CR PMs］ could be taken up by MCF-7 cells. There was no difference between(P4+PTX)/CR PMs group and(P4+PTX)/CR PMs with verapamil group, suggesting that CR PMs could protect fluorescent probe and/or drugs in their cores avoiding efflux by P-glycoprotein. These results will contribute to in vivo study of CR conjugate and PTX/CR PMs in the future.
ABSTRACT
@#Paclitaxel(PTX), an effective anti-tumor drugs, is water-insoluble. And Cremophor as a solubilizer in its commercial formulation, Taxol® , often causes side-effects which limit its antitumor effect. We designed and synthesized PEGylated carboxymethyl chitosan-rhein(CRmP)conjugate, and further prepared PTX-loaded CRmP polymeric micelles(PTX/CRmP). CRmP conjugate was characterized by fourier transform infrared spectrum(FT-IR)and nuclear magnetic resonance spectroscopy(1H NMR). The particle size and surface morphology of PTX/CRmP were characterized by dynamic laser particle size analyzer(DLS)and atomic force microscope(AFM), respectively. The cytotoxicity of CRmP conjugate and PTX/CRmP against MCF-7 cells were evaluated by MTT assay. The results showed that CRmP conjugates displayed very low cytotoxicity and that PTX/CRmP exhibited better in vitro anti-tumor activity than Taxol® at the same drug concentration after a long-term administration.