earticle

영어

Nanoparticles or polymeric micelles based on stimuli-responsive drug release have been extensively investigated in recent decades [1,2]. Especially, pH-sensitive drug targeting using pH-sensitive polymers against solid tumor has attracted remarkably since solid tumor has acidic environment [3]. Tumor targeting based on pH-responsive polymeric nanoparticles or micelles is known to have superior antitumor activity against various solid tumors. In this study, we prepared block copolymers composed of poly(L-histidine) (PHS) and dextran (DexPHS) to make pH-responsive polymeric micelles for pH-based tumor targeting. Doxorubicin (DOX) incorporated pH-resposive polymeric micelles of DexPHS block copolymer was prepared by dialysis method. DOX- incorporated polymeric micelles showed that particle size was changed by changes of solution pH, i.e. size of polymeric micelles were increased at acidic pH while they showed reduced particle size at basic pH. Furthermore, drug release was faster at acidic pH than basic pH. These results indicated that DexPHS polymeric micelles have pH-sensitive properties and then drug release was also controlled by pH. Antitumor activity of DOX-incorporated DexPHS polymeric micelles were studied using HCT116 human colon cancer cells. Results indicated that cell viability with polymeric micelle treatment was decreased at acidic pH while DOX treatment did not show significant changes against pH variation. In colculsion, our results indicated that DexPHS polymeric micelles are promising candidates for antitumor drug targeting.