Chain length effect on drug delivery of chrysin modified mPEG–PCL micelles

Abstract

Four chrysin modified mPEG–PCL block copolymers with different chain lengths of mPEG and PCL blocks were synthesized and self-assembled into micelles to load the anticancer drug doxorubicin (DOX). The effect of block chain length on drug delivery was investigated. The four block copolymers were characterized by ¹H NMR, GPC and DSC. The drug loading contents of all the micelles were higher than 20%, the mPEG2k–PCL5k–CHS micelles showed the highest drug loading content and encapsulation efficiency of 26.8% and 93%, respectively. The micelles were spherical with the size increasing after drug encapsulation, and the mean size of the drug loaded micelles was around 100 nanometers. π–π stacking interactions between the micelles and DOX was invoked. The mPEG2k–PCL5k–CHS micelles exhibited the best profile for sustained-release. The cellular uptake and IC₅₀ revealed that the DOX loaded mPEG2k–PCL5k–CHS micelles showed the best anticancer activity in vitro.