Stepwise targeted drug delivery to liver cancer cells for enhanced therapeutic efficacy by galactose-grafted, ultra-pH-sensitive micelles.

Abstract

Chemotherapeutic efficacy is limited by poor tumor selectivity, which also causes severe toxicity in normal tissues and organs, although many targeted drug delivery systems have been developed by passive targeting strategies or active targeting strategies with specific targeting ligands in recent years. Herein, galactose-grafted, ultra-pH-sensitive, ortho ester-based drug carriers, which can respond to both extracellular and intracellular pH, and target to galactose-receptors in cell membrane, have been successfully constructed by facile method, therefore achieving stepwise targeting to microenvironment of liver cancer and then enhancing drug accumulation and tumor inhibition. The strategy of designing dual-stimuli-responsive copolymers can be potentially useful, and extrapolated to synthesizing other categories of highly labile drug carriers in a range of biomedical applications.