Folate-Conjugated Micelles and Their Folate-Receptor-Mediated Endocytosis

A folate‐conjugated copolymer PEG‐PLA‐PLL/folate was synthesized and mixed with pure PEG‐PLA‐PLL and a fluorescent model drug mFITC to prepare folate‐conjugated micelles. The distribution of micelles was studied on cancer‐cell‐bearing mice via frozen slicing. The results show that mFITC is successfully encapsulated into folate(+) and folate(−)micelles; PEG‐PLA‐PLL micelles the latter can be internalized by both HeLa and CHO cells without selectivity due to their cationic surface charges, while folate(+)micelles exhibit more preferential endocytosis by HeLa cells than by CHO cells. The folate(−)micelles showed retention in both organs and tumors. The folate(+)micelles are a promising active targeting drug delivery system for FR over‐expressing cells and they accumulate in tumor beds. Folate‐conjugated micelles for the selective delivery of hydrophobic molecules are developed. They have potential to deliver drugs into folate‐receptor over‐expressing cancer cells HeLa via folate receptors mediated endocytosis in vitro and in vivo. These micelle systems can be used in the delivery of anticancer drugs and their selective target to cancer cells.