Stereocomplexed micelles based on polylactides with β-cyclodextrin core as anti-cancer drug carriers

Abstract

Biocompatible and biodegradable stereocomplexed micelles (SCMs) based on polylactides (PLAs) with β-cyclodextrin (β-CD) core were designed and used as efficient intracellular drug carriers. The micelles formation, stability and drug release behavior of enantiomeric and stereocomplexed micelles with β-CD core were systematically investigated in comparison to the micelles composed of PLAs with dipentaerythritol (DPE) core. The presence of β-CD core allows for the formation of inclusion complex with a model anticancer drug: doxorubicin (DOX), whereas stereocomplexation between PLLA and PDLA enhanced the stability of obtained micelles. By the utility of different supramolecular interactions, we were able to control the release of DOX from obtained micelles. The release tests of DOX from supramolecular nanocarriers showed that DOX release changes in the order of DPE core micelles >β-CD core micelles >SCMs. The antitumor activities of the enantiomeric and stereocomplexed micelles toward HeLa (cervical cancer) and K562 (chronic myelogenous leukemia) cells were tested in vitro. Our data demonstrated that the SCMs/DOX more effectively inhibited the cell proliferation than similar enantiomeric micelles and for the highest concentration of DOX inside the SCMs. Most importantly, micelles were more efficient than free DOX. In summary, the supramolecular interactions can provide a favourable tool to construct a drug delivery system with controlled drug release and efficient tumor cell suppression which is beneficial for cancer therapy.