Stabilization of poly(ethylene glycol)-poly(ε-caprolactone) star block copolymer micelles via aromatic groups for improved drug delivery properties

Abstract

In comparison with unmodified PEG-(PCL)₈ micelles, PEG-(PCL-BTE)₈ micelles exhibited a 15-fold lower CMC, a 15-fold smaller size and a 50% higher drug loading and encapsulation efficiency thanks to the presence of pendant benzyl groups which provide the possibility for micellar core-crosslinking via supramolecular π-π stacking and additional hydrophobic interactions. Whereas the PEG-(PCL)₈ micelles showed significant aggregation during in vitro cytotoxicity experiments, the PEG-(PCL-BTE)₈ micelles showed no signs of aggregation and were capable of solubilizing high concentrations of curcumin, resulting in a significant decrease in MCF-7 cell viability after 48 h. Their ease of synthesis combined with promising results regarding drug delivery make the PEG-(PCL-BTE)₈ micelles appealing for application in the field of encapsulation.