Novel POSS unimolecular micelles for drug delivery

This study developed unimolecular micelles featuring a polyhedral oligomeric silsesquioxane (POSS) core and eight arms by reacting POSS with the block copolymer mPEG- b -PCL, which were utilized as a drug delivery platform. Compared to conventional self-assembled polymeric micelles, POSS unimolecular micelles exhibit precise dimensions and are monodisperse. They lack a critical micelle concentration (CMC) and can maintain stability in physiological environments with varying concentrations and pH levels. The POSS unimolecular micelles are constructed using biocompatible materials, specifically polycaprolactone and polyethylene glycol. POSS features a rigid cage-like structure along with multifunctional group characteristics, which serve as a stable core for unimolecular micelles. This significantly enhances both the drug-loading capacity and thermodynamic stability of the micelles, rendering them suitable for applications in physiological environments. POSS unimolecular micelles can encapsulate the anticancer drug doxorubicin, offering enhanced stability and prolonged drug release time compared to conventional polymer micelles, thereby providing a sustained-release effect.