Synthesis of Crosslinked Micelles and Ring-like Colloids via a Cyclic Template with Multivalency

The pendant hydroxyl groups of c-P (HEMA)(50) were first decorated with ferrocene (Fc) by click coupling to afford c-P(HEMA-Fc)(50), which was then used as a core template to direct the supramolecular comple-xation with beta-cyclodextrin(beta-CD) functionalized with both hydrophilic poly (ethylene glycol) (PEG) and lipoic acid (LA) (beta-CD-PEG-LA) via beta-CD/Fc host-guest inclusion complexation. The resulting supramolecular micelle formed by c-P(HEMA-Fc)(5G)/beta-CD-PEG-LA could be cross-linked via dithiothreitol(DTT)-catalyzed intramolecular self-crosslinking of the decorated LA units to serve as a precursor of the ring-like colloids of crosslinked beta-CD-PEG-LA. The advantage of this cyclic polymer over the previously used three-arm star-shaped polymer as a template lies in the multivalent structure of the cyclic polymer with greater stability and steric hindrance, which results in a significantly increased preparation concentration of 1.0 mg/mL for the ring-like colloids.