Preparation of Lipid–Polymer Conjugates by Photoiniferter Polymerization and Application to Cell Surface Modification

The growing demand for lipid–polymer conjugates (LPCs) in biomedicine highlights the need for efficient synthesis methods. This study presents a novel Y-type photoiniferter reagent (Lipid-PIT) with a diethyldithiocarbamate group and a diacylglycerol group. Lipid-PIT efficiently initiated the polymerization of vinyl monomers such as oligo(ethylene glycol) methacrylate (OEGMA), N,N-dimethylacrylamide (DMA), tert-butyl acrylate (tBA), and n-butyl acrylate (nBA) under UV irradiation at room temperature, yielding LPCs. Proton NMR confirmed the presence of diethyldithiocarbamate and diacylglycerol moieties at the chain ends. The polymerization kinetics of DMA showed a linear increase in molecular weight (M_n) with time, with a polydispersity (Đ) below 1.50, demonstrating high controllability. Moreover, Lipid-PIT allows for the creation of block copolymers via secondary chain extension. In vitro assays revealed that LPCs synthesized from OEGMA monomers successfully modified L929 and HeLa cell surfaces and exhibited good biocompatibility. This study offers a rapid, efficient method for LPC synthesis with promising biomedical applications.