Fluorescent protein-reactive polymers via one-pot combination of the Ugi reaction and RAFT polymerization

By the one-pot combination of the four-component Ugi reaction and RAFT polymerization, multifunctional chain transfer agents (CTAs) containing both protein-reactive groups and trithiolcarbonate could be generated in situ while taking part in the RAFT process. As a result, well-defined polymers containing both fluorescent and protein reactive groups at the chain end were facilely synthesized. Those polymers were successfully used in protein conjugation to create multifunctional protein conjugates by introducing both a synthetic polymer and fluorescent group on the protein surface. Biotin can also be directly used in this system to get a fluorescent biotin polymer for conjugation with avidin, suggesting that this one-pot system may become a general way to prepare different multifunctional polymers for protein modification.