Tyrosine-Triazolinedione Bioconjugation as Site-Selective Protein Modification Starting from RAFT-Derived Polymers.

The electrophilic aromatic substitution (SAr) reaction of triazolinediones (TADs) with the phenol moiety of tyrosine amino acid residues is a potent method for the site-selective formation of polymer-protein conjugates. Herein, using poly(,-dimethylacrylamide) (pDMA) and bovine serum albumin (BSA) as model reagents, the performance of this tyrosine-TAD bioconjugation in aqueous solutions is explored. At first, reversible addition-fragmentation chain transfer (RAFT) polymerization with a functional urazole, a precursor for TAD, chain transfer agent is used for the synthesis of a TAD end-functionalized pDMA.

Macromolecular Coupling in Seconds of Triazolinedione End-Functionalized Polymers Prepared by RAFT Polymerization.

The ultrafast and additive-free triazolinedione-click reaction with electron rich (di)enes is a powerful method for the ultrafast ligation of polymer segments. A versatile method is described for the introduction of clickable TAD end groups in various polymer segments, using reversible addition-fragmentation chain transfer polymerization. These triazolinedione-functionalized prepolymers were subsequently used for macromolecular functionalization with a low molecular weight diene and block copolymer synthesis of different types within seconds, at ambient conditions, through the coupling with diene-functionalized polymers such as poly(ethylene glycol) and poly(isobornyl acrylate).