ABSTRACT
Conventional grafting-to approaches to DNA-polymer conjugates are often limited by low reaction yields due to the sterically hindered coupling of a presynthesized polymer to DNA. The grafting-from strategy, in contrast, allows one to directly graft polymers from an initiator that is covalently attached to DNA. Herein, we report blue-light-mediated reversible addition-fragmentation chain-transfer (Photo-RAFT) polymerization from two different RAFT agent-terminated DNA sequences using Eosin Y as the photocatalyst in combination with ascorbic acid. Three monomer families (methacrylates, acrylates and acrylamides) were successfully polymerized from DNA employing Photo-RAFT polymerization. We demonstrate that the length of the grown polymer chain can be varied by altering the monomer to DNA-initiator ratio, while the self-assembly features of the DNA strands were maintained. In summary, we describe a convenient, light-mediated approach toward DNA-polymer conjugates via the grafting-from approach.
Subject(s)
DNA/chemistry , Methacrylates/chemistry , Polymerization , Ascorbic Acid/chemistry , Catalysis , Eosine Yellowish-(YS)/chemistry , LightABSTRACT
We introduce the fully reversible folding of single chain nanoparticles (SCNPs) based on covalent hetero Diels-Alder (HDA) chemistry. A cyclopentadiene (Cp)-protected cyanodithioester (CDTE) monomer is designed and copolymerized with methyl methacrylate (MMA) via RAFT polymerization. The polymer chains are folded and subsequently unfolded by exploiting the reversible nature of the HDA reaction.
