Side-Chain Amino Acid Derived Chiral Macromolecular Architectures: Synthesis and Solution Properties

Barui, Kamal (2016) Side-Chain Amino Acid Derived Chiral Macromolecular Architectures: Synthesis and Solution Properties. PhD thesis, Indian Institute of Science Education and Research Kolkata.

PDF (Ph. D. thesis of Kamal Bauri) Bauri-Kamal__10RS005-_Thesis.pdf - Submitted Version Restricted to Repository staff only Download (5MB)

Abstract

By programming the amino acid sequence it is possible to make plethora of peptides and proteins with diverse structures, properties and functions. Inspired from the nature, for last few decades scientists have been developing different strategies to incorporate amino acids into synthetic polymers either in the main chain or in the side-chain or at the chain-ends, because incorporated amino acids in polymeric system may offer several advantages like different chemical functionalities (amino, carboxyl, hydroxyl and thiol). These functional groups not only improved aqueous solubility and possible interactions with proteins and genes but also facilitates further functionalization with biological molecules. Again, there is a possibility of higher order hierarchical structure formation through inter- and intra-chain association via non-covalent forces such as hydrogen bonding, hydrophobic and electrostatic interactions. The use of naturally occurring amino acids in these hybrid materials increases the biocompatibility of such systems and allows interactions with biological systems. That is why synthetic polymers derived from natural amino acids are very much useful as in drug/gene delivery, tissue engineering, biocompatible materials, etc. On the other hand, in nature there are some renewable resource derived polymers which are cationic in character, such as chitosan, gelatin and dextran. These are appealing candidates for therapeutic applications because of their non-toxicity, biocompatibility, biodegradability and low immunogenicity. As a part of our research, we are also making natural amino acid derived cationic polymers which may find applications in various fields. Synthesis of side-chain amino acids or peptide bearing (meth)acrylate based monomers and their polymers have been reported by controlled living radical polymerization in the long past. In 2010, Sun and Gao reported synthesis of a library of multiamino vinyl poly(amino acids) by ATRP. Those polymers are low cytotoxic and have strong binding ability with DNA. However, even if advanced ATRP techniques have been developed, which allow the reduction of the copper content to a few ppms, copper salts are considered to be cytotoxic. Hence we adapted RAFT polymerization methods to introduce amino acids into synthetic polymers. Herein, we introduced amino acids into the side-chain of acrylate/methacrylate backbone. pH- responsiveness of different side-chain amino acid derived various macromolecular architecture have been studied. Chiroptical characterization and secondary structural conformation formed from those amino acid based polymers were also investigated in detail.

Actions (login required)

View Item