Synthesis & characterization of amino acid-based acrylamide derived amphiphilic block copolymer using a new xanthate and its influence on cell cytotoxicity & cell viability

Abstract

The development of amino acid-based polymers was due to their unique properties and structures like of biocompatible polymers having sensitive effects for numerous medicinal and biological actions like biochemical sensing and controlled release of drugs. To achieve this, poly (N-vinylpyrrolidone) (PNVP) and its block copolymer poly (N-vinylpyrrolidone)-b-poly (N-acryloyl-L-phenylalanine) (PNVP-b-PNALP) were synthesized by using a xanthate i.e., ethyl 2-((isopropoxycarbonothioyl)thio)-2-methylpropanoate (IPX), which exhibits good control RAFT polymerization. The plot between molar mass and conversion yields a linear line which confirms the pseudo-first-order kinetics, and molar mass distribution (Ðm) was found between (1.50–1.24). Both polymers were characterized by 1H NMR, FTIR, DSC, TGA-DTA, GPC, and XRD analysis. TEM and DLS study of the aqueous solution of the block copolymer (PNVP-b-PNALP) exhibited self-assembly (119–160 nm with a few smaller particles of 91 nm). Different concentrations of polymers (200–0.75 μM) were evaluated for their toxicities on macrophages (RAW 264.7) and cancer (MCF7) cell lines. The polymers were found to be nontoxic as we did not observe any significant changes in the rate of proliferation of both cells even at higher concentrations (up to 100 μM). However, the polymers were found to induce apoptosis-like changes in the cancer cells up to 100 μM, albeit not significant.