Synthesis, characterization, and cytotoxicity analyses of ABA-type block copolymer bearing p-xylene-bis(2-mercaptoethyloxy) core

ABA–type amphiphilic novel poly(N-vinyl pyrrolidone)-block-poly(D,L-lactide)-block-poly(N-vinyl pyrrolidone) (PNVP-b-PDLLA-b-PNVP), triblock copolymer was synthesized via combination of ring-opening polymerization (ROP) and reversible addition-fragmentation chain transfer (RAFT) polymerization using novel bifunctional PDLLA based RAFT macro chain transfer agent (CTA) bearing p-xylene-bis(2-mercaptoethyloxy) core. For this goal, bifunctional initiator p-xylene-bis-(1-hydroxy-3-thia-propane) (1) was synthesized by the reaction of α,α'-dibromo-p-xylene with 2-mercaptoethanol in the presence of KOH in ethanol. PDLLA-diol was synthesized by metal-free organocatalyzed ROP of D, L-lactide (D,L-LA) in presence of 4-(dimethylamino) pyridine (DMAP) as catalyst using (1) as initiator Dibromoester end-functionalized PDLLA-based macroinitiator (3) was prepared by esterification of hydroxyl end groups of PDLLA-diol (2). PDLLA macro-CTA (4) was then synthesized via a substitution reaction of (3) with potassium ethylxanthate (KEX). Finally, PNVP-b-PDLLA-b-PNVP triblock copolymer (5) was synthesized RAFT polymerization of NVP using (4). Characterization of the molecular structures for synthesized novel polymers was made by spectroscopic (FTIR, 1H NMR) methods. In this study's application phase, polymers' effectiveness was examined on cervical cancer cells. Cytotoxicity and metastatic effects were evaluated in vitro on HeLa cell lines. In our study, we observed no toxic effect of the block copolymer below 600 µg/mL on the HeLa cervical cancer cell line and in future studies on drug delivery studies of cancer treatments.