Antimicrobial properties of bio-inspired poly(4-vinyl-2-pyridone) and itsN-alkylated cationic derivatives

Abstract

Developing new antimicrobial polymers and designing new antimicrobial materials are important research areas for overcoming bacterial resistance. In the present study a new polymer, poly(4-vinyl-2-pyridone), having bioactive structure analogous to that of naturally occurring heterocyclic compounds, was synthesized from 4-vinylpyridine following a simple protocol. To augment the antibacterial properties of the synthesized polymer, N-alkylation of the heterocyclic pyridone moieties was achieved with ethylene chlorohydrin (2-chloroethanol) to generate choline analogous structure. Also, its N-butylated analogue was synthesized as a reference compound to study structure-activity relationship. Structures of the polymers were confirmed using various characterization techniques. Antimicrobial efficacy of the polymers was determined using the minimum inhibitory concentration method in parallel experiments. The test microorganisms used were a Gram (+) bacterium (Staphylococcus epidermidis), Gram (−) bacteria (Salmonella typhi, Pseudomonas aeruginosa and Escherichia coli) and a fungus (Candida albicans). Both the polymer derivatives are far more effective antimicrobial agents than the pristine polymer. Trends in the antimicrobial efficacy of these polymers correlate with their zeta potential values.

Synthesis of a PEGylated Dopamine Ester with Enhanced Antibacterial and Antifungal Activity

“… 13 Moreover, AMPs can be easily tailored by polymer analogous reactions including metathesis reactions to enhance their efficacy. 14 , 15 …”

“…The latter include antimicrobial polymers (AMPs), which have numerous active groups, high efficacy, diminutive toxicity, broad spectrum applicability, easy introduction, and simple modification of structural and functional properties. , The availability of the large number of active groups creates high local concentration, which in turn improves antimicrobial properties many times . Moreover, AMPs can be easily tailored by polymer analogous reactions including metathesis reactions to enhance their efficacy. , …”

“…13 Moreover, AMPs can be easily tailored by polymer analogous reactions including metathesis reactions to enhance their efficacy. 14,15 Furthermore, modification of the existing drugs by drug− polymer conjugation through various chemical reactions such as acrylation, acetylation, or quaternization reactions depends upon the nature or potency of the active functional groups present on the bioactive polymer. 16 One way forward is functionalization of the existing drugs such as methyl DOPA, 17 promethazine, 18 chlorpromazine, 19 diclofenac, 20 oxyphedrine, 21 dicyclomine, 22 and dopamine hydrochloride 23 as these possess antimicrobial activity in addition to their predesigned pharmacological actions.…”