# Cytotoxicity and Antibacterial Activity of Protonated Diallylammonium Polymers: Influence of End Groups and Molecular Weight

## TL;DR

This study examines how the molecular weight and end groups of protonated diallylammonium polymers affect their toxicity and antibacterial properties.

## Contribution

The study reveals how end groups and molecular weight influence both cytotoxicity and bactericidal activity of diallylammonium polymers.

## Key findings

- Low molecular weight PDAATFA polymers show preserved activity and cytotoxicity even with small MW differences.
- Sulfate end groups enhance bactericidal efficiency with minimal toxicity, while dithiocarbonyl groups increase both efficiency and toxicity.
- Low MW PDAATFA polymers are promising for developing new transdermal antimicrobial drugs.

## Abstract

A series of antimicrobial protonated diallylammonium polymers, poly(diallylammonium trifluoroacetate) (PDAATFA), were synthesized by classical polymerization, using an especially elaborated method for preparation of polymers with low molecular weight (MW), and by RAFT polymerization, with different end groups in a range of MW values of (8–43) × 103 g∙mol−1. Cytotoxicity relative to eukaryotic cells (epithelioid lines A-549 and MA-104) and bactericidal activity of the polymers (relative to Pseudomonas aeruginosa and Staphylococcus aureus) are investigated. The effect of the end groups and MW on toxicity and bactericidal activity is shown. Dependence of the activity and, most of all, cytotoxicity on MW is preserved even at a small difference in MW values in the MW range of (18–40) × 103 g·mol−1. A clear dependence of the studied properties on the nature of the terminal group is revealed. Sulfate -O-S(=O)2-O¯ end group has a noticeable effect on the bactericidal efficiency and smaller influence on toxicity, while dithiocarbonyl end group -S-C(=S)-O-CH2-CH3 has a significant effect on efficiency and especially toxicity, drastically increasing the latter. Overall, based on the results obtained, polymers PDAATFA of low MW are considered promising antimicrobial agents for the creation of new transdermal drugs.