# Development of Antimicrobial Comb-like Hydrogel Based on PEG and HEMA by Gamma Radiation for Biomedical Use

## TL;DR

Researchers created a new comb-like hydrogel using PEG and HEMA with gamma radiation, which shows promise for biomedical uses like wound dressings due to its drug delivery and antimicrobial properties.

## Contribution

A novel comb-like hydrogel based on PEG and HEMA was developed using gamma radiation, offering improved drug loading and antimicrobial activity.

## Key findings

- The comb-like hydrogel showed higher ciprofloxacin loading (2 mg g−1) compared to the base net-PEG (1.5 mg g−1).
- Hydrogels with 30 and 66% grafting released only 38 and 48% of the drug after 24 hours.
- The hydrogels inhibited Gram-negative bacteria (E. coli) and showed over 95% cell viability with mouse embryonic fibroblasts.

## Abstract

Poly(ethylene glycol) (PEG) and poly(2-hydroxy ethyl methacrylate) are polymers used for many biomedical applications due to their biocompatibility, non-toxicity, and antibiofouling properties. In this work, a new comb-like hydrogel based on 2-hydroxyethyl methacrylate (HEMA) grafted onto a polyethylene glycol network (net-PEG) was synthesized by gamma radiation from Co60 in two steps. First, PEG (Mw = 20,000) was crosslinked at 30 kGy, and then HEMA was grafted, varying the concentration (5–20% v/v) and irradiation dose (2.5–15 kGy). Results of infrared spectroscopy (FTIR) and thermogravimetric analysis (TGA) confirmed the incorporation of HEMA onto net-PEG. Moreover, the properties of comb-like hydrogel (net-PEG)-g-HEMA were studied through swelling kinetics, drug loading and release, antimicrobial activity, and biocompatibility assays. The findings showed a different behavior in swelling kinetics and drug delivery depending on HEMA grafting. Comb-like hydrogel with 30 and 66% grafting could load more ciprofloxacin (2 mg g−1) than net-PEG (1.5 mg g−1) but only release 38 and 48% at 24 h, respectively. In addition, all drug-loaded hydrogels displayed inhibition for Gram-negative bacteria (E. coli) and a cell viability superior of 95% using mouse embryonic fibroblasts (BALT/T3). Comb-like hydrogel has potential application in the biomedical field such as in wound dressings or controlled drug delivery systems.