Preparation and Characterization of Pectin/HEMA/ZrO2 Composite Via Gamma Irradiation: Antimicrobial and Anti-Inflammatory Activities

Abstract

This study explores the gamma radiation-assisted synthesis of a novel biodegradable polymeric composite composed of pectin (PC), poly 2-hydroxyethyl methacrylate (HEMA), and polypropylene glycol (PPG) as a cross-linker reinforced with zirconium dioxide (ZrO₂) nanoparticles, PC/PHEMA/ ZrO₂. Gamma radiation induces polymerization and crosslinking while promoting the decomposition of zirconium oxychloride (ZrOCl₂) to form ZrO₂ nanoparticles in situ. The optimized formulation (PC: HEMA: PPG: ZrO₂ = 2:20:2:1 wt%) was obtained at a 10 kGy irradiation dose. The hydrogel exhibited a moderate swelling capacity, with rapid initial water uptake and equilibrium at ∼81. The second-order swelling kinetic model provided a better fit to the experimental data than the first-order kinetic one. X-ray diffraction (XRD) analysis confirmed the hydrogel's amorphous nature, showing no changes upon ZrO₂ incorporation. Scanning electron microscopy (SEM) revealed that the addition of PPG enhanced structural uniformity, while ZrO₂ increased surface roughness, which may improve antimicrobial properties. Biocompatibility tests showed high cell viability (IC₅₀ = 224.16 ± 2.52 µg/mL in oral epithelial cells), indicating its potential for biomedical applications. Antimicrobial evaluation confirmed the composite's effectiveness against pathogenic microorganisms, and anti-inflammatory assays demonstrated significant activity (IC₅₀ = 9.43 µg/mL). PC/PHEMA/ZrO₂ holds promise for biomedical applications due to its biocompatibility, antimicrobial efficiency, and anti-inflammatory properties.