# Biodegradable Antibacterial Nanostructured Coatings on Polypropylene Substrates for Reduction in Hospital Infections from High-Touch Surfaces

## TL;DR

This paper introduces biodegradable antibacterial coatings for hospital surfaces to reduce infections by using nanostructured materials with proven antimicrobial effectiveness.

## Contribution

A novel nanostructured coating system combining chitosan, poly(ε-caprolactone), and chlorhexidine-loaded zirconium phosphate nanoparticles is developed and tested for hospital surface decontamination.

## Key findings

- Chitosan- and PCL-based coatings showed strong antibacterial activity against clinical pathogens.
- PCL-based coatings exhibited faster and broader bactericidal effects while maintaining cytocompatibility.
- The coatings are suitable for sustainable and scalable decontamination of high-touch hospital surfaces.

## Abstract

Healthcare-associated infections (HCAIs) remain a significant global challenge, as pathogenic microorganisms can persist on hospital surfaces and medical equipment, contributing to severe infections and epidemic outbreaks. Conventional preventive measures, including disinfection procedures and personal protective equipment, are often insufficient to ensure complete microbial control, prompting interest in innovative antimicrobial surface technologies. This study reports the design, preparation, and comprehensive characterization of chitosan- and poly(ε-caprolactone)-based antibacterial coatings incorporating chlorhexidine-loaded zirconium phosphate (ZrPCHX) nanoparticles. Coatings were deposited by optimized spray and brush techniques to obtain uniform, adherent, and well-defined films. Their morphological, physicochemical, mechanical, and cytocompatibility properties were systematically evaluated, and antibacterial efficacy was assessed against clinically relevant pathogens following ISO 22196:2011 and additional protocols simulating realistic hospital conditions. Both coating systems demonstrated pronounced antibacterial activity, with the PCL-based formulation exhibiting a faster and broader bactericidal effect while maintaining good cytocompatibility. These findings support the potential of the developed nanostructured coatings as sustainable and scalable materials for the active decontamination of high-touch hospital surfaces, offering continuous antimicrobial protection and contributing to a reduction in HCAI incidence.