Bi-Layer Coating of PAA-Chitosan for Prevention of Bacterial Infection and Corrosion of Magnesium Suture as an Alternate Use of Skin Stapler in Intestinal Anastomosis

Abstract

After surgeries suture-related infections and fast corrosion rate of the biodegradable materials. To address these challenges, this study investigates the application of a bilayer coating composed of polyacrylic acid (PAA) and chitosan on AZ31 magnesium sutures. Magnesium-based materials are gaining attention as biodegradable alternatives to traditional non-biodegradable sutures due to their excellent biocompatibility and mechanical properties. However, their susceptibility to rapid corrosion in physiological environments remains a significant limitation. The proposed bilayer coating aims to enhance the corrosion resistance of AZ31 Mg sutures while providing antibacterial properties to mitigate infection risks. The coating was applied using a layer-by-layer deposition technique, which ensures uniform coverage and strong adhesion of the PAA and chitosan layers. The coated sutures were characterized using Fourier Transform Infrared Spectroscopy (FTIR) and Scanning Electron Microscopy (SEM). FTIR analysis confirmed the successful deposition of both PAA and chitosan, with distinct functional groups indicative of enhanced corrosion resistance. SEM images revealed smooth and defect-free surface morphology, further supporting the effectiveness of the coating process. Antibacterial assays demonstrated the broad-spectrum efficacy of the coated sutures, showing significant zones of inhibition against Escherichia coli (E. coli), a common pathogen associated with surgical site infections. These findings collectively highlight the potential of the PAA–chitosan dual-layer coating to significantly improve the performance of AZ31 Mg sutures. By enhancing corrosion resistance and imparting antimicrobial properties, this innovative approach offers a promising solution for applications such as intestinal anastomosis. The study underscores the importance of developing advanced coatings for biodegradable materials, paving the way for safer and more effective surgical sutures that can reduce post-operative complications and improve patient outcomes.