Javed Nauman, Hanif Aimen, Butt Muhammad Shoaib
Atta-ur-Rehman School of Applied Biosciences (ASAB), National University of Sciences and Technology (NUST), H-12, Islamabad 44000, Pakistan.
School of Chemical and Material Engineering (SCME), National University of Sciences and Technology (NUST), H-12, Islamabad 44000, Pakistan.
Int J Biol Macromol. 2025 Jun;315(Pt 1):144162. doi: 10.1016/j.ijbiomac.2025.144162. Epub 2025 May 13.
Postoperative complications such as suture-related infections and rapid corrosion of biodegradable materials remain critical challenges in gastrointestinal surgeries. This study investigates a novel dual-layer coating of polyacrylic acid (PAA) and chitosan applied to AZ31 magnesium (Mg) alloy wires. The AZ31 Mg wires were coated through layer-by-layer (LbL) deposition, with polyethylene imine used as a primer to facilitate attachment. The coated sutures were characterized using Fourier Transform Infrared Spectroscopy (FTIR), Scanning Electron Microscopy (SEM), tensile testing, hydrogen evolution, stability studies, electrochemical corrosion, antibacterial assays, hemolysis, MTT assay, and in vivo evaluation. FTIR analysis confirmed the successful deposition of PAA and chitosan, revealing functional groups indicative of anticorrosive and antibacterial activity. The tensile strength of coated wires increased significantly from 252 N to 420 N. Hydrogen evolution was reduced by >80 %. Electrochemical corrosion demonstrated a significant reduction in corrosion current density (Icorr), from 8.805 × 10 A/cm for uncoated samples to 1.807 × 10 A/cm for the PAA-Ch coated samples, with the corrosion potential (Ecorr) shifting from -1.393 V to -2.935 V. Antibacterial assays revealed broad-spectrum efficacy against S. aureus, E. faecalis, E. coli, and K. pneumoniae. Hemolysis percentages remained below 2 %, and the MTT assay indicated excellent cytocompatibility, with cell viability >85 %. Under simulated physiological conditions, coated sutures exhibited an average weight loss reduction of approximately 50 %. In vivo studies further demonstrated minimal inflammatory response and favorable tissue integration. These findings highlight that the PAA-Chitosan dual-layer coating significantly enhances the corrosion resistance, antibacterial properties, and biocompatibility of AZ31 Mg sutures.
术后并发症,如与缝线相关的感染和可生物降解材料的快速腐蚀,仍然是胃肠外科手术中的关键挑战。本研究调查了一种应用于AZ31镁(Mg)合金丝的新型聚丙烯酸(PAA)和壳聚糖双层涂层。通过逐层(LbL)沉积对AZ31 Mg丝进行涂层,使用聚乙烯亚胺作为底漆以促进附着。使用傅里叶变换红外光谱(FTIR)、扫描电子显微镜(SEM)、拉伸试验、析氢、稳定性研究、电化学腐蚀、抗菌试验、溶血试验、MTT试验和体内评估对涂层缝线进行表征。FTIR分析证实了PAA和壳聚糖的成功沉积,揭示了表明具有抗腐蚀和抗菌活性的官能团。涂层丝的拉伸强度从252 N显著增加到420 N。析氢减少了80%以上。电化学腐蚀表明腐蚀电流密度(Icorr)显著降低,从未涂层样品的8.805×10 A/cm²降至PAA-Ch涂层样品的1.807×10 A/cm²,腐蚀电位(Ecorr)从-1.393 V移至-2.935 V。抗菌试验显示对金黄色葡萄球菌、粪肠球菌、大肠杆菌和肺炎克雷伯菌具有广谱疗效。溶血百分比保持在2%以下,MTT试验表明具有优异的细胞相容性,细胞活力>85%。在模拟生理条件下,涂层缝线的平均重量损失减少了约50%。体内研究进一步证明炎症反应最小且组织整合良好。这些发现突出表明,PAA-壳聚糖双层涂层显著提高了AZ31 Mg缝线的耐腐蚀性、抗菌性能和生物相容性。