Silver Nanoparticle-Functionalized Medical Devices for Primary Prevention of Healthcare-Associated Infections: In Vitro Efficacy Against Multidrug-Resistant Clinical Isolates

Healthcare-associated infections represent a global public health challenge, primarily driven by biofilm-forming multidrug-resistant pathogens on medical device surfaces, leading to high morbidity, mortality, and healthcare costs. As antibiotic strategies fail due to antimicrobial resistance, this study investigates a primary-prevention nanotechnology strategy based on the photochemical functionalization of clinically relevant substrates (polyurethane venous catheters, cotton gauze, and glass-fiber HEPA filter membranes) with immobilized silver nanoparticles. While the photochemical deposition ensures a controlled silver release experimentally quantified here by ICP-MS (≈0.44 ppm·day−1) within safety thresholds, the core value of this functionalization lies in its broad-spectrum and long-term efficacy. Agar diffusion assays performed against a panel of 10 multidrug-resistant clinical isolates, including pathogens such as Pseudomonas aeruginosa, Klebsiella pneumoniae, Staphylococcus epidermidis, Candida parapsilosis, and Aspergillus sydowii, demonstrated antimicrobial activity over 15 days across all substrates. Biofilm quantification by Crystal Violet Assay revealed inhibition exceeding 97% for bacterial strains and 96% for fungal species at day 15. By preventing both bacterial and fungal colonization on diverse materials, these results validate silver-functionalized surfaces as an effective and bio sustainable approach to combat healthcare-associated infections and antimicrobial resistance. This strategy holds significant promise for translation into clinical settings, hospital air filtration systems, and wound care applications, aligning with Antimicrobial Stewardship and One Health principles.