Copper in the Nanotechnology Era: A Systematic Review of Antimicrobial Implications

Abstract

The global rise in antimicrobial resistance has highlighted the importance of complementary, non-antibiotic infection-prevention techniques. Due to their broad-spectrum activity, versatility, and suitability for surface, textile, wound-care, and filtration applications, copper-based nanomaterials (CuNMs) have emerged as potential antimicrobial platforms. This systematic review, conducted in accordance with PRISMA guidelines, provides evidence from 46 peer-reviewed studies on the antimicrobial mechanisms, application settings, safety considerations, and environmental consequences of CuNM technology. CuNMs can inhibit bacteria, fungi, and viruses through membrane disruption, Cu⁺/Cu²⁺ ion release, ROS generation, protein dysfunction, nucleic acid damage, and biofilm suppression, according to the studies included. Several platforms, including copper oxide nanoparticles, copper sulfide nanostructures, copper-containing nanozymes, hydrogels, coatings, textiles, and filtration materials, demonstrated high antibacterial or antibiofilm activity in experimental or preclinical studies. However, the significant variation in material characterization, antimicrobial testing methodologies, exposure settings, and outcome reporting precludes direct quantitative comparisons between investigations. Concerns about cytotoxicity, environmental persistence, copper ion release, durability, and regulatory uncertainty emphasize the importance of standardized characterization, long-term safety evaluation, environmental fate assessment, and translational validation. In general, CuNMs are potential infection-prevention platforms that have not yet undergone complete validation. Further research is needed to standardize material characterization and antimicrobial testing, evaluate long-term safety and environmental fate, assess durability under real-use conditions, and support translational validation before widespread clinical or public-health implementation can be recommended.