Nanotechnology as a Promising Approach to Combat Multidrug Resistant Bacteria: A Comprehensive Review and Future Perspectives

The widespread rise of antibiotic resistance poses a serious global health threat, contributing to millions of deaths worldwide and driving the emergence of multidrug-resistant (MDR) and extensively drug-resistant (XDR) bacteria. Biofilm formation exacerbates this problem, increasing tolerance to antibiotics by up to 1000-fold. With few novel antimicrobials in development, nanotechnology offers promising strategies for prevention and treatment of MDR and biofilm-associated infections. Nanomaterial-based therapeutics can circumvent conventional resistance pathways, enhance targeted delivery and bioavailability, and directly attack bacterial cells and biofilms through multiple mechanisms. This review summarizes the development and mechanisms of antibiotic resistance, the spread and impact of MDR/XDR infections, types and formulations of nanoparticles (NPs), and their antibacterial mechanisms. It contrasts free antibiotics with nanoantibiotics and highlights synergistic combinations against planktonic, intracellular bacteria, and biofilms. Finally, it discusses strengths, limitations, and future perspectives in applying nanotechnology against bacterial infections.