Nanocarrier-Mediated Antimicrobial Delivery Against Resistant Eskape Pathogens: Experimental Evidence and Translational Challenges

Abstract

Antimicrobial resistance among ESKAPE pathogens has reduced the reliability of several established treatments and intensified interest in nanotechnology-based antimicrobial delivery. This narrative review critically examines experimental nanocarriers used to deliver antimicrobial payloads against resistant ESKAPE organisms. A focused literature search of PubMed/MEDLINE, Scopus, Web of Science and Embase was undertaken using terms related to nanocarriers, ESKAPE organisms and antimicrobial resistance. Eight illustrative experimental studies were synthesized, covering mesoporous silica nanoparticles, liposomes, polymeric micelles, polymeric nanoparticles, albumin nanoparticles and nanoemulsions. Reported benefits included lower inhibitory concentrations, sustained release, improved local delivery, suppression of virulence and increased inhibition of biofilm formation. The magnitude of benefit was formulation-dependent. Some liposomal meropenem preparations showed no improvement or performed worse than free drug, demonstrating that encapsulation is not inherently advantageous. Most evidence was generated in vitro, animal validation was uncommon and no clinical trial evidence was identified among the selected studies. Resistance status, dose equivalence and biofilm endpoints were also inconsistently reported. Current evidence supports cautious, formulationspecific development rather than a general conclusion that nanocarriers reverse antimicrobial resistance. Standardized comparisons, maturebiofilm models, pharmacokinetic evaluation, organ-specific safety testing and reproducible manufacturing are required before clinical translation.