The Role of Nanotechnology in Targeting Viral Infections at the Cellular Level

Introduction: To critically synthesise evidence on how nanotechnology can be used to prevent viral entry, deliver antiviral agents to infected cells, modulate intracellular antiviral processes and improve the safety or effectiveness of antiviral therapy. Methods: We conducted a narrative review using the literature in the original manuscript as the core evidence base. We reorganised the evidence around the viral life cycle and the nanoparticle–cell interface, with an emphasis on nanoparticle composition, surface functionalisation, cellular uptake, drug and nucleic-acid delivery, safety, manufacturing, and translation. Bibliographic records were also checked during revision, and the implications for health systems in the Global South were explicitly considered. Synthesis: Inorganic, lipid, polymeric and hybrid nanoparticles can interact with viruses or host cells through adsorption, receptor targeting, endocytosis, endosomal trafficking and controlled intracellular release. Experimental evidence supports applications in viral neutralisation, inhibition of entry, delivery of antiretroviral and other antiviral agents, vaccine development and diagnostic detection. However, much of the evidence remains preclinical. Heterogeneity in particle size, surface chemistry, formulation, dose and experimental models complicates comparisons across studies. Toxicity, reproducible scale-up, stability, regulatory requirements and cost remain important barriers to clinical implementation. Conclusion: Nanotechnology provides a versatile platform for antiviral intervention, but biological plausibility should not be equated with clinical effectiveness. Future work should prioritise reproducible formulations, rigorous toxicology, clinically relevant efficacy studies and manufacturing pathways that are affordable and feasible in the Global South.