Nanotoxicology in Biomedical Applications

Abstract

Engineered nanomaterials are entering biomedical practice as drug carriers, imaging contrast agents, biosensors, and antimicrobial coatings, yet the toxicological profiles of many formulations remain incompletely characterised, creating regulatory uncertainty that slows clinical translation. We evaluated 220 nanotoxicology assessment programmes conducted across laboratories affiliated with the Swiss Institute of Machine Intelligence between 2015 and 2024, spanning five nanomaterial categories: metallic nanoparticles, polymeric nanocarriers, lipid-based nanoformulations, carbon-based nanomaterials, and inorganic quantum dots. A Nanotoxicology Assessment Maturity Index (NAMI) was constructed from five sub-scores -- dose-response characterisation completeness, mechanistic pathway elucidation, in vitro-to-in vivo correlation strength, chronic exposure data availability, and regulatory dossier readiness -- with weights from regression against progression to next-phase regulatory submission. NAMI correlated with regulatory advancement at r = +0.83 and discriminated advancing from stalled programmes with an AUC of 0.876. Lipid-based nanoformulations scored highest (mean NAMI 0.818), while carbon-based nanomaterials trailed at 0.588. Only 33.2 percent of programmes exceeded the 0.75 NAMI threshold. Dose-response characterisation completeness carried the largest regression weight (beta = +0.278), followed by in vitro-to-in vivo correlation strength (beta = +0.230).