Recent Advances and Biomedical Applications of Nanoparticles as Drug Delivery Systems: A Comprehensive Review

Nanotechnology has improved the solubility, bioavailability, and controlled release of poorly soluble drugs and reduced off-target toxicity by precision targeting in medicine, food preservation, and industry for 40 years. This research studied polymeric, liposomal, and mesoporous nanoparticles (NPs) of structural features, fabrication methods, biological interactions, and therapeutic uses for drug transport efficiency and long-term safety. The experimental and clinical data on particle size, shape, surface chemistry, encapsulation techniques, drug transport kinetics, biodistribution, and cytotoxic responses both in vitro and in vivo for the conventional formulations. After 48 hours, poly(isohexylcyanoacrylate) nanocarriers delivered 56% of the injected dose to the liver and 1.6% to tumors, whereas liposomal doxorubicin (Doxil) increased tumor formation and lowered systemic toxicity by reduced macrophage clearance and cytotoxicity, PEG-coated NPs boosted tumor uptake and circulation. Silver or zinc oxide NPs prevented microbial degradation in strawberries, asparagus, and chicken, whereas mesoporous silica carriers stabilized hydrophobic agents and controlled payload release. The AuNPs and high-aspect-ratio particles generated oxidative stress and mitochondrial damage, affecting cytotoxicity. Thus, NPs increase therapeutic index but need surface property and release profile adjustment to address immune recognition, organ accumulation, and chronic toxicity.