Review on Targeted Drug Delivery Carriers Used in Nanobiomedical Applications

Targeted drug delivery (TDD) is an advanced and smart method of delivering drugs to the patients in a targeted sequence that increases the concentration of delivered drug only at the targeted body part of interest (organs/tissues/cells). This will in turn enhance efficacy of treatment by reducing side effects and the required dose of the drug. TDD ensures a certain defined minimally required constant amount of a therapeutic agent for a prolonged period of time to a targeted diseased area within the body. This helps maintain the required plasma and tissue drug levels in the body thereby avoiding any damage to the healthy tissue via the drug. Various drug carriers that are envisaged in advanced delivery systems are soluble polymers, inorganic nanoparticles, magnetic nanoparticles, biodegradable microsphere polymers (synthetic and natural), neutrophils, fibroblasts, artificial cells, lipoproteins, liposomes, micelles and immune micelle. In selecting such a vehicle, important factors to consider are chemical and physical properties drugs, side effects or cytotoxicity to healthy cells, route to be taken for the delivery of the drug, the targeted site, and the disease. As such, TDD formulations are prepared by considering the specific properties of target cells, nature of markers or transport carriers or vehicles, which convey drug to specific receptors, and ligands and physically modulated components.