An introduction to medicinal, diagnostic and therapeutic uses of nanoparticles

Nanoparticles are the species i.e. atoms, molecules, polymers etc. which have overall size under 100 nm. The onedimensional nanoparticle such as nanowires and nanotubes have one dimension larger than the nanoscale and twodimensional nanomaterials such as self-assembled monolayer films have two dimensions larger than the nanoscale. The other nanoparticles are referred as zero dimensional nanomaterials because all of their dimensions are in nanoscale. The nanoparticles have emerged as important tools in medicine with wide range of clinical applications. In many cases they have been used in analyses and therapies where usual methods fail or remain ineffective. The applications of nanoparticles in diagnoses are important because when they are effective, their very less amounts can serve the purpose. In actual practice they help to detect the occurrence of disease on molecular scale. It is important to mention here that if at any stage it is detected that they are ineffective or are harmful they can be withdrawn without causing much damage. Their use provides freedom to the researchers to modify their properties such as appearance, taste, solubility etc. thereby improving the solubility of poorly soluble drugs, blood circulation, half life, drug release characteristics etc. The nanoparticles may provide more effective and more convenient route of administration because they allow targeted delivery and controlled release. This also reduces the side effects of the drugs. Their use may lower therapeutic toxicity and reduce health care costs. The imaging contrast agents based on nanoparticles have been shown to improve the sensitivity and specificity of magnetic resonance imaging. Considering the vast scope of nanomedicine we will focus on few medicinal applications of nanoparticles viz. diagnostic, therapeutic, imaging etc. The review article includes the synthesis of nanoparticles done by the researchers, their applications in medicine, their harmful effects if any and further prospects