Are Nanoparticles Useful?

Nanoparticles is a particle having one or more dimensions of the order of 100nm or less. Generally, nanoparticles have larger specific surface area compared with the bulk materials which has high surface activity and make nanoparticles to be great catalyst and good materials for air storage and low melting point products.
Besides, when particles in nano size, its physical and chemical properties will change. e.x gold nanoparticles will lose its golden luster and turn into black because gold nanoparticles has very low light reflectivity which make it to be high efficient light-heat transition materials. In a similar way, nanoparticles show special thermotic , magenetic and mechanic properties, which are widely used in metallurgy industry,magenic recording industry,ceramic industry...
What's more, nanoparticles are used in medical industry to do disease diagnosis by testing blood. Also, nanoparticles technology can prove to be very useful in cancer therapy allowing for effective and targeted drug delivery by overcoming the many biological, biophysical and biomedical barriers that the body stages against a standard intervention such as the administration of drugs or contrast agents.
Human Beings have only discover tip of the iceberg of nanoparticles.