Nanodelivery of drugs is an area of growing interest. Some key factors such as small size and high
surface area, along with drug loading capability, make these ideal drug delivery systems. These can
easily be modified to cater to diverse therapeutic and diagnostic applications. Nanoparticles bridge
the gap between biomedical and physical sciences since they are applicable in a wide range of
medical fields, such as nanobiotechnology, drug delivery, tissue microengineering and microfluidics.
Nanoparticles can be organic or inorganic in origin, mostly depending upon their applications.
Organic nanoparticles are biocompatible and biodegradable in nature and promote the bioavailability
of the therapeutic drug payload. Inorganic nanoparticles, on the other hand, can be employed for
medical imaging and subsequent theranostic applications. Therefore, such nanoparticles not only
conform to targeted drug delivery, but also provide a nanomedical tracking system from systemic
to cellular levels. For efficient drug delivery, site-specific nanoparticles can be loaded with various
hydrophilic or hydrophobic drugs and functionalised with one among numerous targeting ligands
such as antibodies, peptides or aptamers. Moreover, the size range of these particles lying in
nanometeric scale facilitates their ability to cross the blood-brain barrier, which is otherwise difficult
for most drugs to cross. In line with this, nanoparticle^ are also capable of penetrating tissues and.
finally, being taken up by cells.