The demand for novel drug delivery technologies is ever increasing though majority of the drugs are administered via oral, inhalation, transdermal and parenteral route. However, there are large numbers of therapies, particularly protein-based, gene-based and vaccine-based that cannot be delivered by this route for example insulin, growth hormones and other similar biologics. This emerging technique is a major sector in drug delivering system. It offers numbers of benefits for instances, reduced needle phobia, better patient compliance and reduce risk of needlestick injury. Moreover, this work...