The pharmaceutical industry has witnessed a huge revolution in the past few
decades due to the discovery of various novel drugs for the treatment of several lifethreatening ailments. However, there is a continued interest in exploring nature for
inventing therapeutically active novel compounds. Among the various natural resources,
plants constitute an invaluable source of bioactive molecules. Numerous studies have
illustrated the exceptional therapeutic efficacy of phytochemicals against various
diseases. Some of the well-known drugs, such as paclitaxel, vincristine, vinblastine, etc.,
which can potentially be used in cancer therapy, were first isolated from plants. Later,
several other drug-active molecules, which have demonstrated promising therapeutic
effects, were discovered. Despite their outstanding antimicrobial, antidiabetic, and
anticancer effects in vitro, most of these molecules fail to achieve a similar effect in vivo,
mainly due to their poor aqueous solubility and bioavailability. The advent of
nanotechnology and the application of nano-drug delivery carriers have significantly
revolutionized the biomedical industry. Numerous studies indicate the successful
utilization of nanoparticles for theragnostic applications. Nanoparticles having a size of
approximately 507250 nm can efficiently interact with cellular structures, eliciting
desirable therapeutic effects. Apart from improving the aqueous dispersibility and
stability of drugs, nanoparticles enable cell-specific as well as receptor-specific drug
targeting, thereby reducing the off-target effects. Moreover, the stealthy nature of
surface-modified nanoparticles, in combination with the controlled release of
encapsulated drugs, enables prolonged therapeutic activity in vivo. This chapter presents
an updated summary of the applications and challenges of various nano-drug carrier
systems for the delivery of natural bioactive principles.
Keywords: Nanoparticles, Natural compounds, Pharmacokinetics, Phytochemicals, Plants.
