Herbal medicines have been widely used around the world
since ancient times. Medicinal plants are most effective when their
active constituent reach at the site of action. Most of plant contains
flavonoids, tannins, and terpenoids, which are hydrophilic and
unable to cross the lipid membranes of the cells so poor absorption,
results in less bio availability and efficacy hence need to take in high
dose and frequency of dose also increases. If they are formulated
using nanotechnology, due to nano ¬structured systems might
be able to potentiate the action of plant extracts also reduce the
required dose and side effects, and improving activity. Research
has shown that use of nanotechnology and formulations like nano
liposomes, nano emulsions, lipid nanocarries, phytosomes, micelles
and poly (lactic-co-glycolic acid) (PLGA) nanoparticles beneficial in
case of phyto constituent they increases the rate of absorption bio
availability and result in better effect of herbal medicines [1-10].
The Techniques Commonly Used for the Formulation
are:
a) High-pressure homogenization methods
b) Complex coacervation method
c) Co-precipitation method
d) Salting-out method
e) Nano precipitation method or solvent displacement
method
f) Solvent emulsification-diffusion method
Types of Nano Pharmaceuticals
a) Polymeric nanoparticles
b) Solid lipid nanoparticles
c) Magnetic nanoparticles
d) Metal and inorganic nanoparticles
e) Quantum dots
f) Polymeric micelles
g) Phospholipids micelles
h) Colloidal nano-liposomes
i) Dendrimers
Table 1: Some examples of nano formulations related to phyto constituents.
Nanotechnology has potential future for enhancing the activity
and overcoming problems associated with herbal medicines
and phyto constituents Table 1. By applying nanotechnology
principles it is possible to reduce the amount of drug to be loaded
and hence prevent many dose-related adverse reactions. Several
excellent phyto constituents have been successfully delivered
using nanotechnology currently, not many products are available
for clinical use, but looking at the amount of research activity
happening in this field, the next few years many products being
launched in the market for clinical use.