Agriculture Reference
In-Depth Information
dendrimer has numerous chain ends; this property could also be useful for catalysis.
In addition, since three-dimensional dendrimers contain interior cavities into which
other molecules could be placed, they may be useful for drug delivery.
2.3.4 Composites
The combination of two different nanomaterials or nanomaterials with bulk-type
materials (Lin et al.
2007
) is called composites. It can be of different morpholo-
gies such as spheres, tubes, rods and prisms (Yu-Nam et al.
2008
). For example,
nanosized clays are being used now-a-days for products ranging from auto parts to
packaging materials, to enhance mechanical, thermal, barrier, and flame-retardant
properties.
3 Preparation of Different Nanomaterials
The synthesis of metal and metal oxide nanomaterials is a growing research area due
to their potential applications in the development of novel technologies. The scien-
tific and technological importance of metal (Au, Ag, Pd etc.) and metal oxide (ZnO,
SiO
2,
TiO
2,
etc.) nanomaterials has made them the subject of intensive research ow-
ing to their wonderful physical and chemical properties and also their important
applications in physical, chemical and biological field such as in nanobiotechnol-
ogy. Generally, nanomaterials are prepared by a variety of chemical methods, in-
cluding sol gel, template method, wet chemical synthesis, electrochemical method,
photochemical method, and sonochemical synthesis. However, eco-friendly and
cost-effective procedures for the synthesis of nanomaterials are of great interest to
biologists, chemists and materials scientists using non-toxic chemicals, environ-
mentally benign solvents, and renewable materials. Currently, there is growing need
to develop eco-friendly and body benign nanomaterials synthesis methods without
the use of toxic chemicals in the synthesis protocols to avoid adverse effects in
biomedical and agricultural applications. Recently, the green chemistry which aims
at reducing or eliminating substances hazardous to human health and the environ-
ment, is becoming more and more important (Poliakoff et al.
2001
,
2002
). Various
types of nanomaterials have been successfully prepared by our research group using
green chemistry route.
3.1 Gold Nanoparticles
Gold nanoparticles have been synthesized by simple and cost-effective microwave
irradiation processes with an irradiation time of 40-70 s.
