SIlver Nanoparticles

Silver nanoparticles are found to have wide applications in diverse

areas like optical receptors, bio-labelling sensors, bio active materials,

solar energy conversion, signal enhancers in SERS based enzyme

Immunoassay [1]. Silver nano particles exhibit high antimicrobial and

anti cancer activities. The fabrication of silver nanoparticles and nano

structures has aroused the interest of many researchers. Various synthesis

methods have also been developed.

Among the existing synthesis methods, mostly chemical methods,

which involve toxic and potentially hazardous chemicals, are mostly

used. The green synthesis based on green chemistry, replaces hazardous

chemicals by environmental friendly products. Green Chemistry is the

utilization of a set of principles that reduces or eliminates the use or

generation of hazardous substances. Biological methods are better substitute

for the chemical procedures, because they are convenient, widely

distributed along the ecological boundaries and are safe to handle.

The objective of the present work is to synthesize silver nanoparticles

by the methods designed on the principles of green chemistry. The

designed methods focus mainly on control over the size of the nanoparticles.

This work also includes the study of the effect of current (through

the circuit), temperature, strength of the precursor, reducing/capping

agents and concentration of the capping agents on nanoparticles and the

nanostructures. The as-synthesized silver nanoparticles are analyzed

using various characterization techniques e.g. XRD, TEM, UV-Visible

spectroscopy etc. This work finds application of the silver nanoparticles

in biomedical field. The findings of the tests conducted for antibacterial

properties show almost 100% killing efficiency against E. coli, S.

Aureus, S. Typhi and P. Aeruginosa. In case of testing the samples for

anti-cancer activities, the results show 80-98% growth inhibition for

MC F-7 Breast Cancer cell lines and He-La cervical cancer cell lines.

The monograph contains 5 chapters. Chapter 1 gives a brief introduction

of silver nanoparticles, covering their properties, synthesis

approaches and applications.

Chapter 2 introduces historical background of silver and narrates

exhaustive literature review conducted during the research. The chapter

gives details about the existing physical, chemical and biological

approaches and identifies the gap in the present synthesis methods. It

justifies the need and importance of the present work.

Chapter 3 gives details about the materials and the synthesis methods

used in the present research work. It describes the five different methods,

designed in the present research work, with varying parameters

that control the morphology of the nanoparticles and nanostructures.

Chapter 4 gives the results and discussions in details regarding the

as-synthesized silver nanoparticles. The results are analyzed and discussed,

sequentially according to the five methods.

Chapter 5 provides summary and conclusion of the present research

work and the scope of future work.