Chapter 3 - Implementation of gold and silver nanoparticles in sensing and bioengineering

Abstract

In the era of nanotechnology, nanoparticles are considerably studied as chemosensors and biosensors because of their excellent performance in terms of sensitivity, selectivity, linearity, stability, response time, and reproducibility. These nanoparticles are generally reduced metal (gold/silver) salts in fluid usually water, which provide vibrant colors with the interaction of light. The metallic nanoparticles exhibit unique traits of changing their physical, chemical, and biological properties by changing their surface-to-volume ratio: therefore, can be used for various modifications and applications. Among various metallic nanoparticles, noble metal nanoparticles are the most captivating and vivacious nanoparticles in field of applications. Some unique properties such as biocompatibility, conductivity, high density, and high surface-to-volume ratio facilitate the use of gold and silver nanoparticles in sensing. The similarity with the size of biological molecules enhances the potential use of gold and silver nanoparticles in sensing, biosensing, and medicines. Whilst the capability of gold nanoparticles to cross the blood-brain barrier to interact with DNA facilitates their use in biomedicine. Large surface area and tendency to get coated with many kinds of organic and inorganic molecules manifest their use in drug delivery systems with great efficiency. These properties lead to a broad range of applications in the field of organic photovoltaics, sensing, therapeutic agents, drug delivery, bioengineering, and many more. This book chapter focuses on the recent reports of sensing and bioengineering application of gold and silver nanoparticles.