Review—Recent Advances in Biogenic Silver Nanoparticles & NanoComposite Based Plasmonic-Colorimetric and Electrochemical Sensors

Abstract

The unique opto-electronic properties coupled with small surface of silver nanoparticles have opened the door for their use in sensing applications. Silver nanoparticles are extensively used for identification of various health and environmentally hazardous pollutants such as heavy metal ions and other harmful organic chemicals with extremely low detection limits. In recent years, the toxicity of the silver nanoparticles has further been reduced using green synthesis methods. This review, therefore, present current advances in the sensing applications of green synthesized silver nanoparticles and nanocomposites. This paper reports exclusively the synthesis of silver nanoparticles using reductants derived from biological systems especially plant extracts and other bio-safe materials. Various characterization techniques employed to ascertain the phase purity and morphological features of the silver nanoparticles have been discussed. Applications of the green synthesized silver nanoparticles for colorimetric and electrochemical sensing of various pollutants such as heavy metal ions H2O2, NH3, nitrite ions, sulfide ions, kanamycin, nitrobenzene, biomolecules such as nucleic acids, aminoamides etc have been deliberated at length. This article will act as a guide to the reader about the recent advances in colorimetric, optical, and electrochemical sensing properties of green synthesized silver nanoparticles and nanocomposites.