Fabrication and Characterization of (Au@ Ag) Core- Shell Nanoparticles for Glucose Sensing

Abstract

Diabetes mellitus affect every organ of human body and is considered as one of the major health diseases. It is very important to continuously monitor glucose level. Nonenzymatic amperometric glucose biosensors based on Gold Silver core-shell nanoparticles were fabricated. Core-shell nanoparticles were synthesized by seed mediated method in which sodium citrate was used as a reducing and capping agent. The shape, surface plasmon resonance effect, optical properties, bond stretching and elemental composition as well as crystalline structure were noticed by using SEM, UV-Vis spectroscopy, RAMAN spectroscopy, FTIR spectroscopy, EDX and XRD techniques. The present work highlights the electrochemical response of glucose concentration by using Gold@ Silver core-shell nanoparticles based upon glassy carbon electrode which ensure the detection of glucose. Furthermore, the selectivity of the sensor against glucose was tested by using ascorbic acid and uric acid. The sensitivity of the fabricated sensors was recorded to be 0.1 μM and 6 μM for (Au@ Ag)20 and (Au@ Ag )2, respectively. The two linear responses of (Au@ Ag)20 and (Au@ Ag )2 from cyclic voltammetry ranging from 0.1mM-0.5 mM and 0.2 mM -0.5 mM and from amperometry ranging from 0.1 μM-14 mM and 6 μM -40 μM were recorded, respectively. The low detection limit, high sensitivity, selectivity, and stability of the fabricated sensor depicts that the sensor can be applied to detect blood glucose as well as noninvasive glucose detection in the body fluid such as sweat and saliva.