Title: Fabrication of bienzymatic cholesterol biosensor based on gold nanoparticles decorated graphene-nanostructured polyaniline nanocomposite
Authors: Deepshikha; Ruchika Chauhan; Pratima R. Solanki; Tinku Basu
Addresses: Amity Institute of Biotechnology, Amity University Uttarpradesh, Noida, 201303, India ' Amity Institute of Nanotechnology, Amity University Uttarpradesh, Noida, 201303, India ' Amity Institute of Nanotechnology, Amity University Uttarpradesh, Noida, 201303, India ' Amity Institute of Technology, Amity University Uttarpradesh, Noida, 201303, India
Abstract: A novel amperometric cholesterol biosensor based on bienzyme system such as cholesterol oxidase (ChOx) and horseradish peroxidase (HRP) was developed based on the gold nanoparticles decorated graphene-nanostructured polyaniline nanocomposite (NSPANI/AuNP/GR) film, electrochemically deposited onto indium-tin-oxide (ITO) electrode. The cholesterol oxidase (ChOx) and horseradish peroxidase (HRP) have been coimmobilised onto the NSPANI/AuNP/GR nanocomposite electrode using gluteraldehyde as a crosslinking agent. The nanobioelectrodes ChOx-HRP/NSPANI/AuNP/GR/ITO and ChOx-/NSPANI/AuNP/GR/ITO have been characterised by differential pulse voltammetery (DPV), cyclic voltammetry (CV) and scanning electron microscopy (SEM). The bienzymatic nanobioelectrodes ChOx-HRP/NSPANI/AuNP/GR/ITO have exhibited higher sensitivity than mono enzymatic bioelectrode (ChOx-/NSPANI/AuNP/GR/ITO). Minimum interferences have been observed from ascorbic acid, uric acid, sodium pyruvate, glucose and urea for both single and bienzyme systems. It is inferred that bienzyme based nanobioelectrodes offer wider linearity (35 to 500 mg/dl), higher sensitivity (4.22 µAmM-1), high shelf life (8 weeks), low response time (19s) and high accuracy for testing of blood serum samples than mono enzyme system. Mechanism of the overall biochemical reaction has been proposed to illustrate the enhanced bio-sensing performance of the bienzyme system.
Keywords: polyaniline nanocomposites; cholesterol oxidase; ChOx; horseradish peroxidase; HRP; electrodeposition; repeatability; reusability; shelf life; bienzymatic cholesterol biosensors; gold nanoparticles; graphene; nanotechnology; indium; tin; oxide; ITO electrodes; nanobioelectrodes; bioelectrodes; nanoelectrodes; blood serum testing; biosensing; bienzymes.
International Journal of Biomedical Nanoscience and Nanotechnology, 2012 Vol.2 No.3/4, pp.251 - 275
Available online: 28 Dec 2012 *Full-text access for editors Access for subscribers Free access Comment on this article