Fabrication of hydrogen peroxide biosensor based on Ni doped SnO2 nanoparticles

• Published in: Biosensors & bioelectronics 2012-06, Vol.36 (1), p.41-47
• Main Authors: Lavanya, N., Radhakrishnan, S., Sekar, C.
• Format: Article
• Language: English
• Subjects: Biological and medical sciences; Biosensing Techniques - instrumentation; Biosensing Techniques - methods; Biosensors; Biotechnology; Enzymes, Immobilized - chemistry; Fundamental and applied biological sciences. Psychology; Horseradish Peroxidase - chemistry; Hydrogen peroxide; Hydrogen Peroxide - isolation & purification; Metal Nanoparticles - chemistry; Methods. Procedures. Technologies; Microwave irradiation; Ni doping; Nickel - chemistry; Tin Compounds - chemistry; Tin oxide; Various methods and equipments
• ISSN: 0956-5663; 1873-4235
• DOI: 10.1016/j.bios.2012.03.035

Ni doped SnO2 nanoparticles (0–5wt%) have been prepared by a simple microwave irradiation (2.45GHz) method. Powder X-ray diffraction (XRD) and transmission electron microscopy (TEM) studies confirmed the formation of rutile structure with space group (P42/mnm) and nanocrystalline nature of the products with spherical morphology. Direct electrochemistry of horseradish peroxidase (HRP)/nano-SnO2 composite has been studied. The immobilized enzyme retained its bioactivity, exhibited a surface confined, reversible one-proton and one-electron transfer reaction, and had good stability, activity and a fast heterogeneous electron transfer rate. A significant enzyme loading (3.374×10−10molcm−2) has been obtained on nano-Ni doped SnO2 as compared to the bare glassy carbon (GC) and nano-SnO2 modified surfaces. This HRP/nano-Ni–SnO2 film has been used for sensitive detection of H2O2 by differential pulse voltammetry (DPV), which exhibited a wider linearity range from 1.0×10−7 to 3.0×10−4M (R=0.9897) with a detection limit of 43nM. The apparent Michaelis–Menten constant (KMapp) of HRP on the nano-Ni–SnO2 was estimated as 0.221mM. This excellent performance of the fabricated biosensor is attributed to large surface-to-volume ratio and Ni doping into SnO2 which facilitate the direct electron transfer between the redox enzyme and the surface of electrode. ► This paper presents a simple and mediator-free H2O2 detection using HRP/Ni–SnO2 bioelectrode. ► This new biosensor exhibits a wider linear range, good stability and reproducibility. ► Ni doping into SnO2 facilitates direct electron transfer between enzyme and electrode surface. ► Spherical shaped Ni–SnO2 nanoparticles was prepared by a simple microwave irradiation method.