title: Fabrication of hydrogen peroxide biosensor based on Ni doped SnO2 nanoparticles.
abstract: Ni doped SnO(2) nanoparticles (0-5 wt%) have been prepared by a simple microwave irradiation (2.45 GHz) method. Powder X-ray diffraction (XRD) and transmission electron microscopy (TEM) studies confirmed the formation of rutile structure with space group (P(42)/mnm) and nanocrystalline nature of the products with spherical morphology. Direct electrochemistry of horseradish peroxidase (HRP)/nano-SnO(2) 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(-10) mol cm(-2)) has been obtained on nano-Ni doped SnO(2) as compared to the bare glassy carbon (GC) and nano-SnO(2) modified surfaces. This HRP/nano-Ni-SnO(2) film has been used for sensitive detection of H(2)O(2) by differential pulse voltammetry (DPV), which exhibited a wider linearity range from 1.0×10(-7) to 3.0×10(-4)M (R=0.9897) with a detection limit of 43 nM. The apparent Michaelis-Menten constant (K(M)(app)) of HRP on the nano-Ni-SnO(2) was estimated as 0.221 mM. This excellent performance of the fabricated biosensor is attributed to large surface-to-volume ratio and Ni doping into SnO(2) which facilitate the direct electron transfer between the redox enzyme and the surface of electrode.
authors.affiliation: Department of Bioelectronics and Biosensors, Alagappa University, Karaikudi 630003, Tamilnadu, India.
authors.forename: N
authors.initials: N
authors.lastname: Lavanya
authors.forename: S
authors.initials: S
authors.lastname: Radhakrishnan
authors.forename: C
authors.initials: C
authors.lastname: Sekar
mesh_terms: D015374:Biosensing Techniques / Q000295:instrumentation / Q000379:methods*; D004800:Enzymes, Immobilized / Q000737:chemistry; D006735:Horseradish Peroxidase / Q000737:chemistry; D006861:Hydrogen Peroxide / Q000302:isolation & purification*; D053768:Metal Nanoparticles / Q000737:chemistry*; D009532:Nickel / Q000737:chemistry; D017971:Tin Compounds / Q000737:chemistry
chemical_list: D004800:Enzymes, Immobilized; D017971:Tin Compounds; D009532:Nickel; D006861:Hydrogen Peroxide; D006735:Horseradish Peroxidase; C045358:stannic oxide