IMPEDIMETRIC NON-ENZYMATIC GLUCOSE SENSOR BASED ON NICKEL HYDROXIDE THIN FILM ONTO GOLD ELECTRODE

ANA L. RINALDI; ROMINA CARBALLO; ANA L. RINALDI; ROMINA CARBALLO

SENSORS AND ACTUATORS B-CHEMICAL

ELSEVIER SCIENCE SA

Lugar: Amsterdam; Año: 2016 vol. 228 p. 43 - 52

0925-4005

A non-enzymatic glucose sensor based on a thin layer of nickel immobilized on a gold electrode(EAuNi(OH)2) was used to perform impedimetric determination of glucose. The electrodeposition solu-tion, composed of 0.010 M Ni(NO3)2·6H2O and 1 M of chloride, allows only one active catalyst (NiOOH)to be present on the gold electrode surface after activation with 0.1 M KOH.Electrochemical oxidation of glucose on EAuNi(OH)2electrode was evaluated by Cyclic Voltammetry(CV) and Electrochemical Impedance Spectroscopy (EIS) in the concentration range of 0?14.8 mM of ana-lyte. Ip/v1/2vs scan rate graph shows a typical catalytic behavior by EAuNi(OH)2toward glucose oxidation.Measurements in the presence of possible interfering species (ascorbic acid, uric acid, dopamine) did notaffect the response of the analyte of interest.EIS offers good sensibility and selectivity for the glucose detection by non-enzymatic glucose sensoras an alternative to conventional methods. A single-frequency impedance method is proposed as trans-duction principle. For that, the parameters of complex impedance (module, phase, real and imaginaryimpedance) at each frequency were evaluated in function of glucose concentration and in terms of cor-relation coefficient. These analyses show a better linear response for the module of impedance (|Z|) inthe range of 0?2 mM of glucose at 0.1 Hz (R2= 0.984) with a slope of 484.7 mM−1of glucose. Finally,EAuNi(OH)2was successfully applied to the assay of glucose in blood samples.