Article

Development of Cu2O/Carbon Vulcan XC-72 as non-enzymatic sensor for glucose determination.

Chemical Engineering Department, National Research Center, Dokki, Giza, Egypt.
Biosensors & bioelectronics (Impact Factor: 5.43). 02/2011; 26(8):3542-8. DOI:10.1016/j.bios.2011.01.042
Source: PubMed

ABSTRACT A novel and stable non-enzymatic glucose sensor was developed based on the chemical reduction of Cu(2)O nanoparticles on Carbon Vulcan XC-72 using NaBH(4) as the reducing agent via the impregnation method. Different molar ratios of NaBH(4) to the copper salt were employed during the reduction step. This was found to affect the morphology; composition and structure of the prepared samples as investigated by TEM, EDX and XRD analyses. Cyclic voltammetry and chronoamperometry were applied to examine the electrocatalytic activity of the different samples of Cu(2)O/Carbon Vulcan XC-72 towards glucose oxidation in alkaline medium. The 'x70' sample got the highest oxidation current density and the lowest oxidation potential. The performance of this sensor was evaluated showing a wide linear range up to 6mM with sensitivity of 629 μA cm(-2)mM(-1) and detection limit of 2.4 μM. Its good tolerance to ascorbic acid with long-term stability elects Cu(2)O/Carbon Vulcan XC-72 as a promising glucose sensor.

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