Abstract

In this paper, sonochemical synthesized nanocomposite was used in the construction of an electrochemical sensor. Decorated carbon nanoonions (CNOs) with nickel molybdate (NiMoO4) and manganese tungstate (MnWO4) nanocomposite were used to modify the glassy carbon electrode (GCE). The high conductivity and large surface area of the CNOs and the electrocatalytic effect of NiMoO4 and MnWO4 nanocomposite provide a synergistic effect on the electrooxidation processes. The modified GCE surface with a synthesized nanocomposite of CNO-NiMoO4-MnWO4 was used to determine ascorbic acid using differential pulse voltammetry (DPV) method. The developed ascorbic acid sensor displayed a wide dynamic calibration range (1-100 mu M) with trace level LOD (0.33 mu M) and appropriate sensitivity (0.1768 mu A mu M(-1)cm(-2)). The determination of ascorbic acid in the serum and urine as the real samples exhibited a reasonable relative recovery in the range of 100-104.