Chemically Modified Electrode (CME) Is Applied In Food Analyse Field

When life level of people has been improved, people will pay more attention to function and safety of food. Food analyses become more and more important. In the text the application of chemically modified electrodes (CME) in food analyses has been studied.The electrochemical behavior of kojic acid with a glassy carbon (GC) electrode was investigated. The contents of kojic acid were measured by differential pulse voltammetry (DPV). However, it was not satisfied in real sample analyses. In the solution of 0.3 mol/L pH=5.0 NaAc-HAc, kojic acid was determined by semi-differential linear sweep voltammetry at a silica sol-gel modified GC electrode in the concentration range of 2×10-5—7×10-4 mol/L. The RSD for food analyses was 5.1%(n= 4) and the sol-gel modified GC electrode is stability. In the same condition, the voltammetric behavior of kojic acid at MWNTs-modified GC electrode was investigated. The oxidation peak current of kojic acid on the modified electrode increased significantly compared with that on a bare GC electrode. The peak potential did not change and the peak current was line with its concentration in the range of 1×10-5—1×10-3 mol/L in DPV mode. The RSD for sample analyses was 4.5%(n=5). The results showed the MWNTs-modified GC electrode could improve its electrochemical sensitivity and stability. It had been applied to the direct determination of kojic acid in foodA new method was proposed for the determination of maltol in food using MWNTs-modified GC electrode by DPV. In the solution of 0.3 mol/L pH=8.5 NH3-NH4Cl, the oxidation peak current of maltol on the MWNTs-modified GC electrode increased significantly compared with that on a bare GCE and the peak potential did not move. The peak current was line with its concentration in the range of...