Electrochemical Study of 2,4-Dinitrophenylhydrazine as Derivatization Reagent and Aldehydes at Carbon Glassy Electrode

A selective method based on derivatization with 2,4-dinitrophenylhydrazine (DNPH) is described for the determination of several carbonyl compounds. The factors affecting the derivatization reaction of aldehyde and DNPH were investigated. The product of the derivatization reaction has been characterizedby UV/Vis spectrophotometry, NMR, infrared spectroscopy and cyclic voltammetry. Then, an electrochemical study for the determination of aldehyde-2.4-dinitrophenylhydrazone was performed at glassy carbon electrode (GCE) using square wave voltammetry (SWV). After the optimization of experimental parameters, the limits of detection (at 3 sigma) obtained for all aldehyde-2,4-DNPH were varied from 15.82 to 78.39 mu mol L-1 and relative standard deviations were between 1.8 and 4.5%. Finally, the proposed method was applied to determine the aldehydes concentration in drinking water and orange juice samples with satisfactory results.