Use of the oxidizing effect of copper (II) to determine 2,4-dinitrophenylhydrazine at glassy electrode by chronoamperometry

• The glassy electrode was used to oxidize 2,4-dinitrophenylhydrazine (DNPH);
• Reaction of copper and DNPH was investigated by spectrophotometer UV/Vis;
• The oxidizing effect of copper was used to determine DNPH by chronoamperometry;
• The glassy electrode allied to copper was tested to detect DNPH in industrial water.

A glassy carbon electrode was used and challenged for the determination of 2,4-dinitrophenylhydrazine (DNPH). This probe showed a significantly enhanced electrochemical activity when it tested with copper (II). When challenged in amperometric batch mode, the response was stable and showed a linear dependence up to 1 × 10− 5 mol L− 1 of DNPH. The very high sensitivity toward copper (96.3 mA mol− 1 L cm− 2) was then used as the basis for developing an analytical method for DNPH detection since a non electroactive compound is formed in the presence of the copper. By selecting an appropriate concentration of copper, a concentration of DNPH as low 1.0 × 10− 8 mol L− 1 was detected. Satisfactory recovery was obtained when the system was tested in industrial water samples.