Simultaneous Differential Pulse Voltammetric Determination of Sulfamethoxazole and Trimethoprim on a Boron-Doped Diamond Electrode

• Published in: Electroanalysis (New York, N.Y.) N.Y.), 2009-07, Vol.21 (13), p.1475-1480
• Main Authors: Andrade, Leonardo S., Rocha-Filho, Romeu C., Cass, Quezia B., Fatibello-Filho, Orlando
• Format: Article
• Language: English
• Subjects: Boron-doped diamond; Differential pulse voltammetry; Drug design; Medicinal chemistry; Pharmaceutical formulations; Sulfamethoxazole determination; Trimethoprim determination
• ISSN: 1040-0397; 1521-4109
• DOI: 10.1002/elan.200804551

The performance of hydrogen‐ (HT) and oxygen‐terminated (OT) boron‐doped diamond (BDD) electrodes (electrochemically pretreated) on the simultaneous differential pulse voltammetric determination of sulfamethoxazole and trimethoprim in pharmaceutical products is presented. Under the optimum analytical experimental conditions, the HT‐BDD electrode presented two well‐defined oxidation peaks at 920 and 1100 mV vs. Ag/AgCl for sulfamethoxazole and trimethoprim, respectively. On the other hand, when the OT‐BDD electrode was used, the sulfamethoxazole oxidation current peak was decreased twenty fold. The calculated LOD values for sulfamethoxazole and trimethoprim using the HT‐BDD electrode were 3.65 μg L−1 and 3.92 μg L−1, respectively. The results obtained in the simultaneous determination of sulfamethoxazole and trimethoprim in three different commercial formulations were similar to those obtained using a standard HPLC method at 95% confidence level.