Voltammetric determination of sulfanilamide using a cobalt phthalocyanine chitosan composite

• Published in: Monatshefte für Chemie Vol. 152; no. 8; pp. 895 - 902
• Main Authors: de Moura Junior, Flaudiner Gomes, Veloso, William Barros, de Oliveira Junior, José Antonio, Kraatz, Heinz-Bernhard, da Silva, Iranaldo Santos, Dantas, Luiza Maria Ferreira
• Format: Journal Article
• Language: English
• Published: Vienna Springer Vienna 01.08.2021; Springer Nature B.V
• Subjects: Analytical Chemistry; Chemistry; Chemistry and Materials Science; Chemistry/Food Science; Chitosan; Cobalt; Glassy carbon; Inorganic Chemistry; Linearity; Organic Chemistry; Original Paper; Pharmaceuticals; Physical Chemistry; Silver chloride; Spectrophotometry; Theoretical and Computational Chemistry; Urine; Voltammetry; Cobalt phthalocyanine; Chitosan; Composite; Differential pulse voltammetry; Sulfanilamide
• ISSN: 0026-9247; 1434-4475
• DOI: 10.1007/s00706-021-02812-9

In this paper, a composite based on chitosan and cobalt phthalocyanine immobilized onto a glassy carbon electrode is presented for the sensitive determination of sulfanilamide in pharmaceutical and urine samples. The modification performed on the electrode surface, by the deposition of this composite, exhibits an irreversible anodic peak at 0.97 V vs. Ag/AgCl, KCl sat in phosphate buffer at pH 7.00 for sulfanilamide. Results show that peak potential is influenced linearly by the pH of the supporting electrolyte, exhibiting a slope of 0.054 V/pH. Using differential pulse voltammetry, detection of sulfanilamide was possible in a linear range from 1.00 to 53.00 μmol dm −3 with a detection limit and quantification limit of 0.27 and 0.91 μmol dm −3 , respectively. Importantly, the sensor showed practical applications as an analytical tool for the quantification of sulfanilamide in pharmaceutical formulations and urine samples. The electrochemical approach detailed here has been validated to drug samples using a spectrophotometric method. The method proposed presents good linearity, low quantification and detection limits being of excellent applicability in pharmaceutical and urine samples. Graphic abstract