The use of composite electrode in voltammetric analysis of tetracyclines in biological and environmental samples

Author(s)

Carolina Maria Fioramonti Calixto

• Document type: Doctoral Thesis
• Press: São Carlos.
• Institution: Universidade de São Paulo (USP). Instituto de Química de São Carlos (IQSC/BT)
• Defense date: 2013-01-24

Examining board members

Eder Tadeu Gomes Cavalheiro; Lucio Angnes; Luiz Henrique Dall\'Antonia; Sergio Antonio Spinola Machado; Marcos Fernando de Souza Teixeira

• Advisor: Eder Tadeu Gomes Cavalheiro

Abstract

A bare graphite-polyurethane composite electrode 60% (graphite, m/m) (GPUE) was evaluated in the determination of tetracycline (TC) class antibiotics in natural water as well as, in human and bovine urine and in milk samples. Thus, a DPV procedure was optimized for the determination of tetracycline, oxytetracycline (OTC) and chlortetracycline (CTC) antibiotics in phosphate buffer 0.10 mol L-1 pH 2.3, resulting in LOD of 2.6 µmol L-1, 1.7 µmol L-1 and 0.82 µmol L-1, respectively. During the determination of TC and OTC in the water samples, recoveries between 92.6 and 100% were found, after pre-concentration stage. The urine samples were submitted to acidification followed by centrifugation to remove solids and proteins. During the determination of TC and OTC in urine samples, after pre-treatment of urine, recoveries between 96 and 100% were found. The composite electrode was also evaluated in the determination of TC in the bovine and human milk samples. During the determination of TC in milk, recoveries between 76 and 103% were found for bovine milk and recoveries between 91 and 100% were found for human milk after pre-concentration stage, showing the feasibility of the procedure. (AU)

• FAPESP's process: 08/02590-1 - Using composite electrodes in the voltammetric determination of pharmaceuticals in biological and/or environmental samples.
• Grantee: Carolina Maria Fioramonti Calixto
• Support Opportunities: Scholarships in Brazil - Doctorate