Liquid chromatographic determination of fluorescent derivatives of six sulfonamides in bovine serum and milk

• Published in: Journal of AOAC International Vol. 78; no. 3; p. 674
• Main Authors: Tsai, C.E. (Miyazaki University, Miyazaki-shi, Japan.), Kondo, F
• Format: Journal Article
• Language: English
• Published: England 01.05.1995
• Subjects: ALIMENTOS; ANALISIS CUANTITATIVO; ANALYSE QUANTITATIVE; Animals; Cattle; CHROMATOGRAPHIE; Chromatography, Liquid - methods; CONTAMINACION; CONTAMINATION; CROMATOGRAFIA; Fluorescamine; FLUORESCENCE; FLUORESCENCIA; Fluorometry; LAIT; LECHE; LIQUIDE BIOLOGIQUE; LIQUIDOS CORPORALES; MEDICAMENT; MEDICAMENTOS; MEDICION; MESURE; Milk - chemistry; PRODUIT ALIMENTAIRE; RESIDU; RESIDUOS; Sensitivity and Specificity; SULFAMIDE; SULFONAMIDAS; Sulfonamides - analysis; Sulfonamides - blood
• ISSN: 1060-3271; 1944-7922
• DOI: 10.1093/jaoac/78.3.674

A rapid and sensitive liquid chromatographic (LC) method with fluorometric detection was developed to detect sulfadiazine, sulfathiazole, sulfamethazine, sulfamonomethoxine, sulfamethoxazole, and sulfadimethoxine residues in bovine serum and milk. p-Aminobenzoic acid (PABA) was added as an internal standard. The sulfonamides were extracted from samples and derivatized with fluorescamine, and 50 microliters was injected into a NovaPak C(18) LC column and eluted with acetonitrile-10 mM potassium phosphate (30 + 70, v/v). The sulfonamides were detected fluorometrically (excitation, 390 nm; emission, 475 nm), and their retention times ranged from 6.2 to 16.5 min without interference from coextractives. The detection limit for standard sulfonamide solution was 0.1 ng/mL; the calibration curves were linear between 1 and 100 ng/mL in the presence of PABA as internal standard. Recovery rates of sulfonamides from spiked samples (1 and 10 ppb) were 95.4-107.2 and 81.4-89.6% for serum and 80.7-91.1 and 62.6- 84.1% for milk, respectively