Trace analysis of aminoglycoside antibiotics in bovine milk by MEKC with LIF detection

✍ Scribed by Juan Manuel Serrano; Manuel Silva

• Publisher: John Wiley and Sons
• Year: 2006
• Tongue: English
• Weight: 341 KB
• Volume: 27
• Category: Article
• ISSN: 0173-0835
• DOI: 10.1002/elps.200600184

✦ Synopsis

Abstract

This work describes a straightforward and sensitive method for the multi‐residue analysis of aminoglycoside antibiotics (kanamycin B, amikacin, neomycin B and paromomycin I) in bovine milk samples. The method involves the pre‐capillary derivatization of antibiotics with sulfoindocyanine succinimidyl ester (Cy5) and their separation and determination by MEKC with LIF detection. The optimum procedure includes a derivatization step of the antibiotics at 25°C for 30 min and direct injection for MEKC analysis, which is performed in about 20 min by using borate buffer (35 mM; pH 9.2) with 55 mM SDS as an anionic surfactant and 20% ACN as the organic modifier. Under these conditions, dynamic ranges of 10–500 µg/L and RSDs (within‐day precision) from 3.8 to 5.3% were obtained. These results indicate that the proposed MEKC‐LIF method is useful as a selective and sensitive tool for the determination of these antibiotics and surpasses other reported electrophoretic alternatives. Finally, the method was successfully applied to bovine milk samples after a simple solid‐phase extraction clean‐up and preconcentration procedure. The aminoglycosides were readily detected at 0.5–1.5 µg/kg levels with average recoveries ranging from 89.4 to 93.3%.