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

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 degrees 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 microg/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 microg/kg levels with average recoveries ranging from 89.4 to 93.3%.

Combining classification and regression approaches for the quantification of highly overlapping capillary electrophoresis peaks by using evolutionary sigmoidal and product unit neural networks

“…To obtain analytical data, 55 electropherograms provided by samples containing amikacin (15-300 mg/L), paromomycin (10-200 mg/L) and mixtures of both antibiotics with uniformly distributed concentrations of them (30-300 and 20-200 mg/L, respectively) were prepared in duplicate, as described elsewhere [34], by using 35 mM sodium borate at pH 9.0 as background electrolyte.…”

“…To test proposed approaches, two aminoglycoside antibiotics, amikacin and paramomycin, were quantified in mixtures using only the analytical information provided by their overlapped CZE peaks (t i ;S t i : first-order data) registered with a laser-induced fluorescence (LIF) detector. Further details on the analytical methodology are described in a previous paper [34]. Several chemical and chemometric strategies were merged in the proposed approaches:…”

Use of SDS micelles for improving sensitivity, resolution, and speed in the analysis of β‐lactam antibiotics in environmental waters by SPE and CE

“…Thus, the same experimental conditions as those reported earlier for other amino compounds [34,35] were obtained for the kinetics of the labeling reaction (257C and 30 min) and for the optimum concentration of the label (concretely 40 mM). The composition of the derivatization borate buffer was optimized by varying the pH and the concentration of borate over the range of 7.5-10.0 and 5-60 mM, respectively.…”

Determination of additives and organic contaminants in food by CE and CEC

“…Other classes of antibiotics that have been analysed by CE include the tetracyclines [80,81], sulphonamides [82][83][84][85], aminoglycosides [86], nitrofurans [87] and penicillins [88]. Hernandez et al [80] used a 20 mM sodium carbonate (pH 11.2) buffer containing 1 mM EDTA to analyse the most commonly used tetracycline, oxytetracycline.…”

“…Serrano and Silva [86] reported the first application of CE, and specifically MEKC, to the determination of aminoglycoside antibiotics in bovine milk. As aminoglycosides do not absorb strongly, they were derivatised (precapillary) with sulphoindocyanine succinimidyl ester and subsequently determined with LIF detection.…”