Saluti, Giorgio, et al. Microchemical Journal, 2024, 199, 110197.
A robust liquid chromatography tandem mass spectrometry (LC-MS/MS) and liquid chromatography tandem mass spectrometry (LC-MS/MS/MS) analytical method was developed and validated for the confirmation of five nitrofuran antimicrobial metabolites (NFs) in animal muscle tissue. 1-Aminohydantoin (AHD), 3-amino-5-methylmorpholino-2-oxazolidinone (AMOZ), 3-amino-2-oxazolidinone (AOZ), 3,5-dinitrosalicylic acid hydrazide (DNSH), and semicarbazide (SEM) were validated using a matrix-integrated internal validation concept and standard addition calibration.
Standard solutions and sample preparation
Separate stock solutions of analytes and marker standard AMOZ-d5 (IS) were prepared at 1 mg mL-1 in methanol, except DNSH and DNSH-13C6 IS (0.04 mg mL-1). A spiked standard solution consisting of the five analytes and an intermediate standard solution of AMOZ-d5 and DNSH-13C6 (IS) at a concentration of 10 ng mL-1 was prepared in methanol. Sample preparation included the addition of 40 μL of the 10 ng mL-1 IS intermediate solution, an acid hydrolysis and derivatization step, and then liquid-liquid extraction of the analytes with ethyl acetate.
