A rapid UPLC method with optimized sample preparation procedures for determination of furosine in milk

Abstract

A rapid ultra-performance liquid chromatography (UPLC) method with simplified sample preparation procedures was developed for detection of furosine in milk. In tuning the sample preparation, nitrogen purging was not required for acid hydrolysis and the duration of acid hydrolysis was shortened. Purification by solid-phase extraction was also found to be unnecessary. UPLC parameters were optimized. The retention time of furosine was 1.866 min, with good separation from impurities in milk. The method was validated and shown to have good sensitivity, accuracy, precision, repeatability, and reproducibility. The limit of detection was 0.01 mg/L and the limit of quantification was 0.025 mg/L. The range of linearity was 0.5–5.0 mg/L (R2 = 0.9998). Milk samples spiked with different furosine levels showed recoveries of 83.96 %–93.51 %, with an overall mean recovery of 89.68 ± 0.06 %. The coefficients of variation for intraday, inter-day, and inter-laboratory determinations were 0.2 %–1.6 %, 0.5 %, and 4.0 %–8.1 %, respectively. The proposed method was utilized to quantify furosine in pasteurized, extended shelf life, and ultra-high-temperature-treated milk samples, which demonstrated that this novel UPLC method is effective for rapid determination of furosine in milk samples.