Determination of Phenylethanolamine A Residues in Milk by Solid Phase Extraction-Liquid Chromatography Tandem Mass Spectrometry

Abstract

A method was established for the determination of phenethanolamine A residue in milk by solid phase extraction, liquid chromatography-tandem mass spectrometry. The samples were extracted with ammonium acetate buffer solution under the condition of enzymatic hydrolysis and purified by MCX solid phase extraction column. The eluent was blown dry with nitrogen at 45℃ and dissolved with 1.0 mL 0.1% formic acid solution. The samples were isolated by Poroshell 120EC-C18, 100 mm ×3.0 mm (i.d.), 2.7 μm column, and then determined by mass spectrometry in multiple reaction monitoring mode, and quantified by internal standard method. The results showed that phenethanolamine A had good linear relationship in the concentration range of 0.5-50.0 μg/L, the correlation coefficient r=0.9984, the limit of detection was 0.17 μg/kg, and the limit of quantitation was 0.57 μg/kg. The average recovery was 98.3-108.7% and the precision was 2.4-3.7% at different supplemental levels. The established method can purify the samples effectively, improve the detection efficiency, and is suitable for the detection of phenethanolamine A residue in milk.