Abstract: A high performance liquid chromatography-fluorescence detection (HPLC-FLD) method was developed for the qualitative and quantitative analysis of the sialic acids N-acetylneuraminic acid (Neu5Ac) and N-glycolylneuraminic acid (Neu5Gc) in red meat and its processed products. Single factor experiments were carried out to optimize the derivatization and acid hydrolysis conditions. Besides, ultrasound-assisted acidification was used to shorten the acidification time. It was found that the optimal sample preparation procedure involved ultrasound-assisted acidification time for 30 min with hydrochloric acid as the hydrolysis reagent and derivatization for 120 min with the same volume of 13 mmol/L 4,5-methylenedioxy-1,2-phenylenediamine dihydrochloride (DMB) as the derivatization reagent. The calibration curves for Neu5Ac and Neu5Gc displayed good linearity in the range of 0.1–10 μg/mL. The recoveries were in the range of 91.2%–119.7%. The limits of detection (LODs) for Neu5Ac and Neu5Gc were 0.003 and 0.01 mg/kg, respectively. The precision expressed as relative standard deviations (RSDs) for the two sialic acids was in the range of 0.7%–1.8% and the repeatability RSDs were 1.4% and 1.2%, respectively. The HPLC-FLD method has the characteristics of high sensitivity, short analysis time, and good repeatability and accuracy.

Key words: high performance liquid chromatography-fluorescence detection; red meat; processed meat products; N-acetylneuraminic acid; N-glycolylneuraminic acid