Chinese Journal of Chromatography ›› 2013, Vol. 31 ›› Issue (8): 781-785.DOI: 10.3724/SP.J.1123.2012.12051

• Technical Notes • Previous Articles     Next Articles

Analysis of sialic acid in infant formulas using ultra performance liquid chromatography-triple quadrupole mass spectrometry

XIE Honglei1,2, LI Chun1, LIU Ning1,2   

  1. 1. College of Food Sciences, Northeast Agricultural University, Key Laboratory of Dairy Science, Ministry of Education, Harbin 150030, China;
    2. National Dairy Engineering & Technical Research Center, Heilongjiang Dairy Industry Technical Development Center, Harbin 150086, China
  • Received:2012-12-28 Revised:2013-02-01 Online:2013-08-28 Published:2013-09-29
  • Contact: O658

Abstract:

The method for analysing sialic acid in infant formulas by ultra performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) has been established. Sialic acid in milk was released via acid hydrolysis, and purified by an HLB solid phase extraction cartridge. The UPLC separation was performed on an ACQUITY UPLCTM BEH HILIC column (50 mm×2.1 mm, 1.7 μm) utilizing a gradient elution program of acetonitrile and water (containing 0.1% formic acid) as the mobile phases at a flow rate of 0.25 mL/min. Injection volume and column temperature were set at 5 μL and 30℃, respectively. The identification and quantification were achieved by using electrospray ionisation (ESI)-MS/MS in positive ion mode and multiple reaction monitoring (MRM) mode. The linear range was from 0.05 to 5.0 mg/L for sialic acid and the correlation coefficient (R2) was greater than 0.99. The average recoveries spiked at the four concentration levels of 0.1, 0.5, 2.5 and 5.0 mg/L ranged between 84.3% and 98.9% with the relative standard deviations from 4.9% to 8.2%. The limit of detection was 0.01 mg/L. Therefore, this method has the characteristics of simple operation, high reproducibility and sensitivity. It can be widely applied to determine the total contents of sialic acid in infant formula, cow milk and human milk.

Key words: infant formula, sialic acid, ultra performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS)

CLC Number: