Optimization and validation of HRLC-MS method to identify and quantify triacylglycerol molecular species in human milk

Abstract

Study of the determination of triacylglycerols (TAG) molecular species in human milk is necessary for understanding the absorption of human milk fat as well as designing milk fats for infant formulas. The aim of the present study was to optimize fat extraction and validate a high resolution liquid chromatography-mass spectrometry (HRLC-MS) method to identify and quantify TAG in human milk. Intensity, repeatability, intermediate reproducibility, and recovery values were calculated, and a large sample set of human milk was analyzed. Each value for matrix effect of internal standard (IS) or standard solution (STD) in human milk during fat extraction ranged from 78 to 106% and from 56 to 107%, respectively, indicating that no matrix effect was found except for with CCC. For linearity of the method, correlation coefficient (r 2 ) values were found to range from 0.9991 to 0.9999. Recovery values were 88 and 116% for each STD at three different concentrations. Except for c 0 c 0 c 0 and LLL, the repeatability and intermediate reproducibility values were within 20% and 30%, respectively, indicating that the method was precise. The validated HRLC-MS method was applied to quantify TAG molecular species from human milk as a quality control (QC). Among the 21 quantified TAG, POL, PPO, PLS and OOP were predominant, ranging from 0.01 to 11.0 mg L À1 . TAG with short chain acyl, such as c 0 c 0 c 0 , MOB, and LLL, were quantified with low amounts in QC (between 0.01 and 0.06 mg L À1 ). The results from the current study validate the fat extraction method followed by HRLC-MS for the efficient identification and quantification of TAG molecular species in human milk samples.

Triacylglycerol Profile of Summer and Winter Bovine Milk Fat and the Feasibility of Triacylglycerol Fragmentation

“…This showed that there was a large variation within and among days. The overall variation in our study was similar to other studies on molecular species of TAG …”

Selective Identification of Organic Iodine Compounds Using Liquid Chromatography–High Resolution Mass Spectrometry

“…The evolution of high-resolution mass spectrometry (HRMS) offers the prospect of the identification of unknown compounds in different matrixes at low concentrations. − In 2013, the Juliane group developed strategies for characterizing polar organic contamination in wastewater using HRMS and proposed a level system for the identification of small molecules via HRMS, bringing chemists closer to the identification of unknown compounds . In 2014, N.S.…”

Comparative Analysis of Triglycerides From Different Regions and Mature Lactation Periods in Chinese Human Milk Project (CHMP) Study

“… a B, butanoic acid; Ca, capric acid; La, lauric acid; M, myristic acid; Pe, pentadecanoic acid; P, palmitic acid; Po, palmitoleic acid; S, stearic acid; O, oleic acid; L, linoleic acid; Ln, linolenic acid; A, arachidic acid; E, Eicosenoic acid; B′, Behenic acid; –, unknown . b References for each country: Spain: Pons et al ( 15 ); Morera et al ( 4 ); Isabel Ten-Doménech et al ( 14 ); Denmark: Zou et al ( 5 ); America: Kim et al ( 16 ); China (previous studies): Tu et al ( 10 ); Yuan et al ( 9 ); Chen et al ( 11 ). Finland: Fabritius et al ( 17 ) .…”

“… b References for each country: Spain: Pons et al ( 15 ); Morera et al ( 4 ); Isabel Ten-Doménech et al ( 14 ); Denmark: Zou et al ( 5 ); America: Kim et al ( 16 ); China (previous studies): Tu et al ( 10 ); Yuan et al ( 9 ); Chen et al ( 11 ). Finland: Fabritius et al ( 17 ) .…”