López-López A, Castellote-Bargalló A I, López-Sabater M C
Dept. Nutrició i Bromatologia, Centre de Referència en Tecnologia dels Aliments, Facultat de Farmàcia, Universitat de Barcelona, Spain.
J Chromatogr B Biomed Sci Appl. 2001 Aug 25;760(1):97-105. doi: 10.1016/s0378-4347(01)00257-2.
An alternative method to determine the sn-2 monopalmitin in infant formulas was developed and validated. This method offers many advantages over the traditional methods. It follows the official method in the first steps, purification of the fat or oil through an alumina column, and subsequently the triglycerides are incubated with pancreatic lipase in order to obtain the sn-2 monoglycerides. In traditional methods the sn-2 monoglycerides are separated by preparative thin-layer chromatography and then, the 2-monoglycerides are converted into the corresponding fatty acid methyl esters and analysed by gas chromatography. In our method, separation, quantification and identification of the sn-2 monoglycerides were achieved by high-performance liquid chromatography with evaporative light-scattering detection. The detection limit (0.19 microg), quantification limit (0.38 microg), linearity range (r=0.999, range 1-200 microg) and precision (SD=1.10) show the suitability of the proposed method. This method is faster, cheaper and simple and does not consume large quantities of reagents and materials.
开发并验证了一种测定婴儿配方奶粉中sn-2单棕榈酸甘油酯的替代方法。与传统方法相比，该方法具有许多优点。它在第一步遵循官方方法，通过氧化铝柱对脂肪或油进行纯化，随后将甘油三酯与胰脂肪酶一起孵育以获得sn-2甘油单酯。在传统方法中，sn-2甘油单酯通过制备型薄层色谱法分离，然后将2-甘油单酯转化为相应的脂肪酸甲酯并通过气相色谱法进行分析。在我们的方法中，通过带有蒸发光散射检测的高效液相色谱法实现了sn-2甘油单酯的分离、定量和鉴定。检测限（0.19微克）、定量限（0.38微克）、线性范围（r = 0.999，范围1 - 200微克）和精密度（SD = 1.10）表明了所提出方法的适用性。该方法更快、更便宜且简单，并且不消耗大量试剂和材料。
