A Combined MRM and SIM Method for Direct Quantitative Determination of Amino Acids in Various Samples on LC/MS/MS

Quantitative analysis of amino acids in biological samples, food and nutrition products are often required in various fields from research to manufacturing. Recently, Imtakt introduced a new Intrada Amino Acid column, which is composed of a mixed stationary phase of ion exchange and normal phase, for direct separation and detection of amino acids on LC-MS without the need for pre- or post-column derivatization. This new method not only simplifies the analysis of amino acids drastically, but also reduces the running cost and enhances the applicability for various kinds of samples. We describe the applications of the Intrada Amino Acid column with using a combined MRM-SIM mode for direct analysis of 20 amino acids in a variety of samples on LC/MS/MS. The samples include from human plasma, serum, urines to wines, beers, vinegar, sports water & amino acid drink. The aim of using a combined SIM and MRM method is to increase the detection sensitivity of certain amino acids which have low sensitivities in MRM mode, mainly Glycine and a few other amino acids.