Simultaneous quantitative analysis of 20 amino acids in food samples without derivatization using LC-MS/MS

In order to detect many kinds of amino acids with high selectivity in food samples, the LC/MS analysis have been used widely. Amino acids are high polar compound, so they are hard to be retained to reverse-phased column such as ODS (typical method in LC/MS analysis). It needs their derivartization or addition of ion pair reagent in mobile phase to retain them. For easier analysis of amino acids, it is expected to develop the method without using reagents mentioned above. This time, we tried to develop a simultaneous high sensitive analysis method of 20 amino acids by LC/MS/MS with mix-mode column (ion exchange, normal-phase) and the typical volatile mobile phase suitable for LC/MS analysis.