Determination of glycine in biofluid by hydrophilic interaction chromatography coupled with tandem mass spectrometry and its application to the quantification of glycine released by embryonal carcinoma stem cells

► The analysis of glycine in biological matrix by HILIC-MS/MS is firstly reported. ► The method avoids the usage of derivatization or/and ion-pairing reagents. ► The method features the direct injection of samples, with no sample pretreatment. ► ECSCs are firstly discovered to release glycine by the validated method. ► The discovery helps to improve our understanding of the novel effects of glycine.