Separation of Isomers L-Alanine and Sarcosine in Urine by Electrospray Ionization and Tandem Differential Mobility Analysis-Mass Spectrometry

Sarcosine, an isomer of L-alanine, has been proposed as a prostate cancer progression biomarker [ 1]. Both compounds are detected in urine, where the measured sarcosine/alanine ratio has been found to be higher in prostate biopsy-positive group versus controls. We present here preliminary evidence showing that urine samples spiked with sarcosine/alanine can be partially resolved in 3 min via tandem differential mobility analysis-mass spectrometry (DMA-MS). Based on the calibration curves obtained for two mobility peaks, we finally estimate their concentration ratio in urine.

Graphical AbstractWe explore here the capabilities of an IMS (DMA)-MS system to resolve isomers L-alanine and sarcosine in urine.Figure optionsDownload high-quality image (186 K)Download as PowerPoint slide