Micro extraction to quantitate spermidine and spermine in human urine and blood by matrix-assisted laser desorption ionization time-of-flight mass spectrometry

Spermidine and its derivative, spermine, are basic compounds with unique roles in physiological function. This study used matrix-assisted laser desorption/ionization time-of-flight (MALDI-TOF) mass spectrometry (MS) to monitor these analytes in human urine and blood. The MALDI-TOF MS is also suitable when a high-throughput analytical method is required. Unlike liquid chromatography (LC)-MS, MALDI-TOF MS does not require a mobile phase in sample separation and generates very little organic waste. Micro liquid-liquid extraction was also performed to minimize the use of organic solvents in this study. After alkalization step, biosamples were prepared by adding a small volume (20 mu L) of organic solvent to concentrate, and purify the spermidine and spermine contained in the urine and blood samples. A suitable extraction protocol was developed after optimizing various conditions associated with extraction efficiency. The proposed method was then successfully used to monitor these compounds in human urine (mean value < 1 mu g/mL) and blood (mean value > 1 mu g/mL). (C) 2013 Elsevier B.V. All rights reserved.