Quantitation of Inositol Phosphates by HPLC-ESI-MS
The coupling of anion exchange high-pressure liquid chromatography (HPLC) with electrospray ionization mass spectrometry (ESI-MS) allows for the simultaneous detection of the six forms of inositol phosphate (InsP). Here we describe a rapid quantitative analysis of InsPs by HPLC-ESI-MS, which can be applied to a wide array of sample types. With this method, InsPs could be separated and detected within 20 min of sample injection. The detection limit was as low as 25 pmol (i.e., ca. 2 nmol/g sample) for each type of InsP, which is particularly important for analytes that are often present at low abundance in nature.
Key wordsInositol phosphate Phytic acid HPLC Ion-exchange HPLC HPLC-ESI-MS
Financial supports for this research by The Graduate School of UGA and the Almond Board of California are gratefully acknowledged. Use of the Proteomics and Mass Spectrometry (PAMS) core facility with the assistance of Dr. Kevin D. Clark in UGA’s Department of Chemistry, Athens, GA, is greatly appreciated.