Phosphoinositide Analysis by Liquid ChromatographyMass Spectrometry

The phosphoinositides are a highly dynamic group of molecules implicated in many cellular control processes; however, the analysis of many of these structures has proven very difficult and time-consuming, with limited sensitivity and/or discrimination. Recent developments in LCMS now provide the prospect of routine structural and quantitative analysis of all the known phosphoinositides (and possibly some as yet unidentified structures) at high sensitivity in any biological sample. The procedures described here give very high extraction recovery from a variety of biological matrices and enable chromatographic resolution of most phosphoinositides as their native structures. When coupled with the accurate mass and fragmentation capabilities of an MS, full structural and isomeric identification can be achieved.