K4[Fe(CN)6]/Glycerol—A New Liquid Matrix System for Matrix-assisted Laser Desorption/Ionization Mass Spectrometry of Hydrophobic Compounds

✍ Scribed by Peter Zöllner; Erich R. Schmid; Günter Allmaier

• Publisher: John Wiley and Sons
• Year: 1996
• Tongue: English
• Weight: 395 KB
• Volume: 10
• Category: Article
• ISSN: 0951-4198
• DOI: 10.1002/(sici)1097-0231(19960731)10:10<1278::aid-rcm661>3.0.co;2-l

✦ Synopsis

Since the introduction of MALDI mass spectrometry, only a few liquid matrix systems have been proposed. This paper reports a new liquid matrix system consisting of glycerol and K,[Fe(CN),]. With this binary system, best results are achieved for hydrophobic compounds like triacylglycerols, galactosyl diacylglycerols, phosphati- dylcholines, phosphatidylethanolamines, ceramides and several chloroform soluble, synthetic polymers. Only amounts of analyte in the femtomol range have been required to obtain good results with satisfactory mass resolution, mass accuracy and excellent shot-to-shot reproducibility. In all cases, only potassium adducts are formed. No protonated molecular ions could be detected. Potassium adducts of small peptides (up to approx. 3000 Da) and carbohydrates can also be generated with this matrix system but with lower sensitivity than in the case of hydrophobic compounds (picomol to nanomol range). Additionally, sample preparation in the case of hydrophilic compounds is critical and hard to reproduce. This is presumably caused by the destruction of the thin UV absorbing matrix layer by aqueous sample solutions.