Separation and quantification of choline and acetylcholine by thermospray liquid chromatography/mass spectrometry

The development of sensitive analytical techniques for use in the identification and qualification of molecules of biological origin remains a constant challenge. Often the compounds of interest are present in a complex mixture and require extensive sample preparation prior to analysis. Thermospray liquid chromatography/mass spectrometry (LC/MS) has been shown to be a method which allows for both separation of target molecules from complex mixtures and sensitive specific detection using a mass spectrometer. In this work thermospray LC/MS is used for the direct detection of intact, underivatized choline and acetylcholine from mouse brain homogenate. The results of our analysis corroborate previous analyses using a variety of indirect measurement techniques and thereby show that this simple direct analysis has wide potential applicability.