Targeted lipidomics: Analytical strategies for fatty amides.

摘要

There are many significant compounds whose resting levels in biological systems are at nanomolar concentrations or below. In order to more effectively study these compounds work is being done to develop a completely automated system on a microchip. Several steps will be taken to start setting up this system because, at these low concentrations, detection is problematic for many current methods of analysis. First, develop a high performance liquid chromatography with mass spectrometry detection (HPLC/MS) method using atmospheric pressure chemical ionization (APCI) to detect primary fatty acid amides (PFAMs), one of the lipid classes of interest. Additives such as formic acid will be added to the mobile phase in an HPLC/MS method in order to increase the analyte signal and lower detection limits. Second, develop a LC method to replace the solid phase extraction (SPE) method that uses a gradient elution instead of the step elution currently done. The LC method would allow for analysis with electrospray mass spectrometry (ESI-MS) in order monitor the separation between the "polar" neutral lipid classes. Third, develop a method using capillary electrochromatography (CEC) to separate the fatty amines that have been derivatized for fluorescence detection on a microchip packed with a C18 chromatographic stationary phase.