Automated library generation for untargeted metabolomics studies

A major limitation for untargeted metabolomics studies is the generation of a library or target component list from the deconvoluted mass spectral data files. In order to achieve this, a script was written to compile a library from the results output of SpectralWorks AnalyzerPro. A set of 24 plasma samples from pigs were extracted and analysed using an Agilent 5973 GC-MS single quadrupole instrument. Generation of a library from this data set initially yielded a library with 2146 components, which reduced to 660 components after manual quality control. The same samples using an in-house target component list of 350 compounds generates an average of only 102 matches that can be used for subsequent analysis. This represents an increase of nearly 650% using the automated library generation. The same samples were analysed by GCxGC-TOF-MS using a LECO Pegasus 4D. Automated library generation was performed using the LECO ChromaTOF software. Generation of a library from these samples yielded a library with 3689 components, which reduced to 963 components after manual quality control. The key limitation of this technique is the requirement to manually quality control the data set. To overcome this, the process has now been integrated into AnalyzerPro. Automated library generation is a relatively simple option for strengthening metabolomics data sets and taking better advantage of the data generated by mass spectral analysis