Does the Mass Spectrometer Define the Marker? A Comparison of Global Metabolite Profiling Data Generated Simultaneously via UPLC-MS on Two Different Mass Spectrometers

摘要

By coupling a single UPLC separation to two differentntypes of mass spectrometer an unbiased comparison ofnthe metabolite profiles produced by each instrument forna set of rat urine samples was obtained. The flow fromnthe UPLC column was split equally and both streams ofneluent were simultaneously directed to the inlets of thentwo mass spectrometers. Mass spectrometry on the eluentnwas undertaken using a triple quadrupole linear ion trapnand a hybrid quadrupole time-of-flight mass spectrometernusing both positive and negative ESI. Data from both massnspectrometers were subjected to multivariate statisticalnanalysis, after applying the same data extraction software,nand showed the same general pattern of correlationnbetween the samples using both unsupervised and supervisednmethods of statistical analysis. Based on orthogonalnpartial least-squares discriminant analysis modelsna number of ions were recognized as “responsible”nfor the separation of the animal groups. From the peaksndetected, and denoted as significant by the statisticalnanalysis a number of ions were found to be unique to onendata set or the other, a result which may have consequencesnfor biomarker discovery and interlaboratoryncomparisons. The software package used for data analysisnalso had an effect on the outcome of the statisticalnanalysis.