Today, high-resolution mass spectrometry (HRMS: Q-TOF-MS, Orbitrap-MS) shows sensitive and reliable quantifications of a large variety of compounds while acquiring in high-resolution full-scan mode. Interestingly, HRMS shows equal quantitative performance than triple-quadrupole-MS (QQQ-MS), which is the MS technology traditionally used for quantification. But, in contrast to QQQ-MS that performs “narrow-minded” ion transitions (targeted prior determination), analysis using HRMS can record HR-full scan that detects virtually all ions (e.g., from m/z = 80 to 1000) and gives a global picture of what is in the biological sample (diagnostic screening). This is more and more seen as a key advantage because on top of targeted and quantitative analyses, many other routine or research determinations can be performed such as qualitative (identification), simultaneous quantitative/qualitative (quan/qual), and omics (untargeted) assays. The high versatility and performance of most actual HRMS instruments placed them as new gold standards in LC-MS analysis. Indeed, only HRMS can answer new analytical requests from systems biology and personalized medicine requesting more holistic approaches with untargeted analyses (e.g., proteomics and metabolomics). In the light of the new HRMS-based paradigm, concrete examples revealing quantitative, qualitative, simultaneous quan/qual, and omics capabilities of HRMS in the context of routine and research analyses will be given.
Part of the book: Recent Advances in Analytical Chemistry