‘All‐in‐One’ analysis for metabolite identification using liquid chromatography/hybrid quadrupole time‐of‐flight mass spectrometry with collision energy switching

Abstract

The removal of bottlenecks in discovery stage metabolite identification studies is an ongoing challenge for the pharmaceutical industry. We describe the use of an 'All-in-One' approach to metabolite characterization that leverages the fast scanning and high mass accuracy of hybrid quadrupole time-of-flight mass spectrometry (QqToFMS) instruments. Full-scan MS and MS/MS data is acquired using collision energy switching without the preselection, either manually or in a data-dependent manner, of precursor ions. The acquisition of 'clean' MS/MS data is assisted by the use of ultrahigh-performance chromatography. Data acquired using this method can then be mined post-acquisition in a number of ways. These include using narrow window extracted ion chromatograms (nwXICs) for expected biotransformations, XICs for the product ions of the parent compound and/or expected modification of these product ions, and neutral loss chromatograms. This approach has the potential to be truly comprehensive for the determination of in vitro biotransformations in a drug discovery environment.

In vivo D2O labeling to quantify static and dynamic changes in cholesterol and cholesterol esters by high resolution LC/MS

“…The dopant used for the APPI experiments was acetone (Fisher Scientifi c, Pittsburgh, PA), which was infused at a continuous fl ow rate of 100 l/min post column. The desolvation source conditions for APPI were as follows: for the desolvation gas, 900 l/hr was used and the desolvation temperature was kept at 600 C. Data were acquired over the mass range of 50-1200 Da for both MS and MS E modes (40)(41)(42)(43). The mass spectral resolution was set to 25K full width half mass (FWHM) and typical mass accuracies were in the order of 0-2 ppm.…”

High-Resolution Mass Spectrometry Elucidates Metabonate (False Metabolite) Formation from Alkylamine Drugs during In Vitro Metabolite Profiling

“…Time-of-flight (ToF) mass spectrometers are high-resolution instruments with fast cycle times, making them compatible with the higher-resolution ultra-highpressure liquid chromatography (UHPLC) systems currently available (Castro-Perez et al, 2005). The combination of UHPLC with ToF MS provides a robust platform for rapid profiling and characterization of metabolites formed from new drugs and enables implementation of generic analytical workflows, such as elevated energy MS (MS E ), comprising simultaneous acquisition of precursor (m/z values corresponding to intact metabolites for biotransformation assignment) and product ion data (tandem mass spectral fragmentation data for structural elucidation of metabolites) by generating full-scan mass spectral data that are subsequently deconvoluted and mined by software strategies capitalizing on the high information content associated with accurate mass (Wrona et al, 2005;Bateman et al, 2007). Such generic workflows, also known as qualitative/quantitative analysis, yield complex data sets that can be mined in different ways to obtain different types of information.…”

A data-independent acquisition workflow for qualitative screening of new psychoactive substances in biological samples

“…Data-dependent acquisition generates MS/MS spectra for pre-selected compounds and may miss potential compounds of interest, particularly co-eluting compounds [10]. Since with a data-independent method no compounds are pre-selected, all compounds are subject to collision induced dissociation including co-eluting compounds.…”

“…In data-independent acquisition mode, all ions are fragmented without a specific isolation of a precursor ion in the first mass analyzer [8][9][10]. This mode is also known as MS E , All Ions MS/MS or all-ion fragmentation (depending on the manufacturer).…”