HRMS Profiling: (Instrument: Orbitrap Elite )
To evaluate the fluctuations in metabolome level and to identify differentially expressed metabolic features between samples. It only consists of full range (usually 80-1200) MS1 scans for detecting and quantify metabolic features in samples. The formula of metabolic features can be determined by accurate mass and relative isotopic ratio (RIA) in MS1 scans. Generally, thousands of metabolic features can be obtained depending on the samples and experimental setup.
HRMS plus Targeted HRMS/MS Metabolite Identification and Quantification: (Instrument: Orbitrap Elite and Orbitrap Fusion Lumos)
HRMS Profiling plus Parallel Low Res. Targeted MS/MS for Markers: (Instrument: Orbitrap Elite)
HRMS Profiling plus PRM of Metabolite Markers: (Instrument: Orbitrap Fusion Lumos)
To obtain the HRMS metabolome profile with the specified metabolites accurately identified and quantified using HR- or LR- MS/MS. It consists of full range (usually 80-1200) MS1 scans and continuous acquisition MS2 scans for specified metabolites as biological markers or indicators. Compared to the quantification using MS1 spectra, the use of MS2 scans for specified or targeted metabolites provides a better sensitivity and accuracy. To get the absolute quantification values of specified metabolites, the isotope-labeling standard can be spiked in samples and analyzed with PRM mode. The MS1 scans can additionally be used to detect and quantify other metabolic features. Low Res. Targeted MS/MS can have a better sensitivity than the use of HRMS/MS in most cases.
HRMS/MS for Specific Metabolite: (Instrument: Orbitrap Elite)
To obtain High or Ultrahigh resolution and accurate MS and MS/MS spectra of specific metabolite for structural verification. Optimization of MS/MS collision energy and LC separation power is required in this service mode to ensure good coverage of structural information and minimal interference from sample matrix.
Data-dependent MS2-MSn Metabolomics Analysis: (Instrument: Orbitrap Fusion Lumos)
The most widely used method aiming for metabolomics profiling. It consists of full range (usually 80-1200) MS1 scans and data-dependent MS2-MSn scans. The MS1 scans are used to detect and quantify metabolic features and the MS2-MSn scans are used for metabolite identification via spectra library searching. Generally, thousands of metabolic features and hundreds to one thousand metabolites can be confidently identified depending on the experimental design, sample properties and the performance of MS platforms.
ID of Novel Metabolite Identification using HRMS and MSn: (Instrument: Orbitrap Fusion Lumos)
Aim for the identification of novel metabolites. It consists of ultra-high resolution of MS1 scans and mutliple MSn for a or few specified metabolites. The MS1 scans can determine the exact mass (sub-ppm mass error) and isotopic pattern for elemental composition and the multistage MSn spectra can provide more in-depth structural information. Users should capable to intemperate the MS spectrum based on their own domain knowledge, developed software or biological hypothesis (e.g. To verify or deduce a proposed metabolic pathway or reaction or ID of the metabolite by specific drug or environmental/chemical exposure).