In addition, the multiple reaction monitoring mode in GC/MS/MS is much more selective for PCBs than the more commonly used electron capture detection.
The quantification of the different DON molecules were made with standard molecules injected at different concentration using the MS/MS MRM (multiple reaction monitoring) mode in order to establish standard curves for each molecules.
After identification of metabolites in the scan mode using the NIST data bank, quantification of labeling enrichment was done in SIM (single ion monitoring) mode in two technical replicates using the following unique fragments (m/z) containing the complete carbon skeleton of metabolites: pyruvate 174, lactate 261, alanine 260, glycine 246, serine 390, aspartate 418, glutamate 432, glutamine 431.
Liquid chromatography was performed at 30°C using an Acquity UPLC BEH C18, 1.7 μm, 2.1 × 100 mm column (Waters, Milford, MA), and the Micromass Quattro Premier XE Tandem Mass Spectrometer (Waters) was used in the multiple reaction monitoring mode in the electrospray ionization positive mode.
The study of small-scale ionospheric irregularities at high latitudes of the Russian Federation in a monitoring mode began in December 2012 when first Russian SuperDARN radar near Yekaterinburg (EKB radar, 56N, 58E) had started operations.
Engineering of optical captors allows facile and reliable signaling in continuous monitoring modes, and enables simple and high-speed removal of toxic chromium (VI) ions.
Data acquired in multiple reaction monitoring mode are shown in Figure 1A, which shows traces produced by synthetic 2b as well as isolates from control histones (not treated with 3,5-DMAP) and histones from treated cells.
The selected reaction monitoring mode was used in this study and therefore made it more specific and sensitive for quantitative analysis (Fig. 3).
Direct determination of multiple sugars and sugar alcohols was carried out using a mass spectrometric detector operated in a multiple reaction monitoring mode, providing detection limits in the range between 0.1 and 20 ng/mL and good analytical characteristics of the method without derivatization.
Ions were generated by ESI source and analyzed by multiple reaction monitoring mode (basis for quantification) in the Agilent 6410 QqQ analyzer.
