Chromatogram extracted ion

FIGURE 5.4 Chromatograms of 2DLC (affinity/SEC/MS). Bottom trace is affinity separation with UV detection and 2 min fraction specified. Middle trace is MS total ion chromatogram showing protein elution and salts diverted to waste. Top trace in MS extracted ion chromatogram of protein of interest. 

Figure 18 Positive electrospray extracted ion chromatogram of 1 ppm derivatised semicarbazide in water (scan 200-300 m/z).

Figure 9.7 Separation and detection of intermediates of the mevalonate-independent pathway of isoprenoid biosynthesis by LC-MS extracted ion chromatograms at (A) m/z 213 (1-deoxy-D-xylulose 5-phosphate), (B) m/z 215 (2-C-methyl-D-erythritol 4-phosphate), (C) m/z 520 (4-(cytidine 5 -diphospho)-2-C-methyl-D-erythritol), (D) m/z 600 (2-...

Figure 7.13 illustrates the utility of mass defect filtering (also known as exact mass filtering) and UPLC. It shows results of UPLC/MS assay of a bile sample containing buspirone and its metabolites.184 The top trace shows the (unfiltered) TIC for the sample the middle trace is the result of an exact mass filter the bottom trace is an extracted ion chromatogram for the M+16 or hydroxylated metabolites based on their exact masses. It is readily apparent that this new software tool may be very helpful for metabolite identification studies. 

FIGURE 11.5 Extracted ion chromatogram of patient sample at typical low level. (Source Zahlsen, K. et al. LCGCN Amer. 23, 390, 2005. With permission.)... 

Extracted Ion Chromatogram A chromatogram created by plotting the intensity of the signal observed at a chosen m/z value or series of values in a series of mass spectra recorded as a function of retention time. See also related entry on total ion current chromatogram. 

Fig. 2.6.1. RP-LC-ESI-MS analysis of flocculation sludge from a Barcelona drinking water treatment plant. Column Cig LiChrolute 250 X 4.6 mm, 5 pm, gradient elution with ACN-water. Upper trace total ion current (TIC), lower traces extracted ion chromatograms for NPEOs, raE0 = 1-5. Inset ESI mass spectrum of NPEO oligomeric mixture.

Fig. 2.12.16. Extracted ion chromatograms (C12 homologue m z = 304, C14 homologue m/z — 332, C1B homologue mlz = 360, and Cig homologue mJz — 388) from a sediment sample extracted with ASE and analysed by SPE-LC-ESI-MS with positive ion mode of operation under full-scan conditions. Peak numbers 1 = C12BAC, 2 = C14BAC, 3 = C16BAC, 4 = C18BAC [41].

Fig. 5.1.9. (—)-LC-ESI-MS extracted ion chromatograms of C6-SPC (m/z 271 left-hand side) and Cg-SPC (m/z 299, right-hand side) from samples of FBBR taken after 8, 11, 18 and 26 days after spiking of Ci2-LAS. Assignment of the individual recalcitrant species according to order of elution and formation (a-e). Modified from Ref. [34].

Fig. 5.1.12. ( — )-LC-ESI-MS extracted ion chromatograms of C7-SPC (m/z 285) from (A) an enriched river water sample, and (B) an FBBR sample taken 20 days (constant concentrations) after spiking with commercial LAS. The individual isomers (a-f) are...

Fig. 6.3.2. (— )-LC-ESI-MS extracted ion chromatogram of C7-SPC (mlz 285) in samples from (A) Rio Macacu, Brazil, (B) river Rhine, Germany, and (C) Baia de Guanabara, Brazil. Values in parentheses indicate relative peak area (a + b + c = 100%) (from...

Additional benefits of GCxGC-TOFMS include the generation of extracted ion chromatograms (EICs) postanalysis. This is particularly useful for group type analysis, or simplifying the identification of target analytes. In both cases, specific ions... 

FIGURE I A reconstructed extracted ion chromatogram of nicotinic acid and its six metabolites under HILIC conditions. Column Hypersil silica (4.6 X 50 mm) at a flow rate of 4 mL/min. Mobile phase A is water, mobile phase B is acetonitrile, both containing 1% formic acid. Gradient is 0.01-0.25 min 90% B to 65% B 0.25-0.90 min 65% B to 50% B. NA nicotinic acid NAM nicotinamide NUA nicotinuric acid 2-PY l-methyl-2-pyridone-5-carboxamide l-MNAM I-methyl-nicotinamide NAMO nicotinamide-N-oxide 4-PY l-methyl-4-pyridone-5-carboxamide. (Reprinted with permission from Reference 20.)... 

Fig. 3.5 (A) Extracted ion chromatogram (XIC) of m/z 515.2 (M+H)+ from an ALIS experiment with DHFR and NCL127A443. (B) XIC of m/z 515.2 from control experiment (no library). (C) Mass spectrum of the region near m/z 515.2 underlying the XIC peak in A. Reprinted from [40] with permission from Elsevier.

Figure 5.7 demonstrates the implementation of the assay and shows the readout in the MS that was obtained for injections of the AChE inhibitor galanthamine at 0, 1, and 10 pM. Figure 5.7a shows the extracted ion chromatogram of galanthamine, Fig. 5.7b shows the extracted ion chromatogram of HMQI (prod-... 

Fig. 5.13 On-line continuous-flow, multi-protein biochemical assay. MS instrument Q-ToF2 (Waters) equipped with a Waters Z-spray electrospray (ESI) source. Extracted-ion chromatograms of (a) digoxigenin (m/z 391.5), (b) biotin (m/z 245.0), (c) fluorescein-biotin/streptavidin (m/z 390.0) assay and (d) digoxin/anti-digoxigenin m/z 798.5) assay. Triplicate injections were performed WITH blank (peaks 1-3), 1 pM digoxigenin (peaks 4-6) and 1 pmol biotin (peaks 7-9).

Fig. 3.1.7 Detection of HG by the GC-MS TIC method in the urine of patients with MCAD deficiency collected at different clinical statuses. A, left panel Organic acid profile of an acutely ill patient. The arrow indicates the portion of the chromatogram shown in the middle panel. Peak labeling 1 HG, 2 4-hydroxyphenylacetic acid. Right panel extracted ion chromatograms of the [M-15]+ ion of HG (m/z 230 red) and 4-hydroxyphenylacetic acid (m/z 281). Patient recovering from an acute episode. C Asymptomatic patient. The latter profile represents a situation where there is a high probability that HG may not be detected by a GC-MS TIC method...

True profile analysis requires scanning over the whole mass range for the acquisition of all data on excreted compounds. Quantitation has been more challenging on a quadrupole instrument because total ion current peaks are seldom a single component and extracted-ion chromatograms (EICs) when recovered from scanned data are of poor quality due to the lower sensitivity of scanning GC-MS. Thus, we developed profile analysis based on SIM of selected analytes but tried to ensure the components of every steroid class of interest were included. For ion traps the fundamental form of data collection (in non-MS/MS mode must be full -scans). Thus, the quantitative data produced are EICs obtained from scanned data. The EICs are of the same ions used for SIM in quadrupole instruments and the calibration external standards are the same. 

In Fig. 4.10, a total ion chromatogram (TIC) from a biological sample is compared with extracted ion chromatograms (XICs) for the analyte of interest (m/z 211.97)... 

Figure 4.10. Example of extracted ion chromatograms with different resolution extraction windows. The bottom trace represents the TIC. If we focus on compound D, it is apparent that as the extracted ion chromatogram window is tightened from 0.1 to 0.02 Da, A, B, and C (endogenous peaks) gradually disappear. Therefore, the high resolution of the TOF eliminates interferences and provides a chromatogram with better signal-to-noise ratio.

Exact mass filter exclusion based on the decimal places of a parent dmg, is a post processing filter which allows complete removal of unexpected entities (ions) which do not agree with the criteria preset by the user. Such a filter is fully adjustable once the samples have been processed. This process can dramatically reduce the number of ions in the analyte sample by filtering out the vast majority of matrix-related ions. This will also allow use of very low threshold values to detect low-level metabolites without having to go through the very tedious and long task of manual exclusion of false positives. Typically, extracted ion chromatogram windows of 0.1 mDa allow the... 

Kuehl, D., Gu, M., and Wang, Y. (2006). Comparing mass defect filtering and accurate mass profile extracted ion chromatogram (AMPXIC) for metabolism studies. In Proceedings of the 54th ASMS Conference on Mass Spectrometry and Allied Topics, Seattle, WA. 

Figure 9.1. Extracted ion chromatograms for m/z 311 (DL) and 327 (6-OH-DL, 3-OH-DL, N-OH-DL, and 1-pyridine-bi-oxide-DL) generated using a TSQ Quantum mass spectrometer (LC-APCI-MS).

Lew authors described antidepressant analysis in alternative specimens, such as hair or oral fluid. LC-CID-MS and MS/MS mass spectra libraries for identification of several drugs were employed by Muller et al. [32] for the detection of maprotiline, citalopram, and their desmethyl metabolites in authentic hair specimens extracted ions chromatograms were employed for subsequent antidepressant quantification. Also Klys et al. [33] applied LC-MS/MS to the analysis of blood, urine, and hair specimens in a fatal case due to clomipramine overdose in combination with alcohol. Blood clomipramine and norclomipramine concentrations explained the fatal outcome, and hair analysis confirmed that the deceased was on clomipramine treatment for, at least, 12 months prior to his death. With regard to oral fluid analysis, de Castro et al. [34] developed and validated a... 

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