Chromatogram annotation

Figure 5.28 LC-electrospray-MS total ion chromatogram of sulfated oligosaccharides from mucins purified from the porcine large intestine, where the annotations indicate the molecular ions observed from each component. Reprinted with permission from Thoms-son, K. A., Karlsson, H. and Hansson, G. C., Anal. Chem., 72, 4543-4549 (2000). Copyright (2000) American Chemical Society.

Figure 14 shows a Waters Millennium screen with multiple windows displaying a contour map, a chromatogram at a specified wavelength and the spectrum of the active ingredient peak in the test sample. Most software also allow automated spectral annotations of peak... 

Figure 6.3. Metabolite profile of razaxaban (C24H2oNg02F4) in dog bile (a) base peak chromatogram of unprocessed LC-MS data (b) base peak chromatogram of processed LC-MS data (c) corresponding radioactivity chromatogram. The arrows annotate the retention time of the peak shown in Fig. 6.2. Bile was collected from dogs orally administered with 14C-labeled razaxaban (20 mg/kg). HPLC solvents were 10mM NH4HC03 (pH 9.0) and acetonitrile. A portion of the HPLC effluent was collected in 15-s fractions for the radioactivity chromatogram. Another portion of the HPLC effluent was directed to a Q-TOF Ultima mass spectrometer.

The other piece of mandatory equipment that has changed recently is the data acquisition computer. Previously, every inexpensive HPLC had to have a strip chart recorder. The price differential between a computer-generated annotated chromatogram and a strip chart has dropped to the point that it doesn t make sense not to have that capability in the lab. You may only integrate 1 run out of 10, but when you need it, the capability will be there. Try and avoid a computer system using a thermal or inkjet printer. The paper does not store well for a permanent record. Often, it will be necessary to photocopy the keeper chromatograms for further reference and archival storage. 

Another, more accurate method is to copy the chromatogram, cut out the peaks, and weigh them. Of course, if you have an integrator or a data processing computer system, it will do the job for you. They can usually be set to do either peak heights or areas. They also can be calibrated for standard runs and will calculate actual amounts relative to these earlier runs. Some also can be calibrated with compound names related to peak retentions to provide annotated outputs. 

Purge line A with water and line B with MeOH. Dial-a-mix 70% MeOH and equilibrate the C18 column at l.OmL/min. When stable, inject 15pL of the seven-component test mixture and annotate the chromatogram s start. Run an isocratic chromatogram. 

Inject 15j L of the seven-component standards test mixture. Annotate and run an isocratic chromatogram. 

Put acetonitrile in the B reservoir. Purge the pump inlet line with acetonitrile. Dial-a-mix 60% acetonitrile/water. Reconnect the C18 column at O.lmL/min. Increase the flow to l.OmL/min and equilibrate the column. Inject 15 pL of the seven-component test mixture. Annotate and run the chromatogram. 

Figure 10.4 Representative HPLC chromatograms (a) excipient placebo for the high dose active IR portion of the bilayer tablet (b) excipient placebo for the low-dose active sustained release portion of the bilayer tablet (c) Amicon Ultra-4 filtered fixed combination tablet sample. Annotation 1 = low-dose active ingredient 2 = high-dose active ingredient = pregelatinized starch-related peak = HPMC-related peak = filter-related peaks.

Figure 20.4 Base-peak chromatogram of RNase B oligosaccharide alditols, acquired using a graphitized carbon column in LC-MS. Peak annotation (a)...

Fig. 1. HPLC of tryptic digest of human globins (a and P)from hemoglobin treated in vitro with [8-14C] styrene-7,8-oxide (a) chromatogram numbers refer to fractions, (b) radiogram annotation refers to tryptic peptide.

Figure 4.10. Waters EmPower screen showing a contour map, a chromatogram at 270nm showing the separation of nitrobenzene and propylparaben. Spectra of these two components are shown in the right-hand panel annotated with their respective maximum absorbance wavelengths.

The stationary phase is of a functionalised silica-type, as indicated by different annotations on the base of the chromatogram. 

Fig. 7. Whole oil gas chromatograms of (A) a saturated low gravity oil and (B) an undersaturated high gravity oil, each representing oil end-members annotated in Figure 6. API gravity of the saturated sample has been corrected for 5.5% oil-based mud contamination which is also responsible for elevated amounts of nCii- C,g. The gas chromatogram shown in (C) shows the drilling mud additive used in the exploration and appraisal wells.

The C-terminal sequence of P40 was confirmed by sequencing the C-terminal peptide identified from the peptide map the peak annotated LI8 on the chromatogram corresponds to the C-terminus amino acids 337-344 (measured mass 870,61 Da theoretical mass 870,96 Da). The sequence deduced from the sequencing analysis, EVVTQPQA, was in accordance with the theoretical amino acid sequence. 

Calculation of the RIs is required for the correct annotation of peaks in a GC/MS chromatogram. In every GC/MS analysis in which retention time standards are added to the analyzed samples, correction of retention time values according to the values obtained for standards (i.e., FAME) should be performed. On this basis, RI values for consecutive compounds in the time window between two standards may be calculated. 

Supporting documentation produced by lab equipment should usually be included in the documentation. Electronic images or scanned images may be uploaded to the wiki. Documents that are not uploaded due to space limitations should be filed carefully and cross-referenced in the wiki. Chromatograms may be held in binders, for example. Attached documentation should be annotated so that it is clearly related to the information in the wiki. For example, gel lanes and any bands that have been cut out should be marked. Electronic copies should be stored, and the file name and computer and folder (or directory) should be marked in the wiki. 

Figure 1 The electron ionization total ion current chromatogram for the trimethylsilyl derivatives of the organic acids extracted from the urine of a patient with an inherited error of methylmalonyl-CoA mutase. The major acidic component is methylmalonic acid. The annotated peaks are identified in Table 1.

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