Peaks are numbered 1-7 and were shown to coelute
with (1) ursolic acid, (2) epicatechin, (3) caffeic acid, (4) rutin, (5) quercetin, (6) naringenin, and (7) kaempferol.
Extractables may appear as a distinct peak or may coelute
with the analyte of interest, thereby complicating quantiation.
Since [sup.13]C-containing peptides coelute
with peptides with natural isotopic distribution, both endogenously acetylated and [sup.13]C-acetylated peptides can be fragmented together using a slightly wider isolation window (3.5 m/z compared to 2.0 m/z) than that for standard analyses.
Glycated HbS fractions coelute
with [HbA.sub.2] on HPLC; as a result, the [HbA.sub.2] fraction is overestimated.
Thus, after verifying that FFA peaks did not coelute
with FAME, the procedure of Ichihara et al.
Combined with Deconvolution Reporting Software and databases, compounds can be detected even when they coelute
BDE-153, however, is not known to coelute
with other analytes in the method applied by Laboratory 2, and BDE-153 concentrations were almost 2-fold higher in December than in September for three family members (Table 1).
These two compounds were not observed in SRM 3083 by GC-ECD and did not coelute
with other PCB congeners present in SRM 3083 on a 5% phenyl methylpolysiloxane phase or a relatively non-polar phase (described above in Sec.
Solventless GC injections offer several advantages: methods are faster and less laborious, costs associated with purchasing solvents and disposing of used solvents is avoided, and peaks that may coelute
in the solvent front can be quantitated with a solventless injection.
The chromate, iodide, and chloride peaks were found to coelute
. However, the use of other wavelengths can spectrally resolve these three ions.
Some products may contain GOS disaccharides that coelute
with the lactose in the reference method, leading to an overestimation of lactose and consequently an underestimation of GOS.
In addition to the location and spectral deconvolution of coeluting peaks, minor components that coelute
with major peaks can be identified, and analytes that are too small to appear in the total ion chromatogram can be located.