base peak


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base peak

The ion in a mass spectrum with the highest measured abundance.
The relative abundance of the base peak ion is assigned a value of 100, and the abundances of all other ions plotted in that mass spectrum are normalised to that value. The y-axis in a mass spectrum is therefore given in terms of relative abundance.
References in periodicals archive ?
This applies to any SMN mutated site; when the percentage of variant base peak is similar to that of differential site on exon 7, it implies that the mutation is in SMN1 [Figure 6].
For peaks 19, 28, 41, and 42, the base peak [[M + H].sup.+] ion was observed in the MS spectra.
M = 110 is base peak. m/z PICS 67% interval 95% interval unc.
All the fragmentations of cellulose are present and the base peak of fragmentation appears at m/e 76 due to positive ion or free radical positive ion of CS2.
The base peak at m/z 545 corresponding to the loss of 30 u (methoxy group) from fragment ion at m/z 575 was indicative of the presence of a methyl group on the flavone moiety (chrysoeriol) in compound 5.
The mass spectra exhibited m/z 437 (M-45, 392, 1.0%) with a base peak at 148 for the fragment [C.sub.7][H.sub.3][N.sub.3]F.
The complex A showed base peak at m/z = 152 due to [C.sub.10][H.sub.17]N fragment ion and 4,4'-dimethoxy-2,2'-bipyridine ligand in the complex showed peak at m/z = 217 with relative intensity of 25%.
A third approach is to align the "Base Peak" chromatograms, as performed by SIEVE from Thermo Scientific, and a fourth approach is an alignment using MS/MS scan times (identified peptides), such as that found in IDEAL-Q [24].
Mass spectral data of (2) indicated that this compound was a nonadienol which readily dehydrated to give an ion at m/e 122 and other prominent ions at m/e 67, 93, 79, 55 and 41; mass spectrum of (3) resembles a sesquiterpene with molecular ion of m/z 204, with characteristic ions at 49 (base peak), 84, 105, 133, 147, 161, 175 and 189; the mass spectrum of peak (7) showed characteristic ions at 49 (base peak), 93, 107, 119, 135, 161, 189 and molecular ion m/z 204; peak (8) displayed a molecular ion of m/z 204, with characteristic ions at 41, 91, 197, 135 (bases peak); and peak (9) had a molecular ion of m/z 204, with characteristic ions at 49 (base peak), 84, 105, 133, 147, 161, 175 and 189.
The mass spectral data recorded an odd number base peak at 163 M/Z for a compound whose molecular weight was observed at 194 M/Z.
One of the resulting peaks is a hydroxylation metabolite at 603.2805 m/z that elutes after 8.45 minutes and has an intensity that is less than 15% relative to the base peak in the same spectrum.