Chromatographic peptide peak integration is used for quantitation with the stable isotope dilution method using heavy isotope-labeled peptides as internal standards, which are spiked into the samples during work-up.
Total energy expenditure (TEE) was measured in these participants using the doubly-labeled water method (Subar et al., 2003) using isotope measurement methods described by Schoeller et al. (Schoeller, 1988) and Coward and Cole Colee & Coward, 1992).
We first devised a combined flux profiling and metabolite profiling method using C isotope tracing from glucose.
Simulated recharge compared well with estimates obtained using isotope methods from previous studies and allowed us to identify specific annual signatures of this important process during the period of study (1997 2007).
This variation provides an opportunity using isotope methods to test whether there was evidence for structuring of daily activities (diet in this case) that might serve to reinforce this change in burial practice.
POPs were analyzed in 2 mL serum at the laboratory of the School of Environmental Science and Engineering, POSTECH (Pohang, Korea) using isotope dilution method with gas chromatography-high resolution mass spectrometry (GC-HRMS).
We present here an integrated quantification (InteQuan) method that better controls pre-analytical and analytical variability than the popular quantification method using stable isotope-labeled standard peptides (SISQuan).
In contrast, we used an LC-MS/MS method, thereby, for the first time, using isotope dilution internal standardization.
The team compared the results from this technique with a similar method using two different isotopes.
Chan et al. (2016) developed a novel method using gas chromatography, combustion, and isotope ratio mass spectrometry to determine compound-specific nitrogen isotope compositions with an achiral column, which was previously shown to offer high precision for nitrogen isotopic analysis.
