440. spike recovery The amount of analyte that is measured upon analysis of a sample (e.g., matrix) to which a known amount of analyte has been added. Also see ‘Recovery’.
441. stability The chemical stability of an analyte in a given matrix under specific conditions for given time intervals.
442. stable-labeled isotope Analyte in which a few atoms are exchanged with heavy isotope counterparts, typically 2
H, 15 N or 13
C. It is commonly used as an
internal standard in LC–MS bioanalysis as it has very similar physical and chemical properties as the analyte and works well to compensate for the variability due to extraction, chromatography and mass spectrometry (MS) detection.
443. stable-labeled protein Full-length protein in which specific amino acids are exchanged with heavy isotope counterparts. It is used as an internal standard for LC–MS absolute quantification of protein(s) as it mimics the biochemical behavior of the protein analyte, thus correcting for variability occurring during sample preparation, sample digestion and LC–MS detection.
