isotope dilution mass spectrometry
Also written as: IDMS — Isotope Dilution Mass Spectrometry
Quantitative analytical technique using stable isotope-labeled internal standards for accurate metabolite measurement in newborn screening.
Full Definition
Isotope dilution mass spectrometry (IDMS) is a highly accurate quantitative analytical technique that uses stable isotope-labeled analogs of target compounds as internal standards. In newborn screening applications, IDMS involves adding known amounts of isotopically labeled amino acids, acylcarnitines, or other metabolites to dried blood spot extracts before analysis. The isotope-labeled internal standards undergo identical chemical and physical processes as the native analytes during sample preparation and analysis, but can be distinguished by mass spectrometry due to their different mass-to-charge ratios. This approach compensates for losses during sample preparation, matrix effects, and instrument variability, providing exceptional accuracy and precision essential for reliable diagnosis of metabolic disorders.
Usage
Usage note: Hyphenate when used as compound modifier; commonly abbreviated as IDMS in analytical chemistry contexts.
In Context
- "Isotope dilution mass spectrometry ensures accurate quantification despite matrix interference effects." — Analytical method description
- "The laboratory implemented isotope dilution mass spectrometry to improve measurement accuracy for critical analytes." — Quality improvement report