electrospray ionization
Also written as: ESI — Electrospray Ionization
Mass spectrometry ionization technique used to convert liquid samples into gas-phase ions for metabolite analysis in newborn screening.
Full Definition
Electrospray ionization (ESI) is a soft ionization technique used in mass spectrometry to produce gas-phase ions from liquid samples without excessive fragmentation. In newborn screening applications, ESI is the primary ionization method for tandem mass spectrometry analysis of amino acids, acylcarnitines, and other metabolites extracted from dried blood spots. The technique works by applying a high voltage to a liquid sample as it exits a capillary, creating a fine spray of highly charged droplets that undergo solvent evaporation and ion desorption. ESI's ability to produce multiply charged ions and preserve molecular integrity makes it ideal for analyzing the diverse range of polar metabolites targeted in newborn screening panels.
Usage
Usage note: Typically abbreviated as ESI in mass spectrometry contexts; hyphenate when used as compound modifier.
In Context
- "Electrospray ionization parameters were optimized for maximum sensitivity of acylcarnitine detection." — Method validation report
- "The laboratory troubleshooted electrospray ionization source contamination affecting peak intensities." — Maintenance log