Related Experiment Videos
Electrospray ionization suppression, a physical or a chemical phenomenon?
Francis Beaudry1, Pascal Vachon
1Faculty of Veterinary Medicine, Department of Veterinary Biomedicine, University of Montreal, St-Hyacinthe, Canada. francis.beaudry@umontreal.ca
Biomedical Chromatography : BMC
|August 10, 2005
Summary
Ion suppression in High-Performance Liquid Chromatography-Mass Spectrometry (HPLC-MS) is influenced by increased electrical conductivity in biological samples. This conductivity affects electrospray behavior and impacts quantitative analysis accuracy.
Area of Science:
- Analytical Chemistry
- Biochemistry
- Mass Spectrometry
Background:
- High-Performance Liquid Chromatography with tandem Mass Spectrometry (HPLC-MS) is a crucial technique for analyzing drugs, metabolites, biomarkers, and proteins.
- Ion suppression is a significant challenge affecting the quantitative accuracy of HPLC-MS methods in bioanalytical laboratories.
Purpose of the Study:
- To investigate the relationship between observed current and signal intensity during ion suppression in HPLC-MS.
- To understand how variations in observed current affect quantitative performance when analyzing biological samples.
Main Methods:
- Analysis of biological samples using HPLC-MS.
- Measurement of observed current (I) and its correlation with signal intensity.
- Evaluation of current variations during ion suppression events.
Main Results:
- An increase in observed current (I) during ion suppression indicates a significant rise in liquid conductivity.
- While other chemicals can compete for protons, increased conductivity is a key factor during signal suppression.
- Salts and charged species alter droplet conductivity and surface tension, disrupting electrospray stability.
Conclusions:
- Increased electrical conductivity, driven by salts and charged species in biological samples, plays a critical role in ion suppression during HPLC-MS.
- Understanding these conductivity changes is essential for mitigating erratic electrospray behavior and improving quantitative accuracy in bioanalysis.