Influence of ionization source design on matrix effects during LC-ESI-MS/MS analysis.

Area of Science:

• Analytical Chemistry
• Biochemistry

Background:

• Glycerophosphocholines (GPChos) are common interferents in LC-MS/MS analysis of biological samples.
• Matrix effects, such as ion suppression or enhancement, are influenced by sample preparation and instrument design.

Purpose of the Study:

• To investigate the impact of different ionization source designs on matrix effects during LC-MS/MS analysis.
• To evaluate the role of GPChos in causing these matrix effects using acamprosate as a model analyte.

Main Methods:

• Analysis of acamprosate (ACM) in negative polarity using electrospray ionization.
• Comparison of Z-spray and orthogonal spray ion sources coupled with UPLC/HPLC.
• Identification of GPChos responsible for matrix effects via mass spectrometry.

Main Results:

• Significant ion suppression of ACM was observed with the Z-spray source.
• Minor ion enhancement of ACM was observed with the orthogonal spray source.
• Distinct GPChos (m/z 815.4 and m/z 759.0) were identified as the cause of matrix effects in each source.

Conclusions:

• Ionization source design critically influences matrix effects in LC-MS/MS.
• The developed approach can assess matrix effects in plasma samples for LC-MS/MS method validation.
• Understanding these effects is crucial for accurate drug and metabolite quantification in biological matrices.