Meaning
Mass spectrometry signal attenuation caused by co-eluting matrix components reduces target analyte ion formation efficiency in electrospray ionization sources. Ionization suppression occurs when non-volatile salts, surfactants, or high-concentration polymer additives compete for available droplet surface charge during aerosol evaporation. In LC-MS analysis of plastic extracts, this interference underreports true concentration values of slip agents, light stabilizers, or residual monomers.
Quantitative accuracy fails when matrix components alter spray droplet surface tension or ion evaporation rates without detection.
Matrix Effect
Co-eluting compounds disrupt spray droplet charging mechanisms, preventing target analyte ions from entering the gas phase. Non-volatile polymer oligomers coat electrospray capillary tips, destabilizing the Taylor cone geometry. Post-column infusion tests map retention time regions suffering from signal loss.
Source Geometry
Nano-electrospray designs minimize droplet size distributions, reducing matrix interference compared to high-flow conventional sources. Heating gas flow rates and capillary voltage settings shift desolvation efficiency. Heated electrospray interfaces evaporate solvent faster, mitigating signal loss from non-volatile salts.
Mitigation Protocol
Chromatographic separation adjustments push target analyte peaks away from matrix solvent fronts and polymer oligomer tailing zones. Stable isotope-labeled internal standards track signal suppression, adjusting calculated concentrations automatically. Solid phase extraction cleanup removes interfering additives prior to LC-MS injection.
