Meaning
Signal reduction occurring during ionization due to the presence of co-eluting compounds represents a major challenge in high-performance liquid chromatography analysis. In the detection of polymer additives and non-intentionally added substances, mass spectrometry matrix suppression occurs when non-target compounds outcompete target analytes for charge or surface spots on droplets during electrospray ionization. The phenomenon leads to underestimating the concentration of plasticizers and flame retardants in the sample.
The effect is resolved when the interfering matrix components are fully separated from the analytes of interest.
Interference Mechanism
High concentrations of non-volatile species can prevent the evaporation of aerosol droplets in the ionization chamber. This limits the transfer of charge to the target molecules. Surfactants and oligomers from the polymer are common sources of this signal loss.
Analytical Impact
Precision and accuracy are compromised when the signal fluctuates due to matrix variations. Calibrations can become unreliable if the standard solutions do not match the sample matrix. This makes quantitative verification of additive levels difficult to reproduce.
Mitigation Strategy
Sample preparation must include extraction or clean-up steps to remove the polymer matrix. Diluting the sample before injection can also minimize the suppression effect. Using internal standards compensates for any remaining signal loss.
