Matriksiefektit

Matriksiefektit refers to phenomena observed in mass spectrometry where the ionization or detection of one analyte is influenced by the presence of other substances in the sample. This interference can lead to inaccurate quantitation or even the suppression or enhancement of the signal from the target analyte.

There are several types of matrix effects. Ion suppression occurs when the co-eluting matrix components reduce the ionization efficiency of the analyte, resulting in a lower signal. Conversely, ion enhancement happens when matrix components increase the analyte's ionization efficiency, leading to an artificially higher signal. These effects are particularly common in complex biological matrices like blood, plasma, urine, and tissue samples, as well as in environmental and food samples.

The severity of matrix effects depends on various factors, including the ionization technique used, the specific matrix components present, and the sample preparation method. Techniques like electrospray ionization (ESI) are known to be more susceptible to matrix effects than others, such as matrix-assisted laser desorption/ionization (MALDI).

To mitigate matrix effects, several strategies can be employed. Thorough sample cleanup and purification, such as solid-phase extraction (SPE) or liquid-liquid extraction (LLE), can remove interfering substances. Another common approach is the use of internal standards, particularly stable isotope-labeled internal standards, which are chemically similar to the analyte and undergo similar ionization and ionization suppression or enhancement. Matrix-matched calibration, where calibration standards are prepared in a matrix similar to the sample, is also an effective method. Understanding and addressing matrix effects is crucial for obtaining reliable and accurate results in quantitative mass spectrometry.