Reduction in Matrix-Related Signal Suppression Effects in Electrospray Ionization Mass Spectrometry Using On-Line Two-Dimensional Liquid Chromatography

The effect of liquid chromatographic separation on matrix-related signal suppression in electrospray ionization mass spectrometry (LC-ESI-MS) was investigated. A method incorporating on-line two-dimensional liquid chromatography mass spectrometry (LC/LCMS) was developed to compensate for matrix effects and signal suppression in qualitative and quantitative analysis. The LC/LC-MS(MS) approach was successfully applied for singlecomponent and multicomponent analysis in a variety of complex matrixes. It was demonstrated that matrix-related signal suppression could be induced solely by (i) column overload, (ii) matrix component-analyte coelution, or a combination of each. Application of on-line orthogonal LC/LC separations can be effective in reducing both causes of matrixrelated signal suppression effects i.e., column overload and matrix-analyte coelution for a variety of LCn/MSn applications.