Critical factors determining the quantification capability of matrix-assisted laser desorption/ionization-time-of-flight mass spectrometry

Quantitative analysis with mass spectrometry (MS) is important but challenging. Matrix-assisted laser desorption/ionization (MALDi) coupled with time-of-flight (TOF) MS offers superior sensitivity, resolution and speed, but such techniques have numerous disadvantages that hinder quantitative analyses. This review summarizes essential obstacles to analyte quantification with MALDi-TOF MS, including the complex ionization mechanism of MALDi, sensitive characteristics of the applied electric fields and the mass-dependent detection efficiency of ion detectors. General quantitative ionization and desorption interpretations of ion production are described. Important instrument parameters and available methods of MALDi-TOF MS used for quantitative analysis are also reviewed.