High-Resolution MALDI-TOFMS Measurement and KMD Analysis for Visualization of Polymers Fractionated by Reversed-Phase LC
To analyze complex polymer samples in greater detail, it is effective to separate their components using liquid chromatography (LC) prior to mass spectrometric measurements. Electrospray ionization (ESI) offers excellent compatibility with LC and facilitates both measurement and analysis. However, it tends to produce multiply charged ions, which can complicate the spectra of complex polymer samples and hinder interpretation. In contrast, matrix-assisted laser desorption/ionization (MALDI) predominantly generates singly charged ions, making it more suitable for qualitative analysis of polymers. Reversed-phase LC enables separation based on differences in polymer hydrophobicity. Therefore, performing LC separation prior to MALDI-TOFMS analysis can yield more useful information from complex polymer samples.
In this study, we investigated the visualization of information obtained from high-resolution MALDI-TOFMS measurements of polymer fractions collected via reversed-phase LC, using Kendrick Mass Defect (KMD) plots. The analysis focused on the following two aspects: (1) Comparison of KMD plots before and after fractionation, and (2) Effect of different fractionation intervals (30 second / 15 second) on the visualization in KMD plots.