ACS_ Analytical Chemistry_ Front cover Picture
July 8, 2020Volume 12, Issue 27Pages 30021-31036
Compartmentalized Arrays of Matrix Droplets for Quantitative Mass Spectrometry Imaging of Adsorbed Peptides
Mass spectrometry imaging (MSI) based on matrix-assisted laser desorption/ionization (MALDI) provides information on the identification and spatial distribution of biomolecules. Quantitative analysis, however, has been challenging largely due to heterogeneity in both the size of the matrix crystals and the extraction area. In this work, we present a compartmentalized elastomeric stamp for quantitative MALDI-MSI of adsorbed peptides. Filling the compartments with matrix solution and stamping onto a planar substrate extract and concentrate analytes adsorbed in each compartment into a single analyte-matrix cocrystal over the entire stamped area. Walls between compartments help preserve spatial information on the adsorbates. The mass intensity of the cocrystals directly correlates with the surface coverage of analytes, which enables not only quantitative analysis but estimation of an equilibrium constant for the adsorption. We demonstrate via MALDI-MSI relative quantitation of peptides adsorbed along a microchannel with varying surface coverages.
- Sanghwan Park
- Sook Yoon
- Hyegi Min
- Seung Min Moon
- Yoon Ji Choi
- Il Shin Kim
- Ga Hyang Lee
- Min Sun Kim
- Jungju Seo
- Woonggyu Jung
- Chang Young Lee
https://pubs.acs.org/doi/10.1021/acs.analchem.9b05316
Image created by minjeong Kim / Nanosphere
ACS_ Analytical Chemistry_ Front cover Picture
Compartmentalized Arrays of Matrix Droplets for Quantitative Mass Spectrometry Imaging of Adsorbed Peptides
Mass spectrometry imaging (MSI) based on matrix-assisted laser desorption/ionization (MALDI) provides information on the identification and spatial distribution of biomolecules. Quantitative analysis, however, has been challenging largely due to heterogeneity in both the size of the matrix crystals and the extraction area. In this work, we present a compartmentalized elastomeric stamp for quantitative MALDI-MSI of adsorbed peptides. Filling the compartments with matrix solution and stamping onto a planar substrate extract and concentrate analytes adsorbed in each compartment into a single analyte-matrix cocrystal over the entire stamped area. Walls between compartments help preserve spatial information on the adsorbates. The mass intensity of the cocrystals directly correlates with the surface coverage of analytes, which enables not only quantitative analysis but estimation of an equilibrium constant for the adsorption. We demonstrate via MALDI-MSI relative quantitation of peptides adsorbed along a microchannel with varying surface coverages.
https://pubs.acs.org/doi/10.1021/acs.analchem.9b05316
Image created by minjeong Kim / Nanosphere