ReportBioanalysis

Mass spectrometry imaging with laser-induced postionization

See allHide authors and affiliations

Science  05 Mar 2015:
aaa1051
DOI: 10.1126/science.aaa1051

You are currently viewing the abstract.

View Full Text

Abstract

Matrix-assisted laser desorption/ionization mass spectrometry imaging (MALDI-MSI) can simultaneously record the lateral distribution of numerous biomolecules in tissue slices, but its sensitivity is restricted by limited ionization. We used a wavelength-tunable postionization laser to initiate secondary MALDI-like ionization processes in the gas phase. In this way we could increase the ion yields for numerous lipid classes, liposoluble vitamins and saccharides, imaged in animal and plant tissue with a 5 micrometer-wide laser spot, by up to two orders of magnitude. Critical parameters for initiation of the secondary ionization processes are pressure of the cooling gas in the ion source, laser wavelength, pulse energy, and delay between the two laser pulses. The technology could enable sensitive MALDI-MS imaging with a lateral resolution in the low micrometer range.

View Full Text