DESI PI/DESI Mass Spectrometry Imaging Technology

Mass spectrometry imaging, in simple terms, is the use of mass spectrometry to visualise molecules. It was first proposed in 1997 by Richard Caprioli and colleagues at Vanderbilt University. It is currently of immense value in numerous fields, including medical research, biological research and pharmaceutical research, and has become a major focus of mass spectrometry research. Our company currently utilises the DESI PI/DESI method for mass spectrometry imaging.

Principle of DESI PI/DESI: In DESI PI, the section is first dissolved using dissociative electrospray, after which the dissolved sample is drawn in via the sample loop and subjected to secondary photoionisation. Unlike DESI, this method enables the imaging of non-polar substances.

The mass spectrometry method adopted by our company enables molecular imaging of a wide range of polar and non-polar substances through switchable photoionisation.

A) Schematic diagram of the DESI/PI experimental setup (enlarged cross-sectional view of the photoionisation interface);

B) A photograph of the DESI/PI setup;

C) A krypton lamp.

Features of DESI PI/DESI:

1. In positive ion mode: this photoionisation imaging source improves the detection limits for creatine, cholesterol and GalCer lipids in mouse brain sections by more than two orders of magnitude;

2. In negative ion mode: the sensitivity for glutamine and certain lipids can also be increased several-fold.

3. Furthermore, for certain highly polar neurotransmitters and lipids, this photoionisation imaging source can also achieve a significant improvement in sensitivity.

Areas of application

Spatial metabolomics, pathological diagnosis, pharmacokinetics, toxicology, environmental chemistry, forensic science, archaeology, palaeontology