Description:

Mass spectrometry imaging (MSI) is a group of advanced analytical techniques, providing spatially resolved molecular information about complex surfaces. Amongst them, desorption electrospray ionization (DESI) offers ambient ionization capabilities with minimal sample preparation and no vacuum requirement. However, the applications of DESI-MSI are hindered by limitations in clearly defining spatial resolution, lacking a complete understanding of the desorption-ionization process, and an insufficient assessment of potential material alteration during analysis. These challenges are particularly pressing in heritage science, forensics, and food studies, where the balance between spatial resolution and non-destructive analysis is critical.

ARISE aims to address four key challenges: (i) the lack of standardized test targets for evaluating spatial resolution; (ii) limited applications of DESI on real, complex materials; (iii) insufficient characterization of the wetted area and ionization region; and (iv) inadequate assessment of immediate and long-term material impacts. By systematically addressing these challenges, the ARISE project aligns with existing European Union research infrastructures, such as E-RIHS and EuroBioImaging.

Graphical abstract of the ARISE project

Research challenges:

  • Current definitions for spatial resolution in mass spectrometry imaging of complex sample surfaces, such as tissues, cross-sections or art materials, lack standardized and reproducible reference materials.
  • Existing research on DESI-MSI processes focuses primarily on well-defined homogeneous surfaces (glass, silica, PTFE), resulting in a limited understanding of its performance on complex, realistic substrates.
  • The relationship between the wetted area affected by DESI solvent, and the effective ionization region requires clear analytical characterisation.
  • DESI is regularly described as a non-destructive technique without a clear understanding of the impacts of the analysis on sensitive material surfaces either in the short or the long term.

Research objectives:

  1. To prototype well-defined test targets for an improved definition and determination of resolution in DESI-MSI.
  2. To identify key imaging variables allowing for optimization of resolution using deep learning.
  3. To investigate and quantify the immediate and long-term impacts of DESI on non-ideal realistic substrates, providing guidelines for its application on sensitive materials.

ARISE is a two-year postdoctoral project funded by the Slovenian Research and Innovation Agency (grant number Z1-70005) starting on March 1st 2026 with a budget of €160k.

For further information, please contact Assistant professor Dr Tjaša Rijavec (Principal investigator)