A Matrix Sublimation Device with an Integrated Solvent Nebulizer for MALDI-MSI

Abstract

The current matrix deposition methods in MALDI-mass spectrometry imaging (MALDI-MSI) face technical problems related to the inhomogeneous distribution of crystals and the low analyte extraction and cocrystallization efficiency. In this work, an integrated matrix sublimation device with synchronous solvent nebulization was developed for MALDI-MSI. Droplets of solvents were directly introduced into the chamber of the sublimator by using a miniaturized ultrasonic nebulizer unit. The synchronous and asynchronous working modes of solvent nebulization and matrix sublimation were systematically investigated. Imaging of both protein and small metabolite distributions in mouse brain tissue sections was successfully performed using the developed matrix deposition device. The sensitivity and quality of the images were clearly improved in synchronous mode compared with those of the conventional spray and sublimation methods. These results demonstrate that the integrated device with both solvent nebulization and matrix sublimation is a useful tool in MALDI-MSI applications.

Single-cell and spatial multi-omics in the plant sciences: Technical advances, applications, and perspectives

“…Similar to DESI-MSI, MALDI-MSI uses soft ionization ( Zhu et al., 2021 ), and it detects masses up to 100 000 Da ( Stoeckli et al., 2001 ). However, sample ionization requires deposition of an organic matrix, making the experimental operating conditions more complex than those of SIMS or DESI-MSI ( Li et al., 2022a ). MALDI-MSI usually achieves a resolution of about 5 μm ( Feenstra et al., 2017 ).…”

Mass Spectrometry in China

“…Wang et al used caffeic acid as the matrix for MALDI so proteins of molecular weights close to 200 000 Da could be efficiently imaged . Chen, Chan et al designed an integrated device for studying and optimizing the deposition of matrix for MALDI MS imaging . Computational methods are also critical in MS imaging due to the high complexity and dimensionality of the data.…”

“…26 Chen, Chan et al designed an integrated device for studying and optimizing the deposition of matrix for MALDI MS imaging. 27 Computational methods are also critical in MS imaging due to the high complexity and dimensionality of the data. Huang et al developed a method for automatic registration of the MSI data for sagittal brain sections to a reference atlas by adding auxiliary lines between brain regions.…”

How to sample a seizure plant: the role of the visualization spatial distribution analysis of Lophophora williamsii as an example

“…More refined MSI results are affected by many parameters, such as the sample preservation method [ 18–20 ], slicing techniques [ 21 , 22 ], sample preparation method [ 23–27 ], sample embedding/fixation method [ 28–30 ], auxiliary matrices [ 31 , 32 ], and sampling ionization profile (laser diameter, ion beam, or surface contact area) [ 33 ]. In addition, for MALDI, the distribution of the sprayed matrix [ 34 , 35 ] and participation of the biological sample’s own matrix elements [ 36 ] are further influencing factors that cannot be ignored. For succulent plants, the above effects may be more noteworthy in the MSI analysis.…”