New mass spectrometry imaging platform for precise and tunable spatial analysis of biological samples

Problem

Implementation of mass spectrometry (MS) imaging for analysis of biological samples in clinical and pharmaceutical settings is rising.1,2 Allowing imaging of thousands of molecules simultaneously, MS imaging has become invaluable in applications ranging from disease diagnosis to drug discovery. Various MS imaging techniques have been developed which use a sampling probe to extract molecules from liquid on a sample’s surface. The probe size determines the spatial resolution achieved and cannot be changed without impractical hardware changes. This lack of spatial control greatly limits many MS imaging techniques to only a few applications. A system allowing for tunable and controllable spatial analysis is needed to expand the window of possible biological applications.

Solution

The Eberlin Lab at The University of Texas at Austin has developed a new MS imaging technique for spatially controlled analysis of biological samples. A piezoelectric dispenser first deposits solvent nanodroplets in a microarray on a sample’s surface. After molecules are extracted into the nanodroplet, a conductive capillary serves to pick up and transmit molecules to the mass spectrometer for detection. The diameter of the droplet used in the sampling area precisely determines the spatial resolution, which is crucial for accurate spatial analysis but challenging using existing approaches. With the dispenser, the droplet diameter, and thus the spatial resolution, can be easily and precisely changed.

Recently published in JASMS, researchers show that this method is compatible for imaging of metabolic species from various tissues, including mouse brain, human ovarian, and human brain cancers.3 They also collected highly reproducible molecular signatures from human ovarian cancer cell lines. This technique offers an automated way to tune the spatial resolution without modifying equipment, opening up a multitude of biological applications compatible with a single platform. The Eberlin Lab’s MS imaging platform can streamline and improve analysis of biological samples for any application requiring accurate and controllable spatial resolution. UT is seeking partners to develop this platform technology as a tool for clinical research and diagnosis.

References

1.  Buchberger, A. R. et al., Anal. Chem. 2018, 90 (1), 240−265. https://doi.org/10.1021/acs.analchem.0c04759

2.  Perez C.J., et al. Rapid Commun Mass Spectrom. 2019, 33(S3): 27–53. https://doi.org/10.1002/rcm.8145

3.  Sans, M. et al., J Am Soc Mass Spectrom. 2020, 31 (2), 418-428. https://pubs.acs.org/doi/10.1021/jasms.9b00077