Mass Spectrometry Imaging of Mouse Liver Tissue and Zebrafish Using Nested Regions of Interest

In a recent study published in the Journal of the American Society of Mass Spectrometry, a team of researchers from North Carolina State University introduced a novel mass spectrometry imaging (MSI) method that could reduce data acquisition times while preserving vital spatial and chemical information (1). The study used nested regions of interest (nROI), which is a MSI method that reduces MSI data acquisition time with step-size imaging, to examine zebrafish (1).

aquarium fish, zebrafish on a blue background | Image Credit: © peter verreussel - stock.adobe.com

MSI is an analytical technique used to visualize the spatial distribution of molecules within a sample, offering invaluable insights into various fields, from biology to materials science (1). However, one persistent challenge in MSI has been the trade-off between spatial resolution and data acquisition time, meaning that one of these variables often comes at the expense of the other (1). For example, increasing the spatial resolution means that the acquisition time will be longer, which could be problematic for analysts studying larger biological specimens.

The research team showed how the nROI method could improve spatial resolution and data acquisition time. nROI captures high-resolution images of specific regions of interest within a sample while simultaneously imaging the surrounding areas at a lower resolution (1). This conservation method allows researchers to obtain the chemical and spatial information from the target regions while reducing the data acquisition time (1).

As a result, the nROI method is better suited for analyzing larger biological specimens. To validate the method, the research team studied mouse liver tissue, which is a larger specimen than what normally is examined. They found that the nROI technique generated detailed images while decreasing the acquisition time (1). The team also applied the nROI method to top-hat MSI of zebrafish using an innovative optical train, resulting in an improvement in both acquisition speed and spatial detail (1).

Because of its benefits, the nROI method could become a tool for scientists conducting MS experiments to explore molecular spatial distribution on a greater scale. With the potential to accelerate discoveries in biology and medicine, this method is an alternative way to study large biological specimens while still getting the information scientists need.

Reference

(1) Joignant, A. N.; Ritter, M. M.; Knizner, K. T.; Garrard, K. P.; Kullman, S. W.; Muddiman, D. C. Maximized Spatial Information and Minimized Acquisition Time of Top-Hat IR-MALDESI-MSI of Zebrafish Using Nested Regions of Interest (nROIs). J. Am. Soc. Mass Spectrom. 2023, 34 (9), 2043–2050. DOI: 10.1021/jasms.3c00210