Correlative Imaging of Trace Elements and Intact Molecular Species in a Single-Tissue Sample at the 50 μm Scale

Elemental and molecular imaging play a crucial role in understanding disease pathogenesis. To accurately correlate elemental and molecular markers, it is desirable to perform sequential elemental and molecular imaging on a single-tissue section. However, very little is known about the impact of performing these measurements in sequence. In this work, we highlight some of the challenges and successes associated with performing elemental mapping in sequence with mass spectrometry imaging. Specifically, the feasibility of molecular mapping using the mass spectrometry imaging (MSI) techniques matrix-assisted laser desorption ionization (MALDI) and desorption electrospray ionization (DESI) in sequence with the elemental mapping technique particle-induced X-ray emission (PIXE) is explored. Challenges for integration include substrate compatibility, as well as delocalization and spectral changes. We demonstrate that while sequential imaging comes with some compromises, sequential DESI-ME imaging is sufficient to correlate sulfur, iron, and lipid markers in a single tissue section at the 50 mu m scale.

Automated summary

Elemental and molecular imaging are important in understanding disease pathogenesis, and performing sequential elemental and molecular imaging poses challenges and successes. While compromises may be involved, research shows that correlating sulfur, iron, and lipid markers in a single tissue section at the 50 μm scale is feasible with sequential DESI-ME imaging.