Visualization of Amyloid-Beta Peptides in Human Cortical Brain Slices

Take a glass slide containing a cortical slice of brain tissue collected from an Alzheimer's patient. The tissue contains insoluble amyloid-beta deposits within the parenchyma and cerebral capillaries.

Immerse the slide in diluted alcohol to remove lipids and salts.

Wash with absolute alcohol to dehydrate the tissue, then apply a fixative to preserve the tissue architecture.

Vacuum dry the slide, removing any moisture.

Treat with formic acid vapor in a humidified environment to break down amyloid-beta aggregates into smaller soluble peptides.

Using an optical scanner, generate images of the tissue's structural features to interpret data from the imaging mass spectrometry.

Spray a matrix solution over the specimen.

Using a mass spectrometer, apply a laser that the matrix absorbs to ionize the peptides. A detector then identifies them based on their mass-to-charge ratio.

Analyze the data to produce images, revealing the distribution of amyloid-beta peptides in the tissue parenchyma and cerebral capillaries.