Sampling and homogenization of tissues are critical for accessing tissue molecules for omics analysis. Traditional methods, like cutting and bead milling, often cause the release of enzymes from cell compartments, which can alter the original molecular composition.
We have developed a novel laser-based instrument utilizing nano-second or pico-second infrared laser systems (NIRL, PIRL). These systems rapidly and gently convert tissue into an aerosol, preserving even labile proteins and their conformations. The resulting aerosol condensate can be directly analyzed via mass spectrometry or prepared for various omics applications, including lipidomics, metabolomics, proteomics, and transcriptomics. NIRL and PIRL have the capability to sample both soft tissues, like brain and liver, and hard tissues, like bones and teeth. This method is particularly beneficial for studying proteoforms, as it minimizes the risk of proteolytic modifications that typically occur during sample preparation. Our 3D-MTiLAb system combines NIRL or PIRL with light and fluorescence microscopy, a high-resolution camera, and optical coherence tomography (OCT). This setup allows for precise selection and targeted sampling of tissue areas in three dimensions. With a single laser shot, a volume of 20 x 20 x 20 µm is ablated.
In summary, the 3D-MTiLAb is ideal for targeted, soft and fast sampling of any kind of tissue, guided by diverse imaging systems, giving the opportunity to measure the omes of different biomolecule classes with spatial resolution and to getting closer to their original composition in tissues.