Abstract
When a fresh tissue slice is placed on a graphene layer substrate and irradiated with a 532 nm continuous wave laser, the transmission mode desorption of biomolecules is found to be greatly enhanced enough to facilitate the mass spectrometry analysis. The subsequent ionization process with nonthermal atmospheric helium plasma jets enables production of sufficient amounts of molecular ions from a fresh hippocampal tissue, such as fragments of glycerolipid and sphingolipid, adenine, and cholesterol. Micrometer spatial resolution mass spectrometry imaging of the hippocampal tissue, which enables to clearly identify the spatial distributions of small molecules, is also achieved using 532 nm continuous wave laser and a single-layer graphene as an energy transporter.
