One way of imaging tiny vasculature like that found in the brain requires injections of fluorescing particles that emit a glow that can be picked up by external equipment. The quality of the obtained image depends to a large degree on the fluorescence intensity of the injected particles. The brighter they glow, the more we can learn about the details of the brain and other small scale bits of anatomy.
A team of researchers based in France has synthesised a new material that glows better than any other similar substance. This Lem-PHEA chromophore has been successfully tested in imaging the cerebral vascular system of a mouse under 3D two-photon microscopy.
From the study in journal Chemical Science:
A water soluble Lemke chromophore derivative shows an unusual polarity dependence of its emission efficiency, leading to strong red-NIR fluorescence in water when fitted with appropriate water-solubilizing polymer chains. In this edge article, the synthesis of the chromophore is described. The dependence of its fluorescence on solvent polarity is investigated experimentally and rationalized on the basis of ab initio calculations. Finally, we demonstrate that this chromophore is a valuable candidate for in vivo two-photon imaging of cerebral vasculature, with two-photon absorption and emission in the biological transparency window.
Press release: Brilliant dye to probe the brain…