Experiments in scanning luminescence x-ray microscopy

Scanning luminescence x-ray microscopy is based on collecting visible light emission from a sample region illuminated by an x-ray microprobe. We have tested the resolution of the method using P31 phosphor grains, and have obtained luminescence images of dye-labelled polystyrene spheres and sodium salicylate crystals. However, we have observed no light emission from the dyes DAPI, ethidium bromide, Hoecst 33258, and rhodamine phalloidon. Present efforts are aimed at improving our understanding of the luminescence process so as to find appropriate dyes for imaging dye-labelled biological specimens.