Light from a blacklight lamp (General Electric BLB) is restricted to a waveband range 360 - 470 nm by cut-off filters consisting of 4cm 1 M aqueous CuSO4 and acrylic plastic sheets. This filtered lamp emission is used to excite the characteristic red fluorescence of chlorophyll and its derivatives on paper or thin-layer chromatograms. Fluorescent spots are detected and recorded by exposure of red-sensitive panchromatic photographic printing paper (Kodak Panalure) to the fluorescing chromatogram. A thin yellow filter interposed between the chromatogram and the photo print paper restricts the detected fluorescence to wavelengths greater than about 500 nm. Standard development of the photoprint yields grey to black spots on a white background. Intensity and size of the recorded spot is proportional to the amount of a single chlorophyll derivative on the chromatogram over a limited range of pigment applied to the chromatogram. A one-minute exposure with filtered light from an 8 watt GE BLB lamp at a 10-cm distance will record 0.3 nanomole (270 nanogram) chlorophyll a on Whatman No. 1 or on Whatman 3 MM paper chromatograms. Detection of chlorophyll derivatives by this technique is at least 10-fold more sensitive than visualization of the pigment spots on the chromatograms by their green color. This fluorographic technique can be a useful adjunct to chromatographic analyses of porphyrins in general.

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