After separating porphyrins as their metllyl esters .by .Gilica gel rtlhb-!layar chromatograpliy, in the analytical range, a. complementary fluoromekic m;leffhod ma5 developed for quantitative iqz sit?4 fluorometry of porphyrin tllin-layeri~l~on;l~~~~sunns. Commercial silica gel layers with an aluminium foil base ,are lused. 'il%e dhmesaem~oe intensity of the porphyrin zones in the chromatogram was con%inuous'&y n;e@i&en;edl on a Camag-Turner TLC-Scanner (primary filter Kodak-Wratken -4.,7-B, seacmdhry filter Kodak-Wratten 25 ; photomultiplier HTV-136). Using subsequent ~sgeobq@xt~~metric analyses of the same material, factors were calculated for it!he quax&iitiakii~e evaluation of the fluorescence peaks of two or more porphyrins inleach c1iaomarb~gxam~, thus permitting tile determination of the percentage distribution ofrt!tle ~pcq$lgkirms in the separated mixture. The sensitivity of the metllod is such that ~armouz~tts~~~~kss than 1 ng of porphyrin methyl ester/mm2 of silica gel surface (layer itlkkz2ess~o..2 mxm)) can lx detected. The reproducibility depends mainly on the use 10-f ;t%e -same s%iicca~&l material in eacll analytical series, tile quality of the chromatogr~Ll~lldc-s~a~artiicim, ttbe careful adjustment of the primary light, and the complete evapora;t:ion lof $Jhe:sokerxts from the layer. Under identical conditions the coefficient of varialGlit_rvzaqgestiom n to soA, in groups of five similar chromatograms.
The method of fluorescenoexxmtikq OF porpl~yrins in tllin-layer chromatograms is best suited for serial ~detertiintions, and has found application in the clinical chemistry of hepatic qxxplqrias :and ii:n studies on microbial tetrapyrrol l~iosyntliesis.