A comparison is made between determination of porphyrin methyl esters by high performance liquid chromatography (HPLC) with absorbance detection and with fluorimetric detection. Detection limits with absorbance detection vary from 0.8 pmol for 2-COOH-porphyrins to 5 pmol for 8-COOH-porphyrins. With fluorometric detection the corresponding figures are 0.04 pmol and 0.4 pmol. Fluorimetric detection also has a better reproducibility, and it is more specific than absorbance detection. The use of HPLC with fluorimetric detection thus permits rapid, highly efficient and specific quantitative detection and identification of porphyrins in complex biological samples.
