Assays for Porphyrins, δ-Aminolevulinic-Acid Dehydratase, and Porphyrinogen Synthetase in Microliter Samples of Whole Blood: Applications to Metabolic Defects Involving the Heme Pathway

Abstract

Three micromethods are described for the assay of enzymes or products of the heme biosynthetic pathway in blood. A fluorometric method for the assay of protoporphyrin may be applied to the rapid screening of children for chronic lead poisoning. A colorimetric assay for delta-aminolevulinic-acid dehydratase may be applied to the detection of acute and chronic lead poisoning. A fluorometric assay for porphyrin formation from prophobilinogen is also described.