title: Factors affecting determination of delta-aminolevulinate by use of Ehrlich's reagent.
abstract: We investigated the formation of delta-aminolevulinic acid (ALA)-pyrrole and subsequent color development used in determining ALA in urine. Of three condensation reagents examined--acetylacetone, ethyl acetoacetate, and methyl acetoacetate--the last was the best. When the ALA-pyrrole is reacted with Ehrlich's reagent in ethyl acetate according to one procedure, the optimum concentration of perchloric acid in the reagent is 0.5 to 1.0 mol/L. Its optimum concentration is 1.0 to 2.3 mol/L when the reaction takes place in water.
mesh_terms: D000622:Aminolevulinic Acid / Q000652:urine*; D001547:Benzaldehydes; D003124:Colorimetry; D006801:Humans; D007855:Lead Poisoning / Q000175:diagnosis / Q000652:urine; D007982:Levulinic Acids / Q000652:urine*; D012997:Solvents; D013053:Spectrophotometry; D014867:Water
chemical_list: D001547:Benzaldehydes; D007982:Levulinic Acids; D012997:Solvents; D014867:Water; D000622:Aminolevulinic Acid; C510241:p-dimethylaminobenzaldehyde