title: Rates of plasma porphyrin disappearance in fluorescent vs. red incandescent light exposure.
abstract: The rates of porphyrin disappearance in plasma specimens were assessed during exposure to standard fluorescent room lighting. Protoporphyrin half-life in specimens from patients with erythropoietic protoporphyria appeared to be less than 30 min under these conditions. Uroporphyrin-coproporphyrin mixtures in plasmas of patients with porphyria cutanea tarda were more photostable, with half-lives measurable in terms of hours. All plasma porphyrins could be protected for several days from similar photodegradation by performing all blood drawing, processing, and assay procedures under ordinary red-incandescent illumination, and by storage in the dark.
mesh_terms: D001793:Blood Preservation; D003624:Darkness; D006207:Half-Life; D006801:Humans; D008029:Lighting; D011164:Porphyrias / Q000097:blood; D011166:Porphyrins / Q000097:blood*; D011524:Protoporphyrins / Q000097:blood
chemical_list: D011166:Porphyrins; D011524:Protoporphyrins