title: Determination of hematoporphyrin and protoporphyrin by ion-pair extraction with chlorpromazine.
abstract: A sensitive method based on ion-pair extraction is described for the quantification of hematoporphyrin and protoporphyrin using chlorpromazine as an ion-pair-forming agent. Extraction of the ion-pair in chloroform is obtained quickly at an optimum pH of 6.5 for hematoporphyrin and 6.5-6.8 for protoporphyrin, giving an excellent recovery of the porphyrin. A stoichiometric relationship of 1:2 between porphyrin and chlorpromazine is proved. Cyanocobalamin and liver extract do not interfere with the assay.
mesh_terms: D055598:Chemical Phenomena; D002627:Chemistry, Physical; D002746:Chlorpromazine; D006415:Hematoporphyrins / Q000032:analysis*; D006863:Hydrogen-Ion Concentration; D007474:Ion Exchange; D008110:Liver Extracts; D011166:Porphyrins / Q000032:analysis*; D011524:Protoporphyrins / Q000032:analysis*; D014805:Vitamin B 12
chemical_list: D006415:Hematoporphyrins; D008110:Liver Extracts; D011166:Porphyrins; D011524:Protoporphyrins; D014805:Vitamin B 12; D002746:Chlorpromazine