title: Precision and accuracy of a HPLC method for measurement of fecal porphyrin concentrations.
abstract: We studied precision and accuracy of a HPLC method for determination of porphyrins in feces. A commercial standard solution appeared to contain less coproporphyrin (15%) than stated by the manufacturer. The between-batch coefficients of variation were often below 15% and were higher than the within-batch coefficients. The precision of porphyrin measurements was not influenced by the type of porphyria. Recoveries of added coproporphyrin and protoporphyrin were 90% and 108%; coefficients of variation were 6% and 19%, respectively.
authors.affiliation: Department of Clinical Chemistry, Deventer Ziekenhuis, Deventer, The Netherlands. Zuijderf@DZ.nl
authors.forename: Floris M J
authors.initials: FM
authors.lastname: Zuijderhoudt
authors.forename: Johannes S
authors.initials: JS
authors.lastname: Kamphuis
authors.forename: Willem E
authors.initials: WE
authors.lastname: Kluitenberg
authors.forename: Jenneke
authors.initials: J
authors.lastname: Dorresteijn-de Bok
mesh_terms: D002851:Chromatography, High Pressure Liquid; D003306:Coproporphyrins / Q000032:analysis; D005243:Feces / Q000737:chemistry*; D006801:Humans; D011164:Porphyrias / Q000175:diagnosis*; D011166:Porphyrins / Q000032:analysis*; D011524:Protoporphyrins / Q000032:analysis; D012680:Sensitivity and Specificity
chemical_list: D003306:Coproporphyrins; D011166:Porphyrins; D011524:Protoporphyrins; C026971:coproporphyrin III; C031467:coproporphyrin I