title: Validation of the ultrafiltration technique for creatinine analysis by HPLC: a comparison with direct serum injection.
abstract: The determination of creatinine by HPLC was performed by direct injection of serum onto the column, and after ultrafiltration of the sample, and the results were compared. A modified weak cation exchange column was used for HPLC. This eliminates the protein displacement effect and the Gibbs-Donnan effect, thus permitting a rapid direct analysis. Three of the four ultrafiltration methods gave almost identical analytical results. Regression analyses of the results from direct serum injection versus ultrafiltration showed a bias of 5% on the slope y = 1.050 . xpure serum + 1.856, which was in our view solely due to the volume displacement effect of the proteins; correction of each data point by a protein-dependent correction factor resulted in an almost perfect regression line.
authors: Department of Clinical Chemistry, Academic Hospital Rotterdam-Dijkzigt, The Netherlands.
authors: L
authors: L
authors: Zwang
authors: B G
authors: BG
authors: Blijenberg
mesh_terms: D001798:Blood Proteins / Q000032:analysis; D002851:Chromatography, High Pressure Liquid; D003404:Creatinine / Q000097:blood*; D006801:Humans; D012044:Regression Analysis; D014462:Ultrafiltration
chemical_list: D001798:Blood Proteins; D003404:Creatinine