title: A micro-method for measuring total protein in cerebrospinal fluid by using benzethonium chloride in microtiter plate wells.
abstract: By using a benzethonium chloride concentration 12-fold that described originally (Clin Chem 1979;25:1317-9), we developed a reliable method suitable for routine measurement of total protein in cerebrospinal fluid. Only 10 microL of sample is required. Reactivity to immunoglobulin G (IgG) and to albumin (Alb) is similar, as is necessary for specimens that can have very varied IgG/Alb ratios. The assay, performed in a microtiter plate for ease of use, has a between-batch coefficient of variation of 3.4% for a protein concentration of 450 mg/L. This contrasts with a dye-binding technique with Ponceau S, for which the CV was 9% at the same concentration.
authors: Department of Special Chemical Pathology, National Hospitals for Nervous Diseases, London, England.
authors: R W
authors: RW
authors: Luxton
authors: P
authors: P
authors: Patel
authors: G
authors: G
authors: Keir
authors: E J
authors: EJ
authors: Thompson
mesh_terms: D000418:Albumins / Q000134:cerebrospinal fluid; D001391:Azo Compounds; D001558:Benzethonium; D002556:Cerebrospinal Fluid Proteins / Q000032:analysis*; D006801:Humans; D000644:Quaternary Ammonium Compounds; D014168:Transferrin / Q000134:cerebrospinal fluid; D005719:gamma-Globulins / Q000134:cerebrospinal fluid
chemical_list: D000418:Albumins; D001391:Azo Compounds; D002556:Cerebrospinal Fluid Proteins; D000644:Quaternary Ammonium Compounds; D014168:Transferrin; D005719:gamma-Globulins; D001558:Benzethonium; C032756:ponceau S