Turbidimetric determination of transthyretin (prealbumin) with a centrifugal analyzer.
We describe a simple, rapid turbidimetric method for measuring transthyretin in human serum by use of a centrifugal analyzer (Cobas-Bio) and commercially available antiserum. The immunoturbidimetric reaction is monitored at 340 nm for 180 s, and the changes in absorbance after the antiserum is added are used to prepare a stable standard curve. The range of measurement is 10 to 520 mg/L. The CV for between-day precision was less than 5.0% for normal and low controls. Bilirubin up to 310 mumol/L and hemoglobin up to 225 mumol/L did not interfere, but triglycerides greater than 2.3 mmol/L falsely depress the results. The normal reference interval for adults, derived from data on subjects 20 to 65 years old (both sexes), is 193 to 376 mg/L. Concentrations are lower in children (67-302 mg/L) and in adults 65 or more years old (113-292 mg/L).
D000328:Adult; D000368:Aged; D002648:Child; D005260:Female; D006801:Humans; D007118:Immunoassay / Q000379:methods; D007231:Infant, Newborn; D008297:Male; D008875:Middle Aged; D009391:Nephelometry and Turbidimetry / Q000295:instrumentation; D011228:Prealbumin / Q000032:analysis*; D011786:Quality Control; D011933:Reagent Kits, Diagnostic; D012016:Reference Values; D013048:Specimen Handling
D011228:Prealbumin; D011933:Reagent Kits, Diagnostic