An enzymatic amplification cycle for high sensitive immunoassay

✍ Scribed by Frank F Bier; Eva Ehrentreich-Förster; Alexander Makower; Frieder W Scheller

• Book ID: 102624778
• Publisher: Elsevier Science
• Year: 1996
• Tongue: English
• Weight: 488 KB
• Volume: 328
• Category: Article
• ISSN: 0003-2670
• DOI: 10.1016/0003-2670(96)00046-3

✦ Synopsis

An amplification cycle consisting of oligosaccharide dehydrogenase (ODH) and lactase is found to be highly sensitive to several catecholamines and p-aminophenol. An immunoassay is constructed by combining this amplification cycle with a suitable enzyme label, of which p-aminophenol is the product of the enzymatic reaction. Alkaline phosphatase and ,f?galactosidase were tested as labels for immunoglobulin G from goat (gtIgG) and human thyroid stimulating hormone (hTSH) immunoassay. The combination of enzymatic amplification cycles with a sandwich type immunoassay yields high sensitivity measurement of hTSH. The assay was found to have two linear ranges: the first one is between 0.2 and 20 q/ml, the second one from 0.0005 to 0.5 ng/ml, depending on assay procedure. Both together cover well the diagnostically relevant range of O.l-lOOmU/l (0.017-17 ng/ml); the detection limit is at 0.3 pg/ml (1.8 pU/l).