Chemiluminescence enzyme immunoassay for thyroxin with use of glucose oxidase and a bis(2,4,6-trichlorophenyl)oxalate-fluorescent dye system.
In this chemiluminescence enzyme immunoassay for thyroxin, glucose oxidase (EC 1.1.3.4) is the enzyme label and the bound and free fractions are separated by the double-antibody solid-phase technique. In the assay of enzyme activity, hydrogen peroxide generated from glucose substrate is measured by its chemiluminescence reaction with bis(2,4,6-trichlorophenyl)oxalate and 8-anilino-1-naphthalene-sulfonic acid. The measurable range of thyroxin is 2.5 to 200 micrograms/L. The coefficients of variation for thyroxin concentrations of 43.2 and 12.8 micrograms/L were 7.0% and 8.6% (intra-assay), and 6.4% and 12.3% (interassay), respectively. The proposed method is applicable to large-scale preliminary screening of neonates for congenital hypothyroidism, with samples consisting of dried blood spotted on filter paper.
D003409:Congenital Hypothyroidism; D005456:Fluorescent Dyes; D005949:Glucose Oxidase; D006801:Humans; D007037:Hypothyroidism / Q000097:blood / Q000175:diagnosis; D007124:Immunoenzyme Techniques; D007231:Infant, Newborn; D008163:Luminescent Measurements; D008403:Mass Screening; D010070:Oxalates; D011863:Radioimmunoassay; D013974:Thyroxine / Q000097:blood*
D005456:Fluorescent Dyes; D010070:Oxalates; C036521:bis(2,4,6-trichlorophenyl)oxalate; D005949:Glucose Oxidase; D013974:Thyroxine