| 摘要 |
1395253 Determination of thyroxine &c. MALLINCKRODT CHEMICAL WORKS 20 June 1972 [12 July 1971] 28862/72 Heading G1B A method for determining a physiologically active substance in a body fluid, the substance being one capable of being bound by a body fluid component comprises mixing a labelled form of the substance, optionally in bound form, a predetermined amount of a first portion of the body fluid containing the substance to be determined but with a known major proportion of the binding component for the substance removed, and a predetermined amount of a second portion of the body fluid containing unsaturated binder for the substance and the associated active substance, separating the labelled substance bound to the binding component from the unbound labelled substance and then measuring either bound or unbound labelled substance. An example relates to determination of an "effective thyroxine ratio" which is related to the amount of unbound thyroxine in the sample by a method comprising mixing the serum to be tested with a reagent comprising barbital buffered normal serum containing thyroglobulin bound I-125 labelled thyroxine mixing an aliquot of a thyroxine solution, prepared by deproteinising a sample of the serum to be tested, with the same reagent, mixing the two sample-reagent solutions, adding a strip of anion selective ion exchange membrane and incubating, the membrane strip then being removed and the solution counted. There is reference to determination of cortisol and of plasma iron. |
