Direct radioimmunoassay for antigens and their antibodies

A method is described for determining the presence of an antigen or an antibody (particularly hepatitis) capable of being bound to two associated antigens or antibodies in an unknown sample, utilizing direct radioimmunoassay. The antigen or antibody is placed in a buffer mixture or deionized water and is affixed to the test apparatus which is incubated and washed with the buffer mixture or deionized water. The unknown sample is placed in contact with the test apparatus and incubated for from 0.5 to 42 hours at 38 to 500C. The antigen or antibody in the unknown sample is thus bonded to the incubated test apparatus. The apparatus is washed to remove the sample and leave only bonded antigen or antibody. The washed test apparatus is then contacted with a purified form of antigen or antibody that is labelled with radioactive isotope (one of I125, I131, P32, and tritium). After incubating at 38 to 500C a radioactively traced, incubated coating is produced. Any unbonded purified form is removed. Counting radiation emitted from the incubated coating and comparing with the initial sample will indicate the presence or absence of bound antibody or antigen. (JTA)