A rapid binding assay for immunoglobulins which may be used as an alternative to ammonium sulfate precipitation...

This paper describes the conditions under which a short column packed with Sephadex G-25 may be eluted centrifugally to separate labeled ligands from binding immunoglobulins in a manner which can yield quantitative binding information. This method may be used as an alternative to the classical binding assay involving ammonium sulfate precipitation. The advantage is a large saving in total assay time over that procedure. The column assay is applicable to antisera and purified polyclonal and monoclonal immunoglobulins. The restrictions are that the labeled ligands must be of molecular weight less than approximately 5000 Da.