title: Measurement of DNA antibodies.
abstract: Modifications of the standard Farr technic for assaying DNA antibodies are presented; these result in improved separation of normals from abnormals, enhanced reproducibility, and simplicity of performance. The use of 0.4 M borate buffer extends the range of the assay, while a 0.1 M buffer aids differentiation when equivocal results are obtained. Centrifugation of vials prior to counting improves the reproducibility by approximately 3%. Polyethylene glycol, at a final concentration of 6 Gm. per 100 ml., can be substituted for ammonium sulfate, with some advantages.
mesh_terms: D000906:Antibodies / Q000032:analysis*; D002021:Buffers; D004247:DNA / Q000276:immunology*; D011863:Radioimmunoassay
chemical_list: D000906:Antibodies; D002021:Buffers; D004247:DNA