Combined batchwise and continuous flow mechanization of solid-phase radioimmunoassays.

A new modification of the "coated-tube"-technique for the radioimmunoassay of human placental lactogen is described. Polyvinylchloride capillaries are used as reaction-vessels. Most working steps of the test procedure are mechanized. The possibilities and limitations of the new technique are discussed. The reliability of the method was shown by a recovery test, dilution tests, reproducibility and a comparison of the results for 71 sera, ranging from the 6th to the 42nd week of pregnancy, with those obtained by a conventional assay procedure.