Quantitative Detection of Minute Concentrations of Digitoxin.

Abstract

The detection and quantitations of fractions of a microg. of digitoxin in Tyrode''s soln., rat serum and in human serum is reported. As little as 0.005 microg. of digitoxin per cc. of Tyrode''s soln. could be detected by the embryonic duck heart method. Rat and human sera inhibited the action of digitoxin on the embryonic duck heart quite markedly.