Assessment of a comparison of colorimetric methods used for oxytocinase determination.

The correlation of three colorimetric oxytocinase determination methods used in clinics was compared and assessed. It was found that the new methods, the method of Kleiner and Brounet-Yager, and that of Usategui-Gomez et al., show a high correlation with respect to the Tuppy and Nesvadba method (modified by Klimek) the usefulness of which has already been proved. The method of Usategui-Gomez et al., using L-cystine-bis-p-nitroanilide as substrate, is more sensitive and has more advantages.