Total nitroso compounds in gastric juice

A method is described for the measurement of 'total nitroso compounds' in gastric juice. It is applicable to small samples and in the presence of food. The method depends on treatment with hydrazine sulfate at pH 4 to destroy nitrite, decomposition by addition of the sample to HBr/acetic acid in boiling ethyl acetate and determination of the nitric oxide evolved by a chemiluminescence analyser. The method is being applied to a study of samples from healthy subjects throughout 24 hours of normal diet, prior to similar studies with patients.