Abstract
This paper deals with an examination of the methods of estimation of thiamine propyldisulfide (TPD)-^<35>S which was a part of our program for the study of the absorption and excretion of TPD. It was revealed that, when an aqueous solution of TPD-^<35>S was dried by infrared rays, its side-chain of propylsulfide was decomposed into a volatile compound. Therefore, it is necessary to convert sulfur to sulfate and determine as Ba^<35>SO_4. It is recommended to carry out the estimation of ^<35>S as Ba^<35>SO_4 to the thickness of about 30 mg.
