Abstract
The previous paper reported the two methods for the determination of thioctic acid, i.e., a spectrophotometric and a colorimetric method, which based on the fact that a mercaptide was formed quantitatively with dihydrothioctic acid and p-chloromercuribenzoate. The recovery rates of the method were studied for blood samples, i.e., a definite amount of thioctic acid was added to rabbit plasma, it was extracted with ethylacetate, the ethylacetate fraction was washed by acid phosphate buffer, and extracted by alkaline solution, then thioctic acid in the ethylacetate fraction was transferred quantitatively to alkaline solution. This procedure was useful for removing the interferring action of other components in the blood, particularly glutathione, cysteine or salts of heavy metals.
