Abstract
Phosphate is found in acid hydrolysates of vitamin B12. Such hydrolysates are deeply coloured and, in order to determine phosphate in them colorimetrically, it has been necessary to develop a new application of the unidimensional paper-strip partition chromatogram technique. The atomic ratio of cobalt: phosphorus in vitamin B12 is found to be 1:1. From a comparison of this result (3 above) with the values recorded by Smith for the anti-pernicious anæmia factor of Smith and Parker6, it is concluded that the latter compound is not identical with vitamin B12.