Abstract: | A new chemical approach to the assay of synthetic folic acid has been investigated. Folic acid is cleaved with bisulphite to give a pteridine fraction and p-amino-benzoylglutamic acid. Acid hydrolysis and subsequent esterification converted the aromatic amine to ethyl p-aminobenzoate. This ester, when analysed by gas chromatography (g.l.c.), gave consistent yields averaging 49% from 50 to 1000 μg of folic acid. The recovery being predictable, the percentage yield can be used as a correction factor for unknown samples. The present procedure can be used for synthetic folic acid. |