Vanadium (III) gives a greenish- yellow complex with anthranilic acid in presence of
pyridine. The complex is extractable with chloroform and is used for photometric
determination of vanadium by measuring the absorbance at 390 nm against a reagent
blank. Beer's Law holds good in the range of 1-20 pg V/ml. Moderate amounts of Pb
(II) , Ca (II) , Sr (II) , Ba (II) , Cd (II) , Mg (II) , Mn (II) , Ni (II) , Co (II) , Cu (II) , Zn (II) and limited amounts of W (VI), A1 (III), Th (IV), Zr (IV), Sn (II), Sb (III), Ti(IV), Fe (III), and Cr (VI) can be tolerated. U (VI) and Mo (VI) interfere