Analytical utility of bimetallic ternary complexes of alizarin fluorine blue Spectrophotometric determination of nickel

Mixtures of La(3+) and Ni(2+) ions form with Alizarin Fluorine Blue (1,2-dihydroxyanthraquinon-3-ylmethylamine-N,N-diacetic acid; AFB) the ternary complex (AFB)(2)La. Ni(n-) which has maximum light absorption at 550 nm ( = 1.13 x 10(4)); K(cond) = 1.9 x 10(5) lmole(-1) at pH 4.5 and 25 degrees , ionic strength = 0.1. The use of this complex for the photometric determination of nickel has been investigated.