Synthesis and Analytical Studies of a New Bis-azo Dye: 2,6-Bis(9-hydroxyphenanthryl-10-azo) pyridine

Abstract

A new pyridyl bis-azo dye, 2,6-bis(9-bydroxypbclWltbryl-10-azo)
pyridine has been synthesized and proposed as a sensitive chromogenic
reagent for the determination of copper,  cobalt,  zinc and
cadmium. The molar  absorptivities are 5.8 x 10⁴  L mole^-1 cm^-1 at
556 nm for copper,  4.7 X 10⁴ L mole^-1 cm^-1 at  540 nm for cobalt,
6.4 X 10⁴ L mole^-1 cm^-1 at 556 nm for zinc and 6.0 X 10⁴ L
mole^-1 cm^-1 at 560 nm for cadmium. Other pbysico-chemical characteristics
bave been established spectrophotometrically. Trace levels
of copper in some foodstuffs bave been determined with the
reagent.