Anions in non saline waters - Determination of Anions in Natural and Treated Waters - page 161

The other method [229], involves the use of peroxidase, in which non-fluorescent
homovanillic acid is converted by hydrogen peroxide into the highly fluorescent 2,2 ′ -
dihydroxy-3,3 ′ -dimethoxybiphenyl-5,5 ′ -diacetic acid:
2.23.3 Chemiluminescence methods
One method is based on the inhibiting action of this anion on the chemiluminescence of
luminol with hydrogen peroxide in the presence of copper(II) [265]. The induction period
increases with increase in the concentration of cyanide and the logarithm of the induction
period is proportional to the concentration of cyanide.
Ishii et al. [266] used flow injection analysis with chemiluminescence detection for
determining very low levels of cyanide in non saline waters by means of the uranine-
sodium hydroxide-didocecyldimethylammonium bromide system. The emission induced
by cyanide is efficiently sensitised by uranine in organised surfactant aggregate bilayer
vesicles solution. The method is selective for cyanide and has a detection limit of
3×10 −10 M for continuous sample flow and of 2×10 −9 M for 20µL sample injection. The
relative standard deviation was 2.1% ( n =10) for 0.05ng of cyanide.
2.23.4 Atomic absorption spectrometry
Rosentreter and Skogerboe [267] and Razmilic [268] have described an atomic
absorption spectrometric method for the determination of sub-ppm concentrations of
cyanide in non saline waters.
Haj-Hussein et al. [269] have developed a flow injection method for the determination
of cyanide ion by atomic absorption spectrometry. Aqueous cyanide samples (pH 11.0)