Sensitive derivative spectrophotometric determination of gold(III)
using 3,5-dimethoxy-4-hydroxybenzaldehyde isonicotinoyl
hydrazone (DMHBIH) in
presence of micellar medium
Chem.
Met. Alloys 4 (2011) 143-151
https://doi.org/10.30970/cma4.0180
G.V.S. VALLINATH, K.B.
CHANDRASEKHAR, N. DEVANNA
A simple and sensitive spectrophotometric
method has been developed for the determination of gold(III)
using the newly synthesized reagent 3,5-dimethoxy-4-hydroxybenzaldehyde
isonicotinoyl hydrazone (DMHBIH) in a neutral surfactant of Triton X-100 (5 %) (micellar
medium). Gold(III) forms an orange coloured
water soluble complex with the reagent in acidic medium pH 4.0. The molar absorptivity and Sandell’s
sensitivity of the coloured species are 1.14×105 l mol-1 cm-1 and 0.004587 μg/cm2,
respectively. Beer’s law is obeyed in the range 0.197-1.97 μg/ml of Au(III) at lmax at 386 nm.
The developed derivative spectrophotometric method
was satisfactorily applied for the determination of gold(III)
in synthetic mixtures, certified reference materials, water samples and
pharmaceutical samples.
Structure of 3,5-Dimethoxy-4-hydroxybenzaldehyde
isonicotinoylhydrazone (DMHBIH).
Keywords
Gold(III) /
3,5-dimethoxy-4-hydroxybenzaldehyde isonicotinoylhydrazone
(DMHBIH) / Micellar medium
/ Derivative spectrophotometry