Synthesis and Spectrophotometric Study of 2-(6-Bromo-2- benzothiazolylazo)-4-chloro phenol as an Analytical Reagent for Determination of Copper

الملخص

2-( 6-Bromo-2-benzothiazolylazo )-4-chloro phenol (6-Br-BTACl) has been synthesized , and
used for the spectrophotometric determination of microgram amounts of copper. This method
sensitive, selective and rapid for reaction between Cu+2 and (6-Br-BTACl), to form a green complex
having a molar ratio of 1:2 (Cu-6-Br-BTACl) at pH 3.7. The molar absorptivity of the complex is
(0.38x104 L.mol-1.cm-1) at λmax 636 nm. Beer’s law is obeyed in the range of 0.05 –1.2 μg.ml-1 and
the stability constant was found to be 3.8x106 L2. mol-2.
The relative standard deviation, recovery and relative error values of method were found to be
R.S.D% = 2.4 , Re % = 96.5 and Erel % = -3.5 . The most important interference were due to Zn2+ ،
Cd2+ ، Hg2+ ، Mg2+ ، Co2+ ، Ag+ ، Pb2+ ، Ca2+ ، CrO4
2- ، Bi3+ ،Ba2+ , WO4
2- ,and Ni2+, and suitable
masking agents were used. The method was applied successfully for determination of copper in the
serum of human blood.