DETERMINATION OF OXINE-COPPER IN WATER BY GAS-CHROMATOGRAPHY

A gas chromatographic (GC) method for the determination of trace amounts of oxine-copper (Ox-Cu) in water is described. A 500 ml volume of sample water (pH 6.5-6.8) was passed through Sep Pak C18 cartridge at a flowrate of 5 ml/min. Then Ox-Cu absorbed on the cartridge was eluted with 4 ml of methanol. After removing the solvent from the eluate, 2 ml of 0.01 M disodium ethylenediaminetetraacetate solution was added to the residue and the formation of 8-hydroxyquinoline (8-HQ) was facilitated by ultrasonic treatment and vigorous shaking. 8-HQ was extracted twice with 1 ml of benzene and determined with a flame-thermoionic detector (FTD)-GC using a megabore capillary column (DB-1). The recoveries of Ox-Cu from 6 kinds of sample water were 81-97% and the relative standard deviation were 2.5-5.7%. The limit of detection was 0.5-mu-g/l.