Catalytic determination of ultra trace amounts of titanium by 2.5 - order differential oscillopolarography

Ti(IV) has a very strong catalytic effect on the slow reaction of iodate-io dide-brilliant green (BG) in diluted sulphuric acid medium at 100 degreesC. Brilliant green exhibits a sensitive 2.5 order differential oscillopolarog raphic wave at -0.45V(Vs.SCE.). The influence of excess IO3- on the polarog raphic measurements of Brilliant green can be eliminated by addition of asc orbic acid. This provides the basis for a novel and highly sensitive and se lective catalytic kinetic method with 2.5 order differential oscillopolarog raphic detection of titanium. The effects of sulphuric acid, potassium ioda te, potassium iodide and Brilliant green concentrations, reaction temperatu re and reaction time have been investigated. A calibration curve of titaniu m in the range 0.1 to 10.0 ng ml(-1) has been obtained by the fixed-time pr ocedure. The detection limit is found to be 0.03 ng ml(-1). The new method has been applied for the determination of trace amounts of Ti in hair sampl es with satisfactory results.