Preconcentration of ultra-trace copper in water samples with nanometer-size TiO2 colloid and determination by GFAAS with slurry sampling

A method is presented for the preconcentration of Cu(II) ions using a nanometer-sized TiO2 colloid, and for their determination in environmental water using graphite furnace atomic adsorption spectrometry (GFAAS) with slurry sampling. The adsorption efficiency is above 97% and is reached within short time at pH values between 5.5 and 6.0. Cu(II) was determined by GFAAS without elution. Conditions such as colloid dosage and effects of other ions were studied. The detection limit (3 σ) and the relative standard deviation are 290 ng L-1 and 9.8% (n = 6), respectively. This simple and rapid method was successfully applied to spiked environmental samples with recoveries ranging from 97% – 104%.