Determination of cadmium in high salt content matrices by flow injection cold vapor atomic absorption spectrometry

摘要

Flow injection cold vapor atomic absorption spectrometry(FI-CVAAS) was used for determination of cadmium in high salt matricessuch as dialysis concentrates and textile leach solutions. Theparameters such as acidity, concentration of reducing agent, reactioncoil length, and carrier gas flow rate were investigated to obtain thebest sensitivity. No significant background signal was observed evenat high salt concentrations. Under the optimized conditions the limitof detection value (3s_b m^{-1}, where s_b is the standard deviationof the blank signals and m is the slope of the calibration graph) wasfound to be 0.05 ng mL^{-1} for an injection volume of 250 mu L andthe precision in terms of relative standard deviation was 3.2% using11 consecutive measurements of 0.5 ng mL^{-1} standard. The standardaddition method was used for quantitation. The accuracy of the methodwas tested using ETAAS as a comparison method and a certifiedreference material (Waste Water EU-L-1). In both cases, the resultswere in good agreement at 95% confidence level. The concentrationsof cadmium in textile product leach solutions were found to be belowthe limit value assigned by Oeko-Tex standards.