Development of on-line single-drop micro-extraction sequential injection system for electrothermal atomic absorption spectrometric determination of trace metals

作者：Anthemidis Aristidis N^*; Adam Ibrahim S I

来源：Analytica Chimica Acta, 2009, 632(2): 216-220.

DOI：10.1016/j.aca.2008.10.078

• Sequential injection
• Single-drop micro-extraction
• Atomic spectrometry
• Metal determination

A novel automatic sequential injection (SI) single-drop micro-extraction (SDME) system is proposed as versatile approach for on-line metal preconcentration and/or separation. Coupled to electrothermal atomic absorption spectrometry (ETAAS) the potentials of this SI scheme are demonstrated for trace cadmium determination in water samples. A non-charged complex of cadmium with ammonium diethyldithiophosphate (DDPA) was produced and extracted on-line into a 60 mu L micro-drop of di-isobutyl ketone (DIBK). The extraction procedure was performed into a newly designed flow-through extraction cell coupled on a sequential injection manifold. As the complex Cd(II)-DDPA flowed continuously around the micro-droplet, the analyte was extracting into the solvent micro-drop. All the critical parameters were optimized and offered good performance characteristics and high preconcentration ratios. For 600s microextraction time, the enhancement factor was 10 and the sampling frequency was 6 h(-1). The detection limit was 0.01 mu g L(-1) and the precision (RSD at 0.1 mu g L(-1) of cadmium) was 3.9%. The proposed method was evaluated by analyzing certified reference material.

• 出版日期2009-1-26