Determination of trace bismuth by using a portable spectrometer after ultrasound-assisted dispersive liquid-liquid microextraction

In this work, ultrasound-assisted dispersive liquid-liquid microextraction (UA-DLLME) was first coupled with a portable tungsten coil electrothermal atomic absorption spectrometer (W-coil ET-AAS) for trace bismuth detection. A conventional disperser solvent in DLLME was substituted by the ultrasound effect, which could afford more effective emulsification and make the extraction method greener. This technique was effectively coupled with a portable W-coil ET-AAS instrument to improve the analytical performance and expand the application of this spectrometer. Under the optimal conditions, the limit of detection (LOD) for bismuth was 0.2 mu g L-1, with a sensitivity enhancement factor (EF) of 72. After routine optimization experiments accomplished in the lab, the developed coupling was applied to the field analysis of environmental samples with satisfactory analytical results.