Determination of Cd and Pb in Environmental Samples by Syringe to Syringe Dispersive Liquid Phase Microextration-Solidified Floating Organic Drop Combined Electrothermal Vaporization-Inductively Coupled Plasma Mass Spectrometry

A syringe to syringe dispersive liquid phase microextraction-solidified floating organic drop was induced and used for the ultra-trace simultaneous determination of cadmium and lead after extraction from environmental water samples. The extracted analytes were determined by electrothermal vaporization (ETV)-inductively coupled plasma mass spectrometry (ICP-MS). The analytical parameters affecting the microextraction efficiency including the nature and volume of the extraction solvent, sample volume, pH, ionic strength, concentration of reagents and the cycles of extraction were optimized. The calibration curves were linear in the ranges of 0.01-22.00 ng L-1 and 0.02-25.00 ng L-1 with determination coefficients of 0.9975 and 0.9983 for Cd and Pb, respectively. The limits of detection (LOD) of this method were 0.0017 ng L-1 and 0.00219 ng L-1, and the enhancement factors were estimated to be 342 and 351 for Cd and Pb, and, repeatability (intra-day) and reproducibility (inter-day) were obtained 0.11 and 0.19% for Cd, 0.09 and 0.15% for Pb, respectively. The developed method was successfully applied to determine lead and cadmium in different water samples.