Deep eutectic liquid organic salt as a new solvent for carrier-mediated hollow fiber liquid phase microextraction of lead from whole blood followed by electrothermal atomic absorption spectrometry

In the present work, for the first time, a new carrier-mediated hollow fiber liquid phase microextraction (CM-HFLPME) technique was applied for the determination of lead in whole blood samples by means of ETAAS. Lead was extracted from 17 mL of an acidic sample solution into 1-octanol containing N,N,N-cetyltrimethyl ammonium bromide (CTAB) and finally back-extracted into 25 μL of deep eutectic solvent (DES) containing KClO4 as the receiving phase. The effects of different variables on the extraction efficiency were considered using a central composite design. Under the optimized conditions, a preconcentration factor of 33 was obtained. The LOD and LOQ were found to be 0.1 and 0.4 ng mL−1, respectively. The calibration curve was linear within the range of 1–200 ng mL−1 (r2 > 0.9915). RSD% values (n = 3) of 4.4% and 2.3% were obtained at the concentrations of 5.0 and 20 ng mL−1, respectively. Finally, the obtained results for lead contents in two control and test whole blood samples were compared with the lead content of opium samples to investigate the correlation between them.