Search

As distinguished from other toxic pollutants, heavy metals can accumulate in living tissues. Among the elements that currently need to be determined in biological samples, chromium is important in view [...], In this study, a simple dispersive liquid--liquid microextraction method based on task-specific ionic liquids was applied for highly sensitive determination and speciation of chromium (III, VI) in human blood by electro-thermal atomic absorption spectrometry. In this method, a mixture containing of 1-(3-aminopropyl)-3-methylimidazolium hexafluorophosphate [APMIM][[PF.sub.6]] and 1-butyl-3-methylimidazolium tetrafluoroborate [BMIM][[BF.sub.4]] (extracting solvent), acetone (dispersant) and TX-100 (anti-sticking agent) were added to Cr(VI) solution in 1 mL blood samples that was extracted by binary mix ionic liquids. For extraction of Cr(VI) anions, the binary mix ionic liquids ([APMIM][[PF.sub.6]], [BMIM][[BF.sub.4]]) and acetone were used as extracting and dispersant solvent, respectively. Total chromium was simply obtained by oxidation of Cr(III) to Cr(VI) by [H.sub.2][O.sub.2] solution, and Cr(III) is calculated by difference between total chromium and Cr(VI). Under the optimal conditions, the calibration graph and limit of detection were 0.02-0.9 µg/L and 5 ng/L, respectively. The developed method was applied successfully to determination and speciation Cr (III, VI) in human blood samples. Keywords: chromium (III, VI), speciation, task-specific ionic liquids, dispersive liquid--liquid microextraction, electro-thermal atomic absorption spectrometry DOI: 10.1134/S1061934815120072