ABSTRACT
This work presents a micelle-mediated extraction method for simultaneous preconcentration and determination of Sb(III) and Sb(V) species in biological samples as a prior preconcentration step to their spectrophotometric determination. The analytical system is based on the selective reaction between Sb(III) and bromopyrogallol red (BPR) in the presence of cetyltrimethylammonium bromide (CTAB) and potassium iodide at pH 6.4. Total Sb concentration was determined after reduction of Sb(V) to Sb(III) in the presence of potassium iodide and ascorbic acid. The optimal extraction and reaction conditions were studied and the analytical characteristics of the method (e.g., limit of detection, linear range, preconcentration factor, and improvement factors) were obtained. Linearity for Sb(III) and Sb(V) were obeyed in the range of 0.2-20.0 ng mL(-1) and 0.4-25.0 ng mL(-1), respectively. The detection limit for the determination of Sb(III) and Sb(V) were 0.05 ng mL(-1) and 0.08 ng mL(-1), respectively. The interference effect of some anions and cations was also studied. The method was applied to the determination of Sb(III) in the presence of Sb(V) and total antimony in blood plasma and urine samples.
Subject(s)
Tin Compounds/analysis , Cetrimonium , Cetrimonium Compounds , Coloring Agents , Humans , Hydrogen-Ion Concentration , Indicators and Reagents , Micelles , Pyrogallol/analogs & derivatives , Solutions , Spectrophotometry, Ultraviolet , Surface-Active Agents , Tin Compounds/blood , Tin Compounds/urineABSTRACT
A new micelle-mediated phase preconcentration method for preconcentration of ultra-trace quantities of beryllium as a prior step to its determination by spectrophotometry has been developed. Chrome Azurol S (CAS) and cetyltrimethylammonium bromide (CTAB) were used as chelating agent and cationic surfactant, respectively. The method evaluates and eliminates the blank bias error present in such procedures using mean centering of ratio spectra. This procedure gives more accurate results than the traditional approach using absorbance values against reagent blank. The optimal extraction and reaction conditions were studied and the analytical characteristics of the method (e.g., limit of detection, linear range, preconcentration and improvement factors) were obtained. Linearity was obeyed in the range of 0.9-18.0ngmL(-1) (1.00x10(-7)-2.00x10(-6)molL(-1)) of beryllium. The detection limit of the method is 0.51ngmL(-1) (5.66x10(-8)molL(-1)) of beryllium. The interference effect of some anions and cations was also tested. The method was applied to the determination of beryllium in spring water samples.
ABSTRACT
A new micelle-mediated extraction method for preconcentration of ultra-trace quantities of beryllium and aluminum as a prior step to their simultaneous spectrophotometric determination has been developed. Chrome Azurol S (CAS), cetyltrimethylammonium bromide (CTAB) and Triton X-114 were used as chelating agent, cationic surfactant for extraction and co-extraction agent, respectively. Mean centering (MC) of ratio spectra has been used for simultaneous analysis of beryllium and aluminum. The optimal extraction and reaction conditions were studied, and the analytical characteristics of the method (e.g., limit of detection, linear range, preconcentration, and improvement factors) were obtained. Linearity was obeyed in the range of 5-40ngmL(-1) of beryllium and 3-100ngmL(-1) of aluminum. The detection limit of the method is 0.98 and 0.52ngmL(-1) for beryllium and aluminum, respectively. The interference effect of some anions and cations was also tested. The method was applied to the simultaneous determination of beryllium in water samples.
