Flow injection determination of bismuth in urine by successive retention of Bi(III) and tetrahydroborate(III) on an anion-exchange resin and hydride generation atomic absorption spectrometry.
ABSTRACT Bismuth as BiCl(4)(-) and BH(4)(-) ware successively retained in a column (150mm x 4mm, length x i.d.) packed with Amberlite IRA-410 (strong anion-exchange resin). This was followed by passage of an injected slug of hydrochloric acid resulting in bismuthine generation (BiH(3)). BiH(3) was stripped from the eluent solution by the addition of a nitrogen flow and the bulk phases were separated in a gas-liquid separator. Finally, bismutine was atomized in a quartz tube for the subsequent detection of bismuth by atomic absorption spectrometry. Different halide complexes of bismuth (namely, BiBr(4)(-), BiI(4)(-) and BiCl(4)(-)) were tested for its pre-concentration, being the chloride complexes which produced the best results. Therefore, a concentration of 0.3moll(-1) of HCl was added to the samples and calibration solutions. A linear response was obtained between the detection limit (3sigma) of 0.225 and 80mugl(-1). The R.S.D.% (n = 10) for a solution containing 50mugl(-1) of Bi was 0.85%. The tolerance of the system to interferences was evaluated by investigating the effect of the following ions: Cu(2+), Co(2+), Ni(2+), Fe(3+), Cd(2+), Pb(2+), Hg(2+), Zn(2+), and Mg(2+). The most severe depression was caused by Hg(2+), which at 60mgl(-1) caused a 5% depression on the signal. For the other cations, concentrations between 1000 and 10,000mgl(-1) could be tolerated. The system was applied to the determination of Bi in urine of patients under therapy with bismuth subcitrate. The recovery of spikes of 5 and 50mugl(-1) of Bi added to the samples prior to digestion with HNO(3) and H(2)O(2) was in satisfactory ranges from 95.0 to 101.0%. The concentrations of bismuth found in six selected samples using this procedure were in good agreement with those obtained by an alternative technique (ETAAS). Finally, the concentration of Bi determined in urine before and after 3 days of treatment were 1.94 +/- 1.26 and 9.02 +/- 5.82mugl(-1), respectively.
- Bulletin of The Chemical Society of Japan - BULL CHEM SOC JPN. 01/2008; 81(2):257-261.
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ABSTRACT: A simple and sensitive flow injection on line separation and preconcentration system coupled to hydride generation atomic fluorescence spectrometry (HG‐AFS) was developed for ultra‐trace bismuth determination in water and urine samples. The preconcentration of bismuth on a nylon fiber‐packed microcolumn was carried out based on the retention of bismuth complex with Bismuthiol I. A 15% (v/v) HCl was introduced to elute the retained analyte complex and merge with KBH4 solution for HG‐AFS detection. Under the optimal experimental conditions, an enhancement factor of 20 was obtained at a sample frequency of 24/h with a sample consumption of 13.0 ml. The limit of detection was 2.8 ng/l and the precision (RSD) for 11 replicate measurements of 0.1 µg/l Bi was 4.4%.Analytical Letters 10/2007; 40(14):2772-2782. · 0.98 Impact Factor
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ABSTRACT: A cloud point extraction process using the nonionic surfactant Triton X-114 to extract bismuth from aqueous solutions was investigated. The method is based on the complexation reaction of Bi(III) with bromopyrogallol red (BPR) and micelle-mediated extraction of the complex. The optimal extraction and reaction conditions (e.g., pH, reagent concentration, effect of time) were studied, and the analytical characteristics of the method (e.g., limit of detection, linear range) were obtained. Linearity was obeyed in the range of 4.60120.0 ng mL-1 of Bi(III) ion. The detection limit of the method was 2.0 ng mL-1 of Bi(III) ion. The interference effect of some anions and cations was also tested. The method was applied to the determination of bismuth in human urine sample.Journal of the Brazilian Chemical Society 01/2006; 17(4). · 1.25 Impact Factor