Determination Of Trace Bismuth Research Articles

Determination of Trace Bismuth in Environmental Waters by ICP‐MS with Cobalt Ion‐Assisted Photochemical Vapour Generation

With increasing use of bismuth in industry, a better understanding of its environmental behaviour is required, including an improved knowledge of its background concentration range in (non‐saline) freshwaters. However, the poor analytical sensitivity of previous methods may lead to inaccurate measurement results for Bi3+ in environmental samples. In this work, cobalt ion‐assisted photochemical vapour generation (PVG) was developed for the detection of trace Bi with inductively coupled plasma‐mass spectrometry (ICP‐MS) measurement. The volatile species of Bi was found to be (CH3)3Bi generated under UV irradiation in the presence of formic acid, acetic acid and Co2+. The major parameters potentially influencing the detection of Bi were investigated. Under optimised conditions, the limit of detection (3s, n = 11) of the proposed method was 0.3 ng l−1. The analytical sensitivity was enhanced about 70‐fold for Bi3+ compared with that using classic pneumatic nebulisation of ICP‐MS. Furthermore, the proposed method showed better analytical sensitivity and anti‐interference ability towards co‐existing ions compared with ferric ion‐assisted PVG systems. The accuracy of the proposed method was evaluated by analysis of environmental water samples and certified reference materials with satisfactory results.

Non-aqueous phase hydride generation and determination of trace bismuth by atomic fluorescence spectrometry

Hydride generation (HG) of bismuth was accomplished in non-aqueous media by using solid reductant of potassium borohydride (KBH4) as a derivation reagent. The riched micelle phase of surfactant Triton X-114 was used as the non-aqueous media for the chemical vapor generation (CVG), and atomic fluorescence spectrometry (AFS) was used for the elemental determination. The analyte ions were firstly extracted into the non-aqueous media from the bulk aqueous phase of analyte/sample solution via a rapid cloud point extraction (RCPE) process and then directly mixed with the solid reductant KBH4 to generate volatile bismuth hydride in a specially designed reactor, which was then rapidly transported to a commercial atomic fluorescence spectrometer for detection. Under the optimal conditions, the limit of detection (LOD) for bismuth was 0.08μg/L. Compared to conventional HG-AFS, the efficiency of non-aqueous phase HG accomplished using solid reductant and the analytical performance of the developed method was considerably improved.

A new supramolecular based liquid solid microextraction method for preconcentration and determination of trace bismuth in human blood serum and hair samples by electrothermal atomic absorption spectrometry.

A simple and reliable supramolecule-aggregated liquid solid microextraction method is described for preconcentration and determination of trace amounts of bismuth in water as well as human blood serum and hair samples. Catanionic microstructures of cetyltrimethylammonium bromide (CTAB) and sodium dodecyl sulfate (SDS) surfactants, dissolved in deionized water/propanol, are used as a green solvent to extract bismuth (III)-diethyldithiocarbamate complexes by dispersive microextraction methodology. The extracted solid phase is easily removed and dissolved in 50μL propanol for subsequent measurement by electrothermal atomic absorption spectrometry (ET-AAS). The procedure benefits the merits of supramolecule aggregates' properties and dispersive microextraction technique using water as the main component of disperser solvent, leading to direct interaction with analyte. Phase separation behavior of extraction solvent and different parameters influencing the extraction efficiency of bismuth ion such as salt concentration, pH, centrifugation time, amount of chelating agent, SDS:CTAB mole ratio, and solvent amounts were thoroughly optimized. Under the optimal experimental conditions, the calibration curve was linear in the range of 0.3-6μgL-1 Bi (III) with a limit of detection (LOD) of 0.16μgL-1 (S/N=3). The relative standard deviations (RSD) of determination were obtained to be 5.1 and 6.2% for 1 and 3μgL-1 of Bi (III), respectively. The developed method was successfully applied as a sensitive and accurate technique for determination of bismuth ion in human blood serum, hair samples, and a certified reference material.

Determination of trace bismuth by using a portable spectrometer after ultrasound-assisted dispersive liquid–liquid microextraction

In this work, ultrasound-assisted dispersive liquid–liquid microextraction (UA-DLLME) was first coupled with a portable tungsten coil electrothermal atomic absorption spectrometer (W-coil ET-AAS) for trace bismuth detection. A conventional disperser solvent in DLLME was substituted by the ultrasound effect, which could afford more effective emulsification and make the extraction method greener. This technique was effectively coupled with a portable W-coil ET-AAS instrument to improve the analytical performance and expand the application of this spectrometer. Under the optimal conditions, the limit of detection (LOD) for bismuth was 0.2 μg L−1, with a sensitivity enhancement factor (EF) of 72. After routine optimization experiments accomplished in the lab, the developed coupling was applied to the field analysis of environmental samples with satisfactory analytical results.

Determination of trace bismuth by under-potential deposition-stripping voltammetry at mesoporous platinum microelectrodes: application to pharmaceutical products

A methodology for the determination of bismuth, based on under-potential deposition-stripping voltammetry (UPD-SV), was investigated. It makes use of mesoporous platinum microelectrodes (Pt-MEs) prepared by a liquid crystal templating technique. The mesoporous microelectrodes, which are characterised by a very high surface area, allowed the accumulation of relatively large amounts of bismuth at under-potential without saturation of the electrode surface. Calibration plots for quantification of bismuth at micromolar levels were constructed by using the charge involved in either the anodic or cathodic peak recoded by cyclic voltammetry that ensued the accumulation of bismuth at the electrode surface. During the anodic scan, the oxidation of metallic bismuth occurred; the cathodic scan involved irreversibly adsorbed bismuth species, which are retained on to the electrode surface. The reproducibility of the proposed UPD-SV procedure (which was within 5 %) was assured by the application to the Pt-MEs of a suitable potential waveform, properly designed to avoid memory effect due to the irreversibly deposited bismuth. The latter phenomenon along with UPD allowed to overcome interference due to copper, which is normally observed when quantification of bismuth is performed by anodic stripping voltammetry at solid electrodes involving bulk metal deposits. The usefulness of the proposed method for the determination of bismuth in real samples was demonstrated by the analysis of a tablet of a pharmaceutical preparation, which is used for curing ulcers.

Determination of Trace Bismuth(III) by Stripping Voltammetry at Antimony-Coated Carbon Paste Electrode

Determination of Trace Bismuth(III) by Stripping Voltammetry at Antimony-Coated Carbon Paste Electrode

Determination of Trace Bismuth in Urine and Tap Water Samples by Atomic Absorption Spectrometry after Solid-Phase Extraction

In this paper, a new method for the determination of bismuth in urine and tap water is described. The methodology combines determined using a hydride generation-atomic absorption spectrometry (HG-AAS) with pre-concentration of the bismuth on the modified organobentonite by dithizone (D-O-bentonite). Optimal experimental conditions for the adsorption and elution of the bismuth, including pH, contact time, eluent concentration, eluent volume and co-existing ions have been investigated. The result showed that the bismuth ion could be adsorbed on the D-O-bentonite. The adsorbed quantitive was affected by the pH value and contact time. In the medium of pH 5.0, the shaking time was 10 min, the adsorption capacity was 15.2 mg·g-1. The bismuth adsorbed on the modified organobentonite by dithizone could be completely eluated by using 2 mol·L-1 HNO3. The method has been applied to the pre-concentration/separation of bismuth in the human urine and tap water samples with satisfied results.

Determination of trace bismuth in human serum by cloud point extraction coupled flow injection inductively coupled plasma optical emission spectrometry

A cloud point extraction method for the preconcentration of ultra-trace bismuth in human serum prior to its determination by inductively coupled plasma optical emission spectrometry had been developed in this paper. The cloud point extraction method was based on the complex of Bi(III) with 8-hydroxyquinoline and Triton X-114 was used as non-ionic surfactant. The main factors affecting cloud point extraction efficiency, such as pH of solution, concentration of complexing agent, concentration of non-ionic surfactant, equilibration temperature and time were investigated in detail. An enrichment factor of 81 was obtained for the preconcentration of Bi(III) with 25 mL solution. Under the optimal conditions, the detection limit of Bi(III) is 0.12 μg L −1. The relative standard deviation ( n = 7) of determination was 2.3%, values of recovery of bismuth were from 92.3% to 94.7% for three samples. This method is simple, accurate, sensitive and can be applied to the determination trace bismuth in human serum.

Determination of Trace Bismuth by a Solid Substrate Room Temperature Phosphorescence Quenching Method Based on Anionic Polymeric Acryclic Acid Lead Particles Containing Luminescent Eosine Molecules

Luminescent particles of Anionic Polymeric Acryclic Acid Lead (Pb(PAA)2) which containing eosine(HFInBr4), Eosine nanomicroball of anionic polypropylene acid lead contained luminophores (short for E.N.PAA.L.C.L), were synthesized by a sol‐gel method, using anionic polymeric acryclic acid sodium (PAANa) as the precursor and Pb2+ as the precipitant. NH4Ac‐HAc can react with the Pb2+ in E.N.PAA.L.C.L, causing it to decompose into aqueous soluble components. E.N.PAA.L.C.L‐ NH4Ac‐HAc can emit strong and stable solid substrate room temperature phosphorescence (SS‐RTP) on filter paper, and bismuth, mercury or iodine can cause a decrease in phosphorescence intensity. Based on the facts above, a new method for the determination of trace bismuth by an SS‐RTP quenching method was established. The linear range of this method was 0.01–0.20(pg spot−1) (4.0×10−12 g ml−1) of Bi3+, with a detection limit (LD) of 0.0016 pg spot−1, and the regression equation of the working curve was ΔIp=61.01+237.8 mBi3+ (pg spot−1), r=0.9992. This method was applied to the determination of trace bismuth in human hair and well water samples with satisfactory results. The mechanism of SS‐RTP emission was also discussed.

Determination of trace bismuth by flow injection-hydride generation collection-atomic absorption spectrometry.

Bismuth hydride gas was collected on-line and determined via a new flow injection-hydride generation collection-flame atomic absorption spectrometry system. The performance of the gas-liquid separator, hydride gas collection time, acidity of the sample solution, NaBH(4) concentration, and the effects of concomitant interferents were investigated to optimize the conditions of this new method. Interferences from concomitant elements were investigated, and recoveries of 94.7-105.3% for 10 ng mL(-1) Bi were obtained after the addition of 0.2% ascorbic acid-thiourea masking reagents. The sensitivity of this new method was one order of magnitude higher than the continuous flow-hydride generation-flame atomic absorption method with a detection limit of 0.25 ng mL(-1) and a precision of 2.3%. The method was evaluated by determining trace bismuth in standard biological reference material human hair GBW07601, and the results were consistent with the certified value. The proposed method was then employed to determine trace bismuth in ten colored gelatin samples; recoveries of 94.2-105.8% were obtained.

Determination of trace bismuth in copper by hydride evolution atomic absorption spectrophotometry

Determination of trace bismuth in copper by hydride evolution atomic absorption spectrophotometry