Separation and determination of gold from iron rich matrices by an off/on-line preconcentration system coupled to ICP-AES

A preconcentration/separation method has been developed for the off/on-line determination by ICP-AES of gold in complex matrices, containing iron and manganese which cause severe spectral interferences on the two most sensitive Au-lines. The available automated preconcentration apparatus was modified using as absorbent the highly selective, for precious metals, chelating anion exchanger SRAFION NMRR. From the elution of this resin with 5% thiourea a nearly quantitative recovery of gold and its separation from iron, existing in percent range in the matrix, and from manganese was obtained. The validity of the developed method was tested by the determination of gold in standard reference materials from BCR, such as sewage sludge of domestic and mainly industrial origin and in a calcareous loam soil. The preconcentration procedure was synchronized with the ICP operating parameters in order to get an optimised on-line coupling of these two systems. The described process has been successfully applied to the determination of low gold contents in dissolved iron rich sediments using for the gold prospection.     

On-line preconcentration and ICP determination for trace metal analysis

The use of a closed-loop on-line enrichment procedure in combination with an ICP plasma emission spectrometer has been developed for the analysis of trace metal ions, such as Cd, Cr, Cu, Fe, Mn, Ni, Pb and Zn. The procedure utilizes a preconcentration column filled with an anion exchange resin and 8-hydroxy-7-iodoquinoline-5-sulphonic acid is added to the sample prior to preconcentration. Details on the optimization of pretreatment and instrumental conditions are described. Results obtained for the analysis of river water and antarctic seawater are reported.Presented in part at the 1989 European Winter Conference on Plasma Spectrochemistry, Reutte, Austria     

High performance ultra trace analysis in molybdenum and tungsten accomplished by on-line coupling of ion chromatography with simultaneous ICP-AES

For the characterisation of trace elements in high purity Mo and W analytical methods with a detection limit in the ng/g-range have to be used. Today mass spectrometric methods are state of the art for such applications. However, these methods in case of refractory metal analysis are time consuming, expensive, limited by isobaric interferences and therefore not very suitable for quality control in an industrial laboratory. With respect to these drawbacks a cost and time efficient method was developed by on-line coupling of an ion chromatographie system to a simultaneous ICP-AES (Inductively Coupled Plasma — Atomic Emission Spectrometry) instrument. Within the limitations caused by the hard- and software of the system all parameters such as eluent concentration and flow rate, nebulizer and plasma gas flow, sampling frequency, integration time and the number of simultaneously measured emission lines were optimised. Further enhancement of the sensitivity was achieved by the use of an ultrasonic nebulizer pushing the detection limits down to the pg/g- and ng/g-range for 22 representative elements.Dedicated to Professor Dr. rer. nat. Dr. h. c. Hubertus Nickel on the occasion of his 65th birthday     

Automatic on line preconcentration and determination of lead in water by ICP-AES using a TS-microcolumn

A simple, sensitive, low-cost and rapid, flow injection system for the on-line preconcentration of lead by sorption on a microcolumn packed with silica gel funtionalized with methylthiosalicylate (TS-gel) was developped. The metal is directly retained on the sorbent column and subsequently then eluted from it by EDTA. Five variables (sample flow rate, eluent flow rate, eluent concentration, pH and buffer concentration) were considered as factors in the optimization process. Interactions between analytical factors and their optimal levels were investigated using two level factorial and Box-Behnken designs. The optimum conditions established were applied to the determination of lead by flow injection inductively coupled plasma atomic emission spectrometry (FI-ICP-AES). The proposed method has a linear calibration range from 10 to at least 500 ng ml⁻¹ of lead. At a sample frequency of 24 h⁻¹ and a 120 s preconcentration time, the enrichment factor was 41, the detection limit was 15.3 ng ml⁻¹ (S/N=3) and the precision, expressed as relative standard deviation, was 0.9% (at 100 ng ml⁻¹). Validation of the developed method was carried out against electrothermal atomic absorption spectrometry analysis without statistically significant differences between the proposed method and the atomic absorption method.     

ICP-AES测定蜂胶中12种元素

采用全谱直读感耦等离子体发射光谱仪测定了蜂胶及蜂胶制品中的12种元素，分析结果表明蜂胶制品中富含多种微量元素。     

ICP-AES连测饲料中的Ca、P、Cr、Cd、Pb、As

应用ICP-AES对饲料中的Ca、P、Cr、Cd、Pb、As的测定进行了研究,确定了合理的测试条件,对微波消解和干法消解样品进行了比较,采用标准物质测定与样品加标回收进行了方法验证。结果表明,微波消解回收率达96%~104%,变异系数小于5%,结果令人满意。该法可同时检测饲料中的多种元素,且精密度高,进样量少,节省试剂,方便快捷。     

Application of chitosan functionalized with 3,4-dihydroxy benzoic acid moiety for on-line preconcentration and determination of trace elements in water samples

Chitosan resin functionalized with 3,4-dihydroxy benzoic acid (CCTS-DHBA resin) was used as a packing material for flow injection (FI) on-line mini-column preconcentration in combination with inductively coupled plasma-atomic emission spectrometry (ICP-AES) for the determination of trace elements such as silver, bismuth, copper, gallium, indium, molybdenum, nickel, uranium, and vanadium in environmental waters. A 5-mL aliquot of sample (pH 5.5) was introduced to the minicolumn for the adsorption/preconcentration of the metal ions, and the collected analytes on the mini-column were eluted with 2 M HNO₃, and the eluates was subsequently transported via direct injection to the nebulizer of ICP-AES for quantification. The parameters affecting on the sensitivity, such as sample pH, sample flow rate, eluent concentration, and eluent flow rate, were carefully examined. Alkali and alkaline earth metal ions commonly existing in river water and seawater did not affect the analysis of metals. Under the optimum conditions, the method allowed the determination of metal ions with detection limits of 0.08 ng mL⁻¹ (Ag), 0.9 ng mL⁻¹ (Bi), 0.07 ng mL⁻¹ (Cu), 0.9 ng mL⁻¹ (Ga), 0.9 ng mL⁻¹ (In), 0.08 ng mL⁻¹ (Mo), 0.09 ng mL⁻¹ (Ni), 0.9 ng mL⁻¹ (U), and 0.08 ng mL⁻¹ (V). By using 5 mL of sample solution, the enrichment factor and collection efficiency were 8–12 fold and 96–102%, respectively, whereas the sample throughput was 7 samples/hour. The method was validated by determining metal ions in certified reference material of river water (SLRS-4) and nearshore seawater (CASS-4), and its applicability was further demonstrated to river water and seawater samples.     

ICP-AES法测定大蒜中的铁、锰、铜、锌、铝和锶等微量元素

用ICP-AES法测定了大蒜中铝、铜、铁、锰、锶和锌等六种微量元素，试验了大蒜样品的分解方法，讨论了钙和磷对测定元素的干扰和溶液酸度对测定结果的影响，并进行了样品分析的精密度和准确度试验。用该法成功地进行了实际样品测定。     

Application of silica gel organofunctionalized with 3(1-imidazolyl)propyl in an on-line preconcentration system for the determination of copper by FAAS

This study presents a new procedure for the determination of trace levels of copper(II) in an aqueous matrix, through flow injection (FI) on-line preconcentration with a minicolumn packed with silica gel modified with 3(1-imidazolyl)propyl groups. After the preconcentration stage, the analyte was eluted with a HNO₃ solution and determined by flame atomic absorption spectrometry (FAAS). The measurements of the analytical signals were carried out as peak area and peak height with the objective of evaluating the most appropriate absorption measurement for the proposed method. Four procedures to calculate the experimental enrichment factor (EF) were also studied. For a preconcentration time of 90 s the enrichment factors found in this study varied between 19.5-25.8 and 36.2-42.2 for peak area and peak height, respectively. The precision of the proposed method was calculated for a solution containing 20 μg l⁻¹ of Cu(II), when 11.2 ml of solution was preconcentrated (n=7), and their respective relative standard deviation (R.S.D.) values were 1.2 and 1.4% for peak area and peak height, respectively. The detection limits obtained were 0.4 and 0.2 μg l⁻¹ of Cu(II) for peak area and peak height, respectively, with a preconcentration time of 90 s. The on-line preconcentration system accuracy was evaluated through a recovery test on the aqueous samples and analysis of a certified material.     

电感耦合等离子体发射光谱法测定二氧化铀中痕量磷和硅元素

研究了电感偶合等离子体发射光谱法测定二氧化铀(UO2)中痕量磷和硅元素含量的方法。经过对HNO3,H2O等试剂的多级纯化,获得超低空白的高纯试剂。对样品溶解、待测杂质元素与铀基体分离等过程从机理方面进行了研究。在分离铀基体与硅元素时用磷酸三丁酯(TBP)作萃取剂,二甲苯作为稀释剂;在分离铀基体与磷元素时用三辛胺(TOA)作萃取剂,二甲苯作稀释剂。二氧化铀中磷、硅元素检出限分别为0.012,0.078μg/g,加标回收率分别为98%,96%,相对标准偏差小于4%(n=6)。该方法重现性好、检出限低,满足生产和科研检测要求。     

An on-line preconcentration/separation system for the determination of bismuth in environmental samples by FAAS

An on-line preconcentration procedure for the determination of bismuth by flame atomic absorption spectrometry (FAAS) has been described. Lewatit TP-207 chelating resin, including iminodiacetate group, packed in a minicolumn was used as adsorbent material. Bi(III) was sorbed on the chelating resin, from which it could be eluted with 3 mol L⁻¹ HNO₃ and then introduced directly to the nebulizer-burner system of FAAS. Best preconcentration conditions were established by testing different resin quantities, acidity of sample, types of eluent, sample and eluent solution volumes, adsorption and elution flow rates, and effect of interfering ions. The detection limit of the method was 2.75 μg L⁻¹ while the relative standard deviation was 3.0% for 0.4 μg mL⁻¹ Bi(III) concentration. The developed method has been applied successfully to the determination of bismuth in pharmaceutical cream, standard reference materials and various natural water samples with satisfactory results.     

Multi-elemental analysis in biological samples by on-line preconcentration on 8-hydroxyquinoline-cellulose microcolumn coupled to simultaneous ICP-AES

Summary The analytical performance of an on-line oxine-cellulose microcolumn preconcentration system coupled to simultaneous ICP was investigated. Different factors including the pH of the sample solution, the flow rates of sample loading and eluation, the acidity of eluent and different eluents were investigated and optimized. In comparison with continuous aspiration, the signal enhancement factors of eleven elements (Zn, Cu, Ni, V, Cr, Fe, Mn, Co, Pb, Cd and Al) were in the range of 6.4 to 13.5 for peak height (0.5 s) and 3.7 to 5.8 for peak area (15 s), respectively. The influences of matrix ions, such as Ca, Mg, Fe, Cu and NaCl were studied. Performance was demonstrated by simultaneous determination of seven (Zn, Cu, Ni, V, Cr, Fe, Mn) elements in a number of CRMs. Most results were satisfactory, except for iron and chromium. The possible reasons were discussed. Co, Pb, Cd and Al were not available in the simultaneous instrument. Therefore, only the analytical performance was measured for these elements by the sequential instrument.On leave from Shanghai Institute of Metallurgy, Academia Sinica, Shanghai, China 200050     

电感耦合等离子体原子发射光谱法在环境分析中的应用

对1996—2010年间电感耦合等离子体原子发射光谱法在环境分析中的应用进展作了评述,主要涉及在大气和飞灰、水、土壤、污泥和植物等方面中的应用(引用文献23篇)。     

ICP-AES法同时测定高纯碘化铯中杂质元素

研究了用ICP-AES法同时测定高纯铯盐中Mn、Mg、Sr、Ca、Ba的方法。在选定的仪器工作参数下，加标回收率达到96％～104％，对合成样品10次重复测定的相对标准偏差〈0．5％，方法简便快捷。     

Sequential-injection on-line preconcentration using chitosan resin functionalized with 2-amino-5-hydroxy benzoic acid for the determination of trace elements in environmental water samples by inductively coupled plasma-atomic emission spectrometry

A new chelating resin using chitosan as a base material was synthesized. Functional moiety of 2-amino-5-hydroxy benzoic acid (AHBA) was chemically bonded to the amino group of cross-linked chitosan (CCTS) through the arm of chloromethyloxirane (CCTS-AHBA resin). Several elements, such as Ag, Be, Cd, Co, Cu, Ni, Pb, U, V, and rare earth elements (REEs), could be adsorbed on the resin. To use the resin for on-line pretreatment, the resin was packed in a mini-column and installed into a sequential-injection/automated pretreatment system (Auto-Pret System) coupled with inductively coupled plasma-atomic emission spectrometry (ICP-AES). The sequential-injection/automated pretreatment system was a laboratory-assembled, and the program was written using Visual Basic software. This system can provide easy operation procedures, less reagent consumption, as well as less waste production.

Experimental variables considered as effective factors in the improvement sensitivity, such as an eluent concentration, a sample and an eluent flow rate, pH of samples, and air-sandwiched eluent were carefully optimized. The proposed system provides excellent on-line collection efficiency, as well as high concentration factors of analytes in water samples, which results in highly sensitive detection of ultra-trace and trace analysis. Under the optimal conditions, the detection limits of 24 elements examined are in the range from ppt to sub-ppb levels. The proposed method was validated by using the standard reference material of a river water, SLRS-4, and the applicability was further demonstrated to the on-line collection/concentration of trace elements, such as Ag, Be, Cd, Co, Cu, Ni, Pb, U, V, and REEs in water samples.     

成年男性精液中19种元素含量的测定及影响因素研究

运用ICP-MS和ICP-AES方法同时分析丹东某硼矿周围工人组及对照组精液中19种元素的含量水平。样品经过双氧水-纯化硝酸体系消解,采用稀释分析及双内标铑(Rh)和铼(Re)进行校正。该法最低检出限、加标回收率及分析精密度能满足精液样品的分析要求。按照95%置信区间进行数据筛选,选出118人的数据统计分析成年男性精液中元素含量水平,并与国内其它研究结果进行比较。分析精液元素含量影响因素表明,硼(B)作业暴露对精液中的B含量具有显著影响;吸烟能显著影响精液中的Cd含量;饮酒对工人组精液中的Cu和Mn的含量具有显著影响。     

内标法在ICP—AES中的应用研究：Ⅱ,应用内标法校正操作参数的变化

本文较系统地研究了ＩＣＰ－ＡＥＳ中可能产生的非随机变化的参数等条件变化时内标元素的选择规则。实验结果表明，在正向功率，载气压力和观察高度变化情况下，分析元素与内标元素的配分函数的匹配最为重要。当分析元素与内标元素的能级分布相似时，可校正操作条件变化对分析准确度的影响。     

ICP-MS/ICP-AES法分析成年男性血清中18种元素含量参照值

运用ICP-MS和ICP-AES法同时分析丹东某硼矿周围人群血清中18种元素的含量水平。样品经过双氧水-纯化硝酸体系消解,采用稀释分析及双内标铑(Rh)和铼(Re)进行校正。该法最低检出限能满足血清样品的分析要求,多数元素回收率在95%~120%之间,相对标准偏差(RSD)在2.9%~10.8%之间。按照95%置信区间进行数据筛选,选出125人的数据统计分析,并与国内外其它研究结果进行比较。结果表明,采用该方法对血清中元素的分析结果可以作为当地成年男性血清中元素含量的参照值。     

正交试验在原油重金属元素测定中的应用

采用微波消解技术,以ICP-AES同时测定原油中V、Ni、Mn、Pb重金属元素的含量。该方法回收率在94.73%～107.2%之间,相对标准偏差小于2.12%,适用于原油中各种重金属元素的测定。采用正交设计法安排实验,可以以少量的实验次数获得大量信息,既节省时间又节约药品。同时利用原油样品中的V/Ni的比值作为参数,可判断原油油源的特征及地质特点。     

Sensitivity enhancement of capillary electrophoresis-frontal analysis-based method for characterization of drug-protein interactions using on-line sample preconcentration

Capillary electrophoresis-frontal analysis is one of the most frequently used approaches for the study of plasma protein-drug interactions as a substantial part of new drug development. However, the capillary electrophoresis-frontal analysis typically combined with ultraviolet-visible detection suffers from insufficient concentration sensitivity, particularly for substances with limited solubility and low molar absorption coefficient. The sensitivity problem has been solved in this work by its combination with an on-line sample preconcentration. According to the knowledge of the authors this combination has never been used to characterize plasma protein-drug binding. It resulted in a fully automated and versatile methodology for the characterization of binding interactions. Further, the validated method minimalizes the experimental errors due to a reduction in the manipulation of samples. Moreover, employing an on-line preconcentration strategy with capillary electrophoresis-frontal analysis using human serum albumin-salicylic acid as a model system improves the drug concentration sensitivity 17-fold compared to the conventional method. The value of binding constant (1.51 ± 0.63) · 10⁴ L/mol obtained by this new capillary electrophoresis-frontal analysis modification is in agreement with the value (1.13 ± 0.28) ·10⁴ L/mol estimated by a conventional variant of capillary electrophoresis-frontal analysis without the preconcentration step, as well as with literature data obtained using different techniques.