Separative column atomizer for the direct determination of trace amounts of volatile elements by atomic absorption spectrometry

A novel atomizer effective for direct analysis was developed using a new type separative column atomizer (SCA) module. The SCA module incorporated an atomization part, a separation column and/or reaction column part and observation windows for atomic spectroscopic measurement. This module was applied to the direct analysis of trace amounts of mercury and cadmium in practical samples. No background absorption was observed on the thermal decomposition of synthesized samples in a starch matrix and human hair at the wavelengths of the analytical lines of Hg and Cd. The effectiveness of the technique for the determination of elemental compositions is evaluated.     

原子吸收光谱法测定苦藠中微量元素的含量

苦藠别名小野蒜是食用地下鳞茎及嫩茎叶的野生蔬菜,属药食同源的百合科多年生草本植物.有温中散结,宽胸通阳,祛湿止痢作用~([1,2]).在食疗方面有:(1)降脂作用,且性味辛温,能温阳散结,可用来治疗高胆固醇和高血脂症.(2)降低血压的奇妙作用,常食有通阳气、宽胸的效果.     

Application of atomic absorption spectrometry and plasma emission spectrometry to the determination of trace elements in water

Microchimica Acta - The methodology and applicability of two methods for the serial determination of heavy metal traces in water samples is described. Their use within the project of the Deutsche...     

On-line determination of manganese in solid seafood samples by flame atomic absorption spectrometry

Manganese is extracted on-line from solid seafood samples by a simple continuous ultrasound-assisted extraction system (CUES). This system is connected to an on-line manifold, which permits the flow-injection flame atomic absorption spectrometric determination of manganese. Optimisation of the continuous leaching procedure is performed by an experimental design. The proposed method allows the determination of manganese with a relative standard deviation of 0.9% for a sample containing 23.4 μg g⁻¹ manganese (dry mass). The detection limit is 0.4 μg g⁻¹ (dry mass) for 30 mg of sample and the sample throughput is ca. 60 samples per hour. Accurate results are obtained by measuring TORT-1 certified reference material. The procedure is finally applied to mussel, tuna, sardine and clams samples.     

火焰原子吸收光谱法测定软儿梨中微量元素

采用火焰原子吸收光谱法测定了软儿梨果肉和果汁中K、Mg、Fe、Ca、Mn、Cu、Zn的含量.样品以HNO3-HClO4消解,对消解和仪器测定条件进行了优化选择,建立了相应的原子吸收光谱测定方法.方法的RSD在1.0%～3.0%之间,加标回收率在90%～100%之间.     

火焰原子吸收光谱法测定茯苓中微量元素

本文确定了各微量元素火焰原子吸收光谱仪的工作条件,建立了各微量元素线性回归方程.应用火焰原子吸收光谱法测定了天然茯苓和液体发酵茯苓中微量元素含量.研究结果表明二者微量元素含量存在一定的差异,探讨了产生上述差异的原因.     

Procedure for dissolving wolframite in order to determine trace elements by atomic absorption spectrometry

An analytical procedure for dissolving wolframite in order to determine trace elements by atomic absorption is reported. After decomposition of the mineral by alkaline fusion, the cooled flux is dissolved by heating with aqua regia. The finely crystalline precipitate of tungstite, which forms on standing, is filtered and dissolved by heating with aqua regia. Tungstite forms again in the latter solution and the filtration and solubilization are repeated until the solution contains negligible amounts of trace elements. Following this procedure, trace elements in 35 samples of natural wolframite have been dissolved and the solutions obtained have been analyzed by atomic absorption spectrometry for Fe, Mn, Cu, Zn, Pb, Co, Ni and Cd.     

Determination of trace elements in automotive fuels by filter furnace atomic absorption spectrometry

The determination of Cd, Cr, Cu, Pb and Ni was performed in gasoline and diesel fuel samples by electrothermal atomic absorption spectrometry using the Transverse Heated Filter Atomizer (THFA). Thermal conditions were experimentally defined for the investigated elements. The elements were analyzed without addition of chemical modifiers, using organometallic standards for the calibration. Forty-microliter samples were injected into the THFA. Gasoline samples were analyzed directly, while diesel fuel samples were diluted 1:4 with n-heptane. The following characteristic masses were obtained: 0.8 pg Cd, 6.4 pg Cr, 12 pg Cu, 17 pg Pb and 27 pg Ni. The limits of determination for gasoline samples were 0.13 μg/kg Cd, 0.4 μg/kg Cr, 0.9 μg/kg Cu, 1.5 μg/kg Pb and 2.5 μg/kg Ni. The corresponding limit of determination for diesel fuel samples was approximately four times higher for all elements. The element recovery was performed using the addition of organometallic compounds to gasoline and diesel fuel samples and was between 85 and 105% for all elements investigated.     

High performance flow flame atomic absorption spectrometry for interference-free trace determination

In High Performance Flow Atomic Spectrometry (HPF-AS), the aerosol is generated by injecting the sample solution into the gas mixing chamber with the aid of an HPLC pump (Hydraulic High Pressure Nebulization, HHPN, working pressure about 200 bar). Using an additional analytical HPLC column, between sample injection valve and nebulization nozzle, the elements under investigation can be separated from interfering elemental traces or major components (High Performance/Pressure Flow System, HPF). The elements to be determined and the interfering substances reach the flame at different times. This means, for example, that traces of Mg in solutions containing aluminum can be determined without interference. Compared to pneumatic nebulization, there is a 20 fold increase in the detection power when determining calcium in a saturated NaCl solution. HPF-AS is a rapid and sensitive method which allows separation of the calcium from the matrix with subsequent determination in less than 90 s.Dedicated to Professor Dr. Dieter Klockow on the occasion of his 60th birthday     

The determination of trace elements in sulphide minerals by atomic absorption spectrophotometry with absorption tubes

A method for the determination of minor and trace elements (Zn, Cd, Pb, Cu and Ag) in sulphide minerals by atomic absorption spectrophotometry is described. For enhancing the sensitivity of the determination, the absorption tube technique is applied. Memory effects and background absorption influences on the measurement with absorption tubes are discussed.     

原子吸收法间接测定乳制品中乳酸的研究

乳酸作为酸味剂是乳制品的重要成分之一。它是由淀粉接种乳酸菌发酵的产物[1,2],也是判断乳制品质量和新鲜度的重要指标之一。乳酸的测定方法比较常用的有滴定法[2]和液相色谱法[3,4]。平时工作中,乳制品里面存在的大量白色乳浊基体使滴定法难于进行,同时给液相色谱法带来冗长乏味的、复杂的操作步骤。由于共存基体对乳酸测定的严重干扰,用上述方法不能快速、及时地测定日益增加的乳制品的乳酸含量。原子吸收法是测定金属元素的简便、快速、准确的方法。用原子吸收法测定有机化合物已有不少研究[5～11],用原子吸收法测定乳酸的也有报道[…     

On-line determination of trace levels of palladium by flame atomic absorption spectrometry

A preconcentration method is developed for the on-line determination of palladium in complex matrices with flame atomic absorption spectrometry (FAAS). The flow system comprised of a minicolumn filled with polyamine Metalfix-Chelamine resin which is highly selective for Pt(IV), Au(III) and Pd(II). Best preconcentration conditions are established by testing different resin quantities, sample and eluent solution volumes, and adsorption and elution steps flow rates. Sample volumes of 4.7 ml of palladium solutions resulted in an enrichment factor of twenty at the optimum hydrodynamic conditions. This value can be increased by injecting larger volumes of sample solution. The method is sensitive, easy to operate and permitted the determination of sub-mg l⁻¹ levels of palladium with a detection limit of 0.009 mg l⁻¹. The resin was used up to 60 times in consecutive retention-elution cycles without any appreciable deterioration in its performance. The applicability of this method was tested by determining the palladium content in synthetic geological samples as well as in the pellet-type used car catalyst reference material.     

流动注射在线萃取色谱分离原子吸收光谱法测定痕量铂

研究了流动注射在线分离富集原子吸收光谱法测定痕量铂的方法。以自制的GDX501-TBP萃取树脂为微型分离柱，在优化后的分离富集条件下，进样时间为60s，洗脱时间为45s。在线分离测定时间为3min，方法检出限为0．25μg/L，线性范围10—600μg/L，加标回收率为97．8％-103．6％，相对标准偏差3．49％-4．25％。方法已用于矿物管理样中铂的测定。     

微波消解-原子吸收光谱法测定蚕蛹中的微量元素

分别采用FAAS和GFAAS方法,测定蚕蛹样品中的常见微量元素及有害重金属元素。对微波消解条件和测定方法进行了探讨和优化,并用标准物质贻贝验证,获得较满意的准确度和精密度。方法可用于蚕蛹样品及同类产品的微量元素元素测定。     

石墨炉原子吸收光谱法测定大鼠血清中硒

通过考察不同基体改进剂效果,提出了以硝酸锶和硝酸钯做为混合基体改进剂。建立了用石墨炉原子吸收法测定牛血清和大鼠血清中痕量硒的分析方法。线性范围为0-120ng/mL,硒的检出限为0．095ng／mL,方法用于标准牛血清测定。结果与标准值基本吻合,大鼠血清测定标准加入回收率为102％。     

Arsine generation and determination of trace amounts of arsenic by atomic absorption spectrometry

Arsenic can be determined by atomic absorption spectrometry after reduction to arsine with potassium iodide, tin(II) chloride and zinc powder tablet; the arsine generated is carried into an argon-hydrogen flame by means of argon. Accuracy, precision and speed are satisfactory. Serious interferences arise only from nitric acid, lead, chromium and selenium.     

Study on the simultaneous determination of some essential and toxic trace elements in honey by multi-element graphite furnace atomic absorption spectrometry

A multi-element graphite furnace atomic absorption spectrometry (GFAAS) method was elaborated and applied for the simultaneous determination of As, Cd, Cr, Cu, and Pb in various kinds of honey samples (acacia, floral, linden, rape, and milkweed) using the transversally heated graphite atomiser (THGA) with end-capped tubes and integrated graphite platforms (IGPs). For comparative GFAAS analysis, direct (without digestion) and indirect (with digestion in a microwave oven) sample preparation procedures were tested. The effects of several chemical modifiers, such as NH₄H₂PO₄, NH₄H₂PO₄-Mg(NO₃)₂, and Pd(NO₃)₂-Mg(NO₃)₂, were studied to obtain optimal pyrolysis and atomization conditions for the set of analytes studied. The most efficient modifier was proved to be the mixture of 5 μg Pd (applied as nitrate) plus 3 μg Mg(NO₃)₂, allowing the optimal 600 °C pyrolysis and 2300 °C atomization temperatures. To prevent the sputtering and foaming of the matrix during the drying and pyrolysis steps of the furnace heating program, the sample and modifier solutions (20 + 5 μl, respectively) were dispensed together onto the IGP of the THGA pre-heated at 80 °C.The effect of increasing concentration of honey matrix was studied on the integrated absorbance (A_int) signals of analytes. The A_int signals of Cr and Pb were not altered up to 10% (m/v) matrix content in the sample solutions. The matrix effect was slightly suppressive on the A_int signals of As, Cd, and Cu above 2% (m/v) honey concentration. The recovery was found to be ranged between 85 and 115% for Cd, Cr, Cu, and Pb, whereas it was a lower, compromise value of 70-99% for As. The limit of detection (LOD) data were 1, 0.04, 0.09, 0.3, and 0.6 μg l⁻¹ for As, Cd, Cr, Cu, and Pb, respectively, which values correspond to 20, 0.8, 1.8, 5.3, and 12 ng g⁻¹, respectively, in the solid samples. The characteristic masses were found to be 21 pg As, 1.3 pg Cd, 4 pg Cr, 12 pg Cu, and 33 pg Pb. The As, Cd, Cr, Cu, and Pb contents of the studied 42 honey samples varied significantly, i.e. from below the LOD up to 13, 3.3, 109, 445, and 163 ng g⁻¹, respectively.     

Synthesis of amberlite XAD-2-PC resin for preconcentration and determination of trace elements in food samples by flame atomic absorption spectrometry

A new chelating sorbent has been developed using Amberlite XAD-2 resin anchored with pyrocatechol through –N=C– group. This sorbent, characterised by elemental analysis and infrared (IR) spectra, was used as packing for the minicolumn in an on-line system preconcentration system for cadmium, cobalt, copper and nickel determination. Metal ions were sorbed in the minicolumn, from which it could be eluted directly to the nebulizer–burner system of the flame atomic absorption spectrometer (FAAS). Elution of all metals from minicolumn can be made with 0.50 mol L^− 1 HCl or HNO₃. The enrichment factors obtained were 16 (Cd), 24 (Co), 15 (Cu) and 19 (Ni), for 60 s preconcentration time, and 39 (Cd), 69 (Co), 36 (Cu) and 41 (Ni), if used 180 s preconcentration time. Under the optimum conditions, the proposed procedure allowed the determination of cadmium, cobalt, copper and nickel with detection limits of 0.31, 0.32, 0.39 and 1.64 μg L^− 1, respectively, when used preconcentration periods of 180 s. The accuracy of the developed procedure was sufficient and evaluated by the analysis of the certified reference materials NIST 1515 apple leaves and NIST 1570a spinach leaves. The method was applied to the analysis of food samples (spinach, black tea and rice flour).