氢化物原子荧光光谱法同时测定生活饮用水中砷和硒

建立了氢化物发生原子荧光光谱法同时测定生活饮用水中砷和硒的方法.测试结果表明砷和硒在质量浓度分别为0.00μg/L~10.00μg/L和0.00μg/L~40.00μg/L范围内呈线性关系,相关系数分别为(砷r=0.9998,硒r=0.9997)。仪器检出限为砷:0.03μg/L硒:0.05μg/L。本方法检出限砷为0.075μg/L;硒为0.125μg/L。水质样品中砷的回收率为92.6%~96.5%,精密度为0.8%~1.4%;硒的回收率为91.2%~97.4%,精密度为1.0%~1.6%。应用本方法测定生活饮用水中的砷和硒方法简便、快速,结果准确可靠,较好地提高了工作效率。     

微波消解-原子荧光光谱法测定中药中的砷和硒

建立了微波消解-原子荧光光谱测定中药中砷和硒含量的方法。该方法测定砷和硒的检出限分别为0.087μg/L和0.123μg/L,荧光强度与砷及硒的质量浓度在0~200μg/L及0~100μg/L范围内呈线性关系。用于中药中砷和硒的测定,相对标准偏差(n=6)均小于3.6%,砷的回收率在95.2%~102.8%之间,硒的回收率在94.5%~104.8%之间。     

原子荧光快速测定环境水样中的砷

本方法采用氢化物-原子荧光方法测定环境水样中的砷,经反复试验证明,本方法是测定环境水样中砷污染的快速、灵敏、具有推广意义的方法。结果表明,本方法检出限为0.07μg/L,相对标准偏差为3.5%,回收率为91%-105%。     

一种自动石墨消解-ICP-MS法监测工业区土壤中微量砷、汞、硒、锑元素残留方法的建立

建立电感耦合等离子体质谱法监测工业区土壤样品中砷、汞、硒、锑4种微量元素残留的分析方法。利用全自动石墨消解仪消解工业园区土壤样品,盐酸-硝酸-氢氟酸体系作为消解酸体系,按照程序设置进行密闭消解,消解液用3%稀硝酸定容,电感耦合等离子体质谱仪定量检测砷、汞、硒、锑4种元素残留量。4种元素质量浓度在0.02～10μg/L范围内线性关系良好,相关系数(r2)0.995;4种元素加标回收率范围为84.5%～107.2%;检出限:砷0.001 8μg/L、汞0.003 4μg/L、硒0.007 4μg/L、锑0.001 0μg/L;精密度相对标准偏差RSD(n=6)在1.35%～3.51%之间,重复性相对标准偏差RSD(n=6)在2.47%～4.89%之间。结果表明,该方法具有前处理快速、检出限低、重复性好、检测结果准确可靠等优点,适用于工业园区土壤中微量元素残留的检测。     

原子荧光光谱法测定蔬菜中微量砷

采用混酸消解样品,通过探讨消化剂、盐酸浓度、硼氢化钾浓度对测定砷的影响,优化实验条件建立了氢化物发生原子荧光法测定中蔬菜微量砷的含量。该方法灵敏简便、快速准确。砷的检出限为0.047μg/L,线性范围0～80μg/L:样品分析结果的相对标准偏差为3.78%,回收率为94.8%～105.2%。     

氢化物—原子荧光法测定饮用水中砷的方法研究与改进

应用氢化物—原子荧光法测定生活饮用水中的砷含量,实验过程中发现绘制的标准曲线和已知浓度水样的测定结果均存在较大误差,通过分析确定起还原剂和掩蔽作用的抗坏血酸在测定过程中存在干扰。在改进方法后,只用硫脲作为还原剂和稳定剂而不加抗坏血酸后测定的标准曲线的线性相关系数为0.9997、检出限为0.035μg/mL,用砷标准溶液6.00μg/L的浓度测得相对标准偏差RSD=2.67%,加标回收率为96.5%-102.5%。实际水样的测定结果也符合国家标准。证明该改进方法对于测定低含量砷且杂质离子未达到影响结果测定浓度时的水样具有过程简单、可靠性强的优点。     

L-半胱氨酸预还原氢化物-原子荧光法测定氧化铜中砷

研究了氢化物发生-原子荧光光谱法测定高含量氧化铜中痕量砷的适宜条件,试验了不同酸介质和还原剂对测定砷的影响。在最佳条件下,砷的线性范围为0.1～40μg/L,检出限为0.075μg/L。样品分析结果的相对标准偏差为2.28%(n=11),加标平均回收率为96.4%。     

氢化物-原子荧光法测定矿泉水中的砷和汞

采用AFS-820双通道原子荧光光度计建立了氢化物—原子荧光法同时测定矿泉水中砷和汞的方法。矿泉水用溴酸钾—溴化钾消解,通过原子荧光法光度计同时测定样品中砷和汞。研究了仪器条件、酸度、KBH4浓度等因素对测定的影响,在最佳工作条件下,砷和汞的检出限分别为0.02μg/L、03μg/L,回收率分别为(95.0~100.5)%(、97.4~105.0)%,相对标准偏差分别为0.98%、0.79%。方法简便、准确、灵敏度高。     

气相-动态顶空进样-气相色谱/质谱法间接测定饮用水源水中苦味酸

建立气相-动态顶空进样-气相色谱/质谱法(D-HS-GC/MS)间接测定饮用水源水中苦味酸(即2,4,6-三硝基苯酚)的方法。基于苦味酸与次氯酸钠反应生成挥发性有机物———氯化苦(硝基三氯甲烷),气相-动态顶空进样技术可对水样液上气相空间的氯化苦进行吹脱捕集,通过气相色谱/质谱法测定氯化苦含量来间接测定苦味酸的浓度。结果表明:苦味酸浓度在1.00²0.0μg/L范围内呈良好的线性关系(r=0.9993),方法检出限为0.40μg/L;1.00,2.50,10.0μg/L标准点测得结果的相对标准偏差(RSD)分别为12.5%、9.2%和10.5%(n=7)。对实际水样进行分析,加标回收率为102%20.0μg/L范围内呈良好的线性关系(r=0.9993),方法检出限为0.40μg/L;1.00,2.50,10.0μg/L标准点测得结果的相对标准偏差(RSD)分别为12.5%、9.2%和10.5%(n=7)。对实际水样进行分析,加标回收率为102%¹31%,RSD为3.5%131%,RSD为3.5%¹6.6%(n=3)。     

阳极溶出伏安法水体镉污染快速测定方法研究

建立一种快速测定水体中镉、铅、汞、砷的阳极溶出伏安法。对现场快速测定影响因素进行探讨,并主要对镉的检出限、精密度和准确度进行研究,将该方法运用到广西龙江镉污染事故应急监测中,并与多种其他方法进行比对。结果表明:该方法运用最优温度为5~40℃,水样最佳p H范围为4~9。便携式阳极溶出伏安法测定污染水样中的镉,检出限为0.1μg/L,加标回收率在80%~110%间;在实际样品质量浓度在2~110μg/L范围内准确度均满足要求,实际样品测定精密度2%~5%;与在线监测结果的相对偏差≤4%,与石墨炉原子吸收测定结果相对偏差≤1%。该方法稳定、快速,灵敏度高,准确度好,可广泛用于重金属污染事故应急监测。     

ICP-MS法同时测定金属包装材料中8种可溶性有害元素

建立了电感耦合等离子体质谱(ICP-MS)法同时测定金属包装材料中砷、钡、镉、铬、铅、锑、硒、汞等8种可溶性有害元素的分析方法,全面考察了消解剂种类及其用量、内标元素的选择及方法的干扰等影响其测量的各种因素,确定了最佳的实验测定条件。方法的检出限为0.03~0.18μg/L,相对标准偏差(RSD)小于5%,加标回收率为87.4%~118.1%。采用该法对金属包装材料实际样品进行了分析,结果表明,此方法简单、准确、重现性好。     

Simultaneous determination of estrogenic short ethoxy chain nonylphenols and their acidic metabolites in water by an in-sample derivatization/solid-phase microextraction method

An in-sample derivatization headspace solid-phase microextraction method has been developed for the simultaneous determination of nonylphenol, nonylphenol mono- and diethoxylates (NP, NP1EO, NP2EO), and their acidic metabolites (NPlEC, NP2EC) in water. The analytical procedure involves derivatization of NPEOs and NPECs to their methyl ethers--esters with dimethyl sulfate/NaOH and further headspace (HS) solid-phase microextraction (SPME) and gas chromatography/mass spectrometry (GC/MS) determination. Parameters affecting both derivatization efficiency and headspace SPME procedure, such as the selection of the SPME coating, derivatizationextraction time, temperature and ionic strength were optimized. The commercially available Carbowax-divinylbenzene (CW-DVB) fiber appears to be the most suitable for the simultaneous determination of both NPEOs-NPECs. Run-to-run precision of the in-sample derivatization/HS-SPME-GC/MS method gave relative standard deviations between 8 and 18%. The method was linear for NP over 2 orders of magnitude, and detection limits were compound dependent but ranged from 20 to 1500 ng/L. The SPME procedure was compared with a solid-phase extraction SPE-GC/MS method for the analysis of NPEOs-NPECs in water samples and good agreement was obtained. Therefore, in-sample derivatization HS-SPME-GC/MS can be used as a method for the simultaneous determination of short ethoxy chain nonylphenols and their acidic metabolites in water.     

Determination of As(III) and total inorganic As in water samples using an on-line solid phase extraction and flow injection hydride generation atomic absorption spectrometry

A simple and robust on-line sequential injection system based on solid phase extraction (SPE) coupled to a flow injection hydride generation atomic absorption spectrometer (FI-HGAAS) with a heated quartz tube atomizer (QTA) was developed and optimized for the determination of As(III) in groundwater without any kind of sample pretreatment. The method was based on the selective retention of inorganic As(V) that was carried out by passing the filtered original sample through a cartridge containing a chloride-form strong anion exchanger. Thus the most toxic form, inorganic As(III), was determined fast and directly by AsH(3) generation using 3.5 mol L(-1) HCl as carrier solution and 0.35% (m/v) NaBH(4) in 0.025% NaOH as the reductant. Since the uptake of As(V) should be interfered by several anions of natural occurrence in waters, the effect of Cl(-), SO(4)(2-), NO(3)(-), HPO(4)(2-), HCO(3)(-) on retention was evaluated and discussed. The total soluble inorganic arsenic concentration was determined on aliquots of filtered samples acidified with concentrated HCl and pre-reduced with 5% KI-5% C(6)H(8)O(6) solution. The concentration of As(V) was calculated by difference between the total soluble inorganic arsenic and As(III) concentrations. Detection limits (LODs) of 0.5 μg L(-1) and 0.6 μg L(-1) for As(III) and inorganic total As, respectively, were obtained for a 500 μL sample volume. The obtained limits of detection allowed testing the water quality according to the national and international regulations. The analytical recovery for water samples spiked with As(III) ranged between 98% and 106%. The sampling throughput for As(III) determination was 60 samplesh(-1). The device for groundwater sampling was especially designed for the authors. Metallic components were avoided and the contact between the sample and the atmospheric oxygen was carried to a minimum. On-field arsenic species separation was performed through the employ of a serial connection of membrane filters and anion-exchange cartridges. Advantages derived from this approach were evaluated. HPLC-ICPMS was employed to study the consistency of the analytical results.     

氢化物发生—原子吸收光谱法测定851口服液中的Se

本文研究了氢化物发生—原子吸收光谱法测定硒的适宜条件,考察了多种离子对硒测定的干扰情况,提出了消除某些过渡金属对硒测定干扰的方法。本方法用于851口服液测定时,对于含硒4μg/L 左右的样品,全程相对标准偏差<14%,加标回收率为93～108%。     

Inorganic selenium speciation in groundwaters by solid phase extraction on Dowex 1X2

A Dowex 1X2 resin separation technique followed by analysis with atomic absorption spectroscopy was evaluated for the study of inorganic selenium speciation in groundwaters. After Se(IV) and Se(VI) were retained on the resin column, Se(IV) and Se(VI) were eluted out by 0.1 and 1M nitric acid solutions. The method detection limit was 5.6 ng/L for both Se(IV) and Se(VI). Analysis of synthetic solutions consistently yielded more than 90% recovery of these two selenium forms with negligible cross-contamination. The results of spiked well waters show that this method can be applied at ultra-trace level of Se in groundwater and the interference of chloride ion can be neglected. Water samples collected from the monitoring wells in the Science-based Industrial Park, Hsin-Chu, Taiwan, were analyzed. Average dissolved selenium concentrations were 32.1+/-17.6 ng/L. The proportion of Se(VI) to the total dissolved selenium ranged from 47.6 to 61.2% and an average of 53.8% in water samples analyzed.     

Simultaneous determination of trace cadmium and arsenic in biological samples by hydride generation-double channel atomic fluorescence spectrometry

Hydride generation atomic fluorescence spectrometry (HG-AFS) has been used for determination of hydride-forming elements because of its high sensitivity, simplicity, and low costs, but most of such work has been concentrated on single element analysis, and reports dealing with multielement determination by HG-nondispersive (ND)AFS are rare. In this work, a sensitive HG-NDAFS method was developed for simultaneous determination of trace cadmium and arsenic in biological materials. The conditions for the generation of volatile cadmium and arsenic species from the reaction with KBH4 in aqueous solution were investigated using a double-channel AFS integrated with an intermittent flow reactor. Like thiourea and Co(II), ascorbic acid was found to significantly enhance the generation efficiency of volatile Cd and As species. The interferences of coexisting ions were evaluated. Under optimal conditions, the detection limits for Cd and As were determined to be 10 and 150 ng L(-1), respectively. The precision for 11 replicate determinations at the 1 microg L(-1) Cd level and the 10 microg L(-1) As level were 3.5 and 2.7% (RSD), respectively. The recoveries of spike analytes in the biological samples studied ranged from 94 to 109%. The proposed method was successfully applied to the simultaneous determination of Cd and As in a variety of biological samples.     

微波消解-电感耦合等离子体质谱(ICP-MS) 同时测定塑料包装材料中有毒有害元素

采用硝酸-过氧化氢消解体系,及高压密闭微波技术处理塑料包装材料,建立了电感耦合等离子体质谱法同时测定塑料包装材料中铅、镉、砷、铬、锑、汞、硒、钡、镍、锡、锶、铊多种有毒有害元素的方法。方法的检出限为0.02~0.20μg/L,相对标准偏差(RSD)小于10%,加标回收率为88.0%~117.0%。该方法简单、快速、灵敏、准确度好。     

Determination of mercury and selenium in herbal medicines and hair by using a nanometer TiO2-coated quartz tube atomizer and hydride generation atomic absorption spectrometry

The nanometer TiO(2) particle was coated onto the inner wall of a T-shaped quartz tube atomizer (QTA) and then was used as a new atomizer (NT-QTA) for the determination of Hg and Se by hydride generation atomic absorption spectrometry (HGAAS). After coating 67.4 mg TiO(2) on a quartz tube, the analytical performance of NT-QTA-HGAAS was compared to conventional QTA-HGAAS and it was improved as follows: (a) the linear range of the calibration curves was expanded from 10.0-80.0 ng mL(-1) to 5.0-150.0 ng mL(-1) for Hg, and from 10.0-70.0 ng mL(-1) to 5.0-100.0 ng mL(-1) for Se; (b) the characteristic concentration of was decreased from 2.8 ng mL(-1)/1% to 1.1 ng mL(-1)/1% for Hg and from 1.2 ng mL(-1)/1% to 0.8 ng mL(-1)/1% for Se; and (c) the interference from the coexistence of As on the determination of Hg and Se could be eliminated. The achieved technique was applied for the determination of Hg and Se in herbal medicines and hair.