石墨炉原子吸收法测定洗涤剂中砷含量

建立了石墨炉原子吸收光谱法测定洗涤剂中砷含量的方法。采取硝酸及高氯酸法处理样品,加入基体改进剂硝酸镍,应用石墨炉原子吸收光谱法测定砷。结果表明,测定一次回归方程为Y=0.0012X+0.0009,相关系数r=0.9994。检出限为0.16 ug/L,回收率为92.9%～101.4%,相对标准偏差为1.42%～3.18%。该方法具有快速、准确、灵敏度高等优点,适用于洗涤剂中砷含量的检测。     

微波消解-石墨炉原子吸收法测定纸巾纸中砷含量

建立了石墨炉原子吸收光谱法测定纸巾纸中砷含量的方法。采用微波消解技术处理样品,加入基体改进剂硝酸镍,应用石墨炉原子吸收光谱法测定砷。结果表明,测定一次回归方程为Y=0.0025X+0.0004,相关系数r=0.9996。检出限为0.12 ug/L,回收率为95.8%～100.3%,相对标准偏差为2.37%。该方法具有快速、准确、灵敏度高等优点,适用于纸巾纸中砷含量的检测。     

甲苯萃取-GFAAS法测定高盐食品中微量砷

建立甲苯萃取-石墨炉原子吸收测定高盐食品中砷的方法。用微波消解样品,甲苯萃取分离砷,硝酸镍作基体改进剂,钯涂层石墨炉原子吸收法测定高盐食品中微量砷。结果表明:用甲苯萃取砷提高了回收率,很好地消除基体干扰;用硝酸镍作基体改进剂,提高砷的灰化温度和灵敏度,方法的相对标准偏差≤1.12%(n=6);回收率达到97.5%~104.5%;检出限为0.038 mg/kg。该法灵敏、准确、可靠,可用于高盐食品中微量砷的测定。     

石墨炉原子吸收光谱法测定金银花中铅镉的研究

采用石墨炉原子吸收法(GFAAS)检测中药材金银花中微量重金属铅、镉的含量.考察了基体改进剂、灰化/原子化温度和常见共存离子等因素对测定的影响,建立以NH4H2PO4为基体改进剂石墨炉原子吸收光谱法测定金银花中微量铅、镉的方法.条件优化后的方法简便快速,重现性好,灵敏度、准确度高,铅的检出限为0.268 μg/L,镉的检出限为0.013 μg/L,回收率85%～110%.     

微波消解-石墨炉原子吸收光谱法测定纳米二氧化钛中痕量砷

建立微波消解-石墨炉原子吸收光谱法(GF-AAS)测定纳米二氧化钛中痕量杂质砷的分析方法,以快速完全消解二氧化钛基体并且准确测定痕量杂质砷。方法采用氢氟酸、硝酸混合试剂结合高压密闭微波加热技术,解决二氧化钛难消解和低酸度溶液中高钛基体容易水解等难点。通过基体效应影响试验,优选采用热解涂层石墨管,优化石墨炉升温原子化控制程序以及原子吸收光谱仪工作条件等检测参数,消除热稳定性强的二氧化钛基体对测定易挥发痕量元素砷的影响。结果表明:方法检出限为0.02μg/L,回收率为93.0%~106.0%,相对标准偏差9.36%,与ICP-MS检测方法结果对照一致。     

混合基体改进剂消除GFAAS法测定补钙食品中镉干扰的研究

采用石墨炉原子吸收测定补钙食品中镉含量。用仪器自动进样器,分别加入基体改进剂:磷酸二氢铵、氯化钯和磷酸二氢铵-氯化钯。测定不同钙离子浓度条件下镉的吸光度,并比较它们消除干扰的程度。根据测定的回收率,确定使用磷酸二氢铵氯化钯混合基体改进剂消除钙对镉的干扰较为理想。使用此法,实际样品回收率和精密度得到改善,标准物质分析结果令人满意。     

石墨炉原子吸收中胶体钯基改剂消除土壤样品复杂基质干扰的研究

本文应用新型基改剂胶体钯为基体改进剂,采用石墨炉原子吸收测定基体复杂土壤样品中的镉,详细研究了不同基改剂对基体的影响,克服了复杂样品基质的干扰,建立了适合土壤中镉的分析方法,该方法简单、快速、准确。     

微波消解-石墨炉原子吸收光谱法测定蔬菜中痕量钼

建立了微波消解-石墨炉原子吸收光谱法测定蔬菜样品中的痕量钼。通过密闭高压、微波消解样品来制备样品溶液,研究了不同基体改进剂及其用量对吸光度的影响;采用氘灯背景扣除,313.3 nm作为钼的测定波长,3μL 1 g·L~(-1)磷酸二氢铵为基体改进剂,灰化温度为1000℃;原子化温度为2800℃。在该实验条件下,方法的线性范围为0~200μg·L~(-1),相关系数r=0.9997,检出限为3.6μg·L~(-1),测定样品的相对偏差为0.50~2.1%,回收率为92.8%~102.4%。该法灵敏快速,准确度高,适用于蔬菜等植物样品中痕量钼的测定。     

塞曼石墨炉原子吸收分光光度法测定水中痕量银

1概述银是国家生活饮用水卫生标准的重要毒理性指标,其最高允许浓度为50μg/L。本文建立的石墨炉原子吸收分光光度法测定水中的痕量银,用塞曼效应扣除背景干扰,优化了石墨炉升温程序,样品不需消化处理,不使用基体改进剂,缩短了分析时间,减少了试剂沾污,方法简单、快速。本法银的最低检测浓度为0.10μg/L,适用于测定生活饮用水及水源中水痕量银。2方法原理本法基于样品注入石墨管中,所含银离子在石墨管内高温蒸发解离为原子蒸气,并吸收银空心阴极灯发射的共振线(328.1nm),且其吸收强度在一定范围内与银浓度成正比。因此,可在其他条件不变的…     

石墨炉原子吸收法测定金属过程中常用基体改进剂效用分析

石墨炉原子吸收法在测定基体复杂的样品时,背景干扰相当严重,本文从无机试剂、有机试剂、活性气体等三个方面探讨了目前常用的各种基体改进剂在元素测定过程中的效用。     

Trace analysis of antidepressant pharmaceuticals and their select degradates in aquatic matrixes by LC/ESI/MS/MS

Treated wastewater effluent is a potential environmental point source for antidepressant pharmaceuticals. A quantitative method was developed for the determination of trace levels of antidepressants in environmental aquatic matrixes using solid-phase extraction coupled with liquid chromatography-electrospray ionization tandem mass spectrometry. Recoveries of parent antidepressants from matrix spiking experiments for the individual antidepressants ranged from 72 to 118% at low concentrations (0.5 ng/L) and 70 to 118% at high concentrations (100 ng/L) for the solid-phase extraction method. Method detection limits for the individual antidepressant compounds ranged from 0.19 to 0.45 ng/L. The method was applied to wastewater effluent and samples collected from a wastewater-dominated stream. Venlafaxine was the predominant antidepressant observed in wastewater and river water samples. Individual antidepressant concentrations found in the wastewater effluent ranged from 3 (duloxetine) to 2190 ng/L (venlafaxine), whereas individual concentrations in the waste-dominated stream ranged from 0.72 (norfluoxetine) to 1310 ng/L (venlafaxine).     

应用AFS—930型双道原子荧光光度计联合测定水中的砷和硒

本文采用原子荧光光谱法,研究了联合测定水样中砷和硒的技术。用10%盐酸和1%硫脲-1%抗坏血酸混合试剂处理样品,并以2.0%硼氢化钾和0.5%氢氧化钠为还原剂,在5%的盐酸介质测定砷和硒。砷和硒的检出限分别为:0.20μg/L和0.13μg/L,本方法具有操作简便、快速、基体干扰少、灵敏度高等优点,可用于水样中砷和硒的联合测定。     

Analysis of acrylamide in water using a coevaporation preparative step and isotope dilution liquid chromatography tandem mass spectrometry

Acrylamide is a probable human carcinogen, and the drinking water quality guideline for this compound is 0.5 mg/L. However, analysis of this compound in water is difficult because of its very high water solubility, which limits the efficiency of sample preconcentration prior to analysis. We developed a robust and sensitive analytical method for the determination of trace quantities of acrylamide in samples of water using a novel preparative technique and isotope dilution liquid chromatography tandem mass spectrometry with atmospheric pressure chemical ionization as the ion source (LC-APCI-MS/MS). The preparative method involves coevaporation of acrylamide with water at pH 10 using a rotary evaporator, followed by acidification to pH 3.0 and concentration of the sample prior to analysis by LC-APCI-MS/MS. To compensate for the loss of the analyte during sample preparation and signal suppression due to interference from the sample matrix, isotope dilution with acrylamide-d3 was used for quantitation. Using this method, analyte recoveries ranged from 74 to 103% for acrylamide spiked into water at a concentration of 0.4 ng/mL. The limit of detection and limit of quantification (LOQ) for acrylamide in water were 0.02 and 0.06 ng/mL, respectively. This method was successfully applied to determine trace levels of acrylamide in samples of river water and in runoff from an agricultural field to which municipal biosolids (i.e., sludge) had been applied. Concentrations of acrylamide in these samples ranged from 相似文献   

微波辅助萃取/分光光度法快速测定抗菌纺织品中的三氯生

为了测定抗菌纺织品中三氯生的含量,本文以二氯甲烷为萃取溶剂,采用微波萃取技术萃取抗菌纺织品中的抗菌剂三氯生。萃取液蒸发至干后,用甲醇定容,然后以甲醇为参比溶液,在282nm波长下测定其吸光度,从而建立了一种测定抗菌纺织品中的抗菌剂三氯生的分光光度方法,并对萃取条件、方法的线性关系、精密度、回收率、检出限等进行了研究。三氯生在0.2-80mg/L范围内呈现良好的线性关系,线性相关系数为0.9998,回收率为91.98%-104.94%,相对标准偏差均小于6%,检出限为0.1mg/kg(S/N=3)。采用该方法对市售抗菌纺织品进行检测,发现部分抗菌纺织品中使用高含量的三氯生。     

柠檬酸-硝酸作基体改进剂石墨炉原子吸收法测定水中的铯

本文提出了以柠檬酸—硝酸作为基体改进剂,石墨炉原于吸收法测定水中的铯,系统地研究了 Cs 的实验条件,重点探讨了基体改进剂的选择及干扰的消除。该法特征量为22pg,检出限(3S)为0.93ng/mL,方法简便、快速、准确。本法应用于实际样品的分析,获得满意的结果,可满足水质分析的要求。     

Trace analysis of trimethoprim and sulfonamide, macrolide, quinolone, and tetracycline antibiotics in chlorinated drinking water using liquid chromatography electrospray tandem mass spectrometry

A multirun analytical method has been developed and validated for trace determination of 24 antibiotics including 7 sulfonamides, 3 macrolides, 7 quinolones, 6 tetracyclines, and trimethoprim in chlorine-disinfected drinking water using a single solid-phase extraction method coupled to liquid chromatography with positive electrospray tandem mass spectrometry detection. The analytes were extracted by a hydrophilic-lipophilic balanced resin and eluted with acidified methanol (0.1% formic acid), resulting in analyte recoveries generally above 90%. The limits of quantitation were mostly below 10 ng/L in drinking water. Since the concentrated sample matrix typically caused ion suppression during electrospray ionization, the method of standard addition was used for quantitation. Chlorine residuals in drinking water can react with some antibiotics, but ascorbic acid was found to be an effective chlorine quenching agent without affecting the analysis and stability of the antibiotics in water. A preliminary occurrence study using this method revealed the presence of some antibiotics in drinking waters, including sulfamethoxazole (3.0-3.4 ng/L), macrolides (1.4-4.9 ng/L), and quinolones (1.2-4.0 ng/L).     

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.     

Bioinspired Janus Textile with Conical Micropores for Human Body Moisture and Thermal Management

Excessive sweat secreted from the skin often causes undesired adhesion from wetted textiles and cold sensations. Traditional hydrophilic textiles such as cotton can absorb sweat but retain it. A hydrophobic/superhydrophilic Janus polyester/nitrocellulose textile embedded with a conical micropore array with a hydrophilic inner surface that can achieve directional liquid transport (with an ultrahigh directional water transport capability of 1246%) and maintain human body temperature (2–3 °C higher than with cotton textiles) is demonstrated. When the hydrophobic polyester layer with large opening of hydrophilic conical micropores contacts the liquid, the Janus polyester/nitrocellulose textile can pump it to the superhydrophilic nitrocellulose layer through the hydrophilic conical micropores driven by capillary force. The Janus polyester/nitrocellulose textile can weaken undesired wet adhesion and heat loss due to the removal of liquid. The water wicking and air permeability of the Janus polyester/nitrocellulose textile is comparable to those of traditional cloths. This study is valuable for designing of functional textiles with directional water transport properties for personal drying and warming applications.     

Determination of trace perchlorate in high-salinity water samples by ion chromatography with on-line preconcentration and preelution

A simple, automated system for the determination of trace perchlorate by ion chromatography (IC) with an online preconcentration technique is reported. The sample is preconcentrated, and less strongly held ions preeluted before the analyte is transferred to the principal separation system. This approach provides low limits of detection (LOD) and is particularly robust toward the effect of high concentrations of common anions, such as those present in groundwater samples. It compares favorably with currently promulgated EPA method 314.0. The LOD (S/N = 3) is 0.77 microg/L for a 2-mL reagent water sample and decreases more-or-less proportionately with increasing sample volume, at least up to 20 mL. Even with a sample of conductivity 14.7 mS/cm (approximately that of 0.1 M Na2SO4), the recovery of added perchlorate at the 25.0 microg/L level was still 92%. The concentration of added perchlorate in the range of 1-400 microg/L was linearly correlated to the peak area, with an r2 value of 0.9997. The recovery of perchlorate from artificial samples with different conductivity by the present method compares favorably with those from the currently recommended EPA Method. The ability of this approach to remove matrix interferences suggests that it would be also promising for perchlorate analysis in other challenging samples.