土壤中铅的分析方法比对

对不同的样品消解方法及电感耦合等离子体质谱、电感耦合等离子体原子发射光谱、石墨炉原子吸收光谱法测定土壤中铅的测定结果进行比对。采用电热板、微波及水浴3种加热方式,选择硝酸、氢氟酸、双氧水、王水、高氯酸、盐酸的不同组合进行土壤样品消解,通过分析测定值的精密度和准确度,考察消解体系对电感耦合等离子体质谱、电感耦合等离子体发射光谱、石墨炉原子吸收光谱法测定结果的影响。结果表明采用电感耦合等离子体质谱法测定土壤中的铅,最适宜的消解体系是硝酸-氢氟酸-高氯酸(微波加热),采用电感耦合等离子体原子发射光谱法测定最适宜的消解体系是硝酸(电热板加热),采用石墨炉原子吸收光谱法测定最适宜的消解体系是硝酸-盐酸-高氯酸(微波加热)。电感耦合等离子体质谱法的精密度和准确度优于另外两种方法。     

GFAAS和ICP-MS对比测定大米中三种重金属含量

分别采用石墨炉原子吸收光谱法(GFAAS)与电感耦合等离子体质谱法(ICP-MS)同时测定大米中铅、镉和铬三种重金属含量,从分析方法的准确度、精密度等方面比较两种方法的优缺点。研究结果表明,两种方法测定结果均能满足分析要求,但ICP-MS法的测定结果更接近样品真实值,操作更加简便。     

电感耦合等离子体发射光谱法测定地质样品中的钨、钼、锡

改进了电感耦合等离子体发射光谱法(ICP-AES)同时测定多金属矿石等地质勘查样品中钨、钼、锡的溶样方法。采取酸溶和碱熔结合,先用硝酸和高氯酸及氢氟酸溶样,用盐酸(1+1)浸取再过滤,滤渣及滤纸灰化后再碱熔,最后用电感耦合等离子体发射光谱法(ICP-AES)测定钨、钼、锡。克服了传统的酸溶法导致锡的测定结果偏低和碱熔法易堵塞ICP-AES矩管和雾化器的两大弊端,方法经国家一级标准物质验证,精密度和准确度均能达到日常分析的要求。     

微波等离子体原子发射光谱法测定交联淀粉中磷含量

采用微波等离子体原子发射光谱法,以氩气为工作气体和载气,氧气为屏蔽气,测定了交联淀粉中磷含量.试验表明:测试溶液的酸度应保持在0.03 mol·L-1以下,且预先将样品充分洗涤,除去共存的钠离子.在最佳试验条件下测定了磷的检出限、精密度、加标回收率.结果表明:波长为253.565 nm的分析谱线具有最高的灵敏度;载气和工作气为氩气,流量分别为1.5,0.27 L·min-1时,分析线253.565 nm的强度最高.测得磷的检出限(3S/N)为0.02μg·L-1.此方法测得结果的准确度和精密度与电感耦合等离子体原子发射光谱法相当,而从节能和降低成本方面考虑此方法有更好的应用前景.     

电感耦合等离子体发射光谱法测定植物油中的磷

用电感耦合等离子体发射光谱法(ICP-AES)测定了植物油中的磷.采用多谱线拟合技术(MSF)校正了铜对P213.617 nm和P214.914 nm光谱干扰.比较了活性炭炭化灰化法和微波消解法两种样品前处理方法对分析结果的影响.结果表明这两种前处理方法所得结果都能与国标磷钼蓝分光光度法的分析结果吻合,其中活性炭炭化灰化法的方法检出限(0.053 mg/kg)较微波消解法的方法检出限(0.42 mg/kg)更低,所以对低含量的磷的检测结果其相对误差及精密度更好.该法应用于植物油中磷的测定.     

电感耦合等离子体原子发射光谱(ICP-OES)法测定地球化学样品中的铁

试样用HCl和HNO3分解,制成含2%~3%王水的样品溶液,在最佳条件下,用电感耦合等离子体原子发射光谱(ICP-OES)法测定样品中铁的含量。方法相对标准偏差RSD(n=12)为0.41%~1.6%,精密度和准确度均符合地质矿产实验室测试质量管理规范(区域地球化学普查样品化学成分分析)要求。适用于地球化学调查样品批量样品中铁的测定,方法已应用于实际工作中,结果满意。     

电感耦合等离子体发射光谱法测定电厂煤灰中常量元素

采用四硼酸锂-硼酸对样品进行熔融、电感耦合等离子体发射光谱法测定电厂煤灰样品中常量元素,与国家标准方法(GB/T 1574-1995)比较,方法简便,测定结果准确度高,11种元素的相对标准偏差均小于2%.     

化学浸提-电感耦合等离子体发射光谱法测定粉条中活性铝的化学形态

采用化学浸提-电感耦合等离子体发射光谱法(ICP-OES)测定粉条中溶出铝的化学形态及其含量.实验结果显示,粉条溶出铝中,Al3+为135 μg/g,Al(OH)2+和Al(OH)2-未检出,胶态Al(OH)3o为143 μg/g,有机铝为460 μg/g.各化学形态铝含量的回收率在88.3％～105％范围,精密度(RSD)为1.14％,方法检出限为0.74 mg/kg.该方法准确度高,精密度好,检出限低,线性关系好,是一种简便实用的食品、药物中活性铝化学形态的检测方法.     

电感耦合等离子体原子发射光谱法测定柑橘中镧系元素含量

应用电感耦合等离子体发射光谱法同时测定柑橘中的5种稀土元素镧、铈、镨、钕和钐.对分析线选择、积分时问的选择、消解方法的选择、介质的影响等进行了试验.与干灰化法相比较,微波消解法处理样品所得结果的准确度和精密度更好.选择波长为333.749,418.660,390.844,415.608及359.260 nm 5条谱线依次作为测定镧、铈、镨、钕和钐的分析线,测得5种稀土元素的检出限(3s/k)依次为0.003 3,0.017 0,0.014 0,0.039 0及0.007 8 mg·L-1.应用此法测定了沙田柚中5种稀土元素的含量,回收率在96.8%～101.0%之间,相对标准偏差(n=5)小于5.5%.与GB/T 5009.94-2003法比较,经t检验,在置信水平α=0.05时,测定沙田柚时两种方法无显著性差异.     

电感耦合等离子体原子发射光谱法测定玻璃澄清剂中砷的前处理方法研究

研究了几种常规前处理方法对玻璃澄清剂中砷测定的影响,建立了一种预氧化处理、后酸式湿分解的前处理方法.较传统碱熔法而言,该方法简单方便且可操作性强,同时可避免传统酸溶分解过程中可能造成的砷挥发损失.对预氧化处理使用的氧化剂和预氧化过程进行了筛选与优化,确定了4种湿式预氧化-酸消化分解方法,并利用端视电感耦合等离子体发射光谱实现了砷的直接测定.通过精密度和准确度实验,得到4种方法的相对标准偏差均小于2%,样品的加标回收率为98% ～106%,表明该前处理方法准确度高、精密度好.将所建立的分析方法用于玻璃澄清剂样品的测定,结果令人满意.     

Multiresidue determination of quinolones regulated by the European Union in bovine and porcine plasma. Application of chromatographic and capillary electrophoretic methodologies

This paper presents the multiresidue determination of the series of quinolones regulated by the European Union (marbofloxacin, ciprofloxacin, danofloxacin, enrofloxacin, sarafloxacin, difloxacin, oxolinic acid and flumequine) in bovine and porcine plasma using capillary electrophoresis and liquid chromatography with ultraviolet detection (CE‐UV, LC‐UV), liquid chromatography–mass spectrometry and –tandem mass spectrometry (LC‐MS, LC‐MS/MS) methods. These procedures involve a sample preparation by solid‐phase extraction for clean‐up and preconcentration of the analytes before their injection into the separation system. All methods give satisfactory results in terms of linearity, precision, accuracy and limits of quantification. The suitability of the methods to determine quinolones was evaluated by determining the concentration of enrofloxacin and ciprofloxacin in real samples from pig plasma and cow plasma. Copyright © 2010 John Wiley & Sons, Ltd.     

Determination of Metals in Fruits of Cucurbitaceae Species from South Korea,to Characterize Potential Effects on Human Health

Recent research studies have confirmed that the dietary intake of vegetables and fruits has a positive and profound impact on human health, performance, and disease. This research was designed to determine the concentrations of essential trace elements; cobalt (Co), chromium (Cr), copper (Cu), manganese (Mn), selenium (Se), vanadium (V), and zinc (Zn), toxic metals; cadmium (Cd), mercury (Hg), and lead (Pb); and a metalloid; arsenic (As) in fruits of seven species of Cucurbitaceae family including gourd, zucchini, pumpkin, sweet pumpkin, melon, watermelon, and oriental melon commonly consumed in South Korea. The concentrations of As, Cd, Co, Cr, Cu, Pb, Se, and Zn were determined using inductively coupled plasma mass spectrometry, and Hg by a mercury analyzer. To analyze the samples after microwave digestion for the validation of analytical techniques, satisfactory values of all quality parameters of linearity, detection limits, precision, accuracy, and recovery experiments were obtained in all cases. On the whole, all analyzed elements were found in accordance to the published literature around the world and well within the critical recommended standards by CODEX and Ministry of Food and Drug Safety, Korea. The estimated daily intake values, and hazard quotients and indices of the analyzed samples were all below the World Health Organization, Joint Food and Agriculture Organization/World Health Organization Expert Committee on Food Additives, and European Food Safety Authority limits.     

Comparison of gas chromatographic hyphenated techniques for mercury speciation analysis

In this study, we evaluate advantages and disadvantages of three hyphenated techniques for mercury speciation analysis in different sample matrices using gas chromatography (GC) with mass spectrometry (GC-MS), inductively coupled plasma mass spectrometry (GC-ICP-MS) and pyrolysis atomic fluorescence (GC-pyro-AFS) detection. Aqueous ethylation with NaBEt(4) was required in all cases. All systems were validated with respect to precision, with repeatability and reproducibility <5% RSD, confirmed by the Snedecor F-test. All methods proved to be robust according to a Plackett-Burnham design for 7 factors and 15 experiments, and calculations were carried out using the procedures described by Youden and Steiner. In order to evaluate accuracy, certified reference materials (DORM-2 and DOLT-3) were analyzed after closed-vessel microwave extraction with tetramethylammonium hydroxide (TMAH). No statistically significant differences were found to the certified values (p=0.05). The suitability for water samples analysis with different organic matter and chloride contents was evaluated by recovery experiments in synthetic spiked waters. Absolute detection and quantification limits were in the range of 2-6 pg for GC-pyro-AFS, 1-4 pg for GC-MS, with 0.05-0.21 pg for GC-ICP-MS showing the best limits of detection for the three systems employed. However, all systems are sufficiently sensitive for mercury speciation in environmental samples, with GC-MS and GC-ICP-MS offering isotope analysis capabilities for the use of species-specific isotope dilution analysis, and GC-pyro-AFS being the most cost effective alternative.     

Determination of vanadium content in soils by slurry sampling electrothermal atomic absorption spectrometry using KO300G as the stabilizing agent

A direct and sensitive method for the determination of vanadium concentrations in soil is developed using ultrasonic slurry sampling electrothermal atomic absorption spectrometry (USSSETAAS). The surfactant, KO300G, is used as the stabilizing agent. The precision and accuracy of the method are investigated. The detection limits are 0.6 and 0.7 μg 1⁻¹ for SRM Montana Soil 2711 and SRM Soil — S, respectively. The method is applied to determine the vanadium content in 10 soil samples from the Wielkopolska region.     

电感耦合等离子体质谱(ICP-MS)法测定钒银矿中硒

提出了电感耦合等离子体质谱(ICP-MS)法测定钒银矿中硒的含量。样品经逆王水加高氯酸溶解,并采用内标法消除了可能存在的质谱干扰。实验结果表明,方法检出限为0.066ng/mL,加标回收率为94%~104%,测定值的相对标准偏差(n=7)均小于5.0%。方法简单、快速、准确,适用于钒银矿中硒含量的测定。     

二苯硫脲-醋酸丁酯萃取-石墨炉原子吸收法测定地球化学样品中痕量银

对石墨炉原子吸收光谱法测定地球化学样品中痕量银进行了研究。样品经盐酸、硝酸、硫酸、高氯酸溶解,在盐酸(1.2mol/L)介质中用醋酸丁酯萃取银与二苯硫脲螯合物,用石墨炉原子吸收光谱法测定地球化学样品中痕量银,方法检出限为0.011ng/mL,相对标准偏差(RSD,n=11)为6.0%~12.2%,加标回收率为96.00%~105.00%。能满足地球化学样品中银含量为0.02~5μg/g范围内银测定的准确度和精密度的要求。     

The validation of a simple LC/MS/MS method for determining the level of mevalonic acid in human plasma

A simple plasma extraction method coupled with liquid chromatography–tandem mass spectrometry (LC/MS/MS) detection was developed and validated for the analysis of endogenous mevalonic acid (MVA), a biomarker indicative of the rate of cholesterol biosynthesis, in human plasma samples. The analyte was extracted from the plasma matrix using a straightforward liquid–liquid sample preparation procedure. The extract supernatants were evaporated, reconstituted in aqueous solvent and injected into the LC/MS/MS system without further processing. The chromatographic separation was achieved on a reverse‐phase high‐performance liquid chromatography column. The accuracy and precision of the method was determined over the concentration range 0.25–25 ng/mL MVA from human plasma extracts in three validation batch runs. Inter‐assay precision (%CV) and accuracy (%RE) of the quality control samples were ≤7.00% (at lower limit quality control) and ≤6.10%, respectively. The sensitivity and throughput of this assay was significantly improved relative to previously published methods, resulting in smaller sample requirements and shorter analysis time. Assay results from a clinical study following the oral administration of an exploratory statin demonstrate that this procedure could potentially be used in the investigation of therapies associated with hypercholesterolemia. Copyright © 2010 John Wiley & Sons, Ltd.     

The determination of lead, nickel and vanadium in Saudi Arabian crude oil by sequential injection analysis/inductively-coupled plasma mass spectrometry

The coupling of sequential injection with inductively-coupled plasma mass spectrometry as an analytical tool for trace element detection is described. The technique is applied for determining the concentrations of lead, nickel and vanadium at part per billion levels in sample solutions of Saudi arabian crude oils. A microemulsion crude oil sampling procedure and a standard addition method using oil-soluble organo metallic salts of trace elements were used. A reference oil sample (NBS 1634b) was analyzed to obtain the accuracy and precision of the method. Results showed percentage recovery values of 98.2%, 95.7% and 101.4% and standard deviations of 2.9%, 1.5% and 2.0% for lead, nickel and vanadium respectively. The method is sensitive, requires only small sample volumes and is quick.     

泡塑富集-硫脲解脱电感耦合等离子体质谱法快速测定化探样品中痕量金的条件优化

针对化探样品中痕金的电感耦合等离子体质谱法快速测试方法,探讨了吸附酸度、解脱时间、吸附温度等对测试结果的影响。确立了电感耦合等离子体质谱法测定的最佳条件。方法检出限为:0.035 ng/g,准确度△lgC(n=12)为0.01～0.05,精密度RSD（n=12）为4.50～9.64。很好的解决金的快速测定问题,对地矿部门日益增多的化探任务,提高了测试速度,缩短了测试周期,值得推广。     

电感耦合等离子体发射光谱法（ICP—AES）测定红糖中的微量元素

目的红糖人药胜过白砂糖和冰糖,其机理在哪？是糖中的桔水成分,或是红糖中的矿物质成分,值得研究。方法采用微波消解法处理样品,用电感耦合等离子体发射光谱法（ICP—AES）测定红糖中的微量元素。结果14种微量元素的检测限为1．1—7．3μg·L-1,方法准确度为96．7％-109．4％,方法精密度为0．88％-9．15％。结论微波消解样品快速、准确,用ICP—AES同时测定红糖中的镁、锌、铁、铜、铬、锰、钒、锶、镍、钴、硼、铅、镉和钛等14种微量元素,检出限低,适用于红糖微量元素的常规检测。