中成药质量稳定性的原子吸收光谱鉴别分析

对全国各地用原子吸收光谱仪测定10批次大活络丸中12种无机元素及建立的指纹图谱,尝试用成分数据分析法、向量相似法和模糊聚类法建立全国无机元素的指纹图谱和中药质量控制标准方法,获得较满意的结果。研究表明,建立无机元素指纹图谱控制中成药中无机元素的质量,具有很好的实用性和可操作性,用于全国各地不同厂家生产的大活络丸无机元素的质量控制是切实可行的。     

电感耦合等离子体原子发射光谱分析中易电离元素的基体干扰及其抑制的研究

选取铝、铜、镁、钙、铁、锰和锌等7种元素的9条谱线,研究电感耦合等离子体原子发射光谱法对其测定时易电离元素钾、钠的基体干扰。结果表明:易电离元素对待测元素具有较明显的干扰作用,而增大射频发射功率及降低雾化器压力可有效地抑制易电离元素对待测元素的干扰。     

电感耦合等离子体发射光谱法测定地质样品中K、Ca等常量元素的前处理方法对比

通过以标准物质玄武岩为试验对象,分别使用酸溶法和碱熔法进行样品前处理,采用电感耦合等离子体发射光谱法（ICP-OES）测定,二者均取得了良好的结果.其中,酸溶法对样品的消解更为彻底,元素的提取更为完全,与标准物质元素推荐值之间的误差更小.但碱熔法流程更为简单,所需时间短,且不影响样品Si元素的测定.总体来说,碱熔法适合用于常规地质样品常量元素的前处理,酸溶法适合于较难溶解的地质样品常量和痕量元素的测定.二者均对试验细节有较高的要求.实际应用中,需不断改进试验方法,严谨试验细节,以获得更简便的方法和更准确的结果.     

缝管原子捕集法中的原子化机理

本文用Ｘ射线衍射分析法研究了１１个元素在开缝石英管中原子捕集与释放机理。Ａｇ和Ｂｉ以金属形式被捕集，而Ｃｄ、Ｃｕ、Ｉｎ、Ｎｉ、Ｓｂ、Ｚｎ、Ｐｂ、Ｃｏ、Ｇａ则以氧化物或硅酸盐形式捕集。这些元素在放时直接从熔融物蒸发原子化。５％乙醇或丙酮能提高大多数元素的灵敏度。大多数元素在Ａｌ２３涂层管上的灵敏度较高，在Ｌａ２Ｏ３涂层管上的检出限较低，精密度较高。     

元素成像技术在核法证中的应用研究进展

核法证学是打击非法贩卖核材料和放射性物质的重要工具,可用于对截获的材料进行分析溯源。过去的研究主要集中于元素和同位素特征的总体分析表征。近年来,随着微分析技术的发展,微米尺度和纳米尺度元素和同位素空间分布特征、微观形态学特征研究正成为核法证学研究的热点。本文基于近年来国内外核法证学的研究成果,详细介绍了元素成像技术在核法证学材料分析领域元素和同位素成像、微观形态学方面的应用研究进展。     

氟化络合-ICP-MS法测定稀土金属中的难熔金属杂质元素Ta、Mo、W、Ti、Nb

针对稀土金属中难熔金属杂质元素Ta、Mo、W、Ti、Nb在HCl或HNO3中不易溶解的性质,本文在前人工作基础上,采用HF络合-ICP-MS结合的方法,有效地将上述元素溶解在溶液中,并利用ICP-MS高灵敏度和多元素同时测定的优势,成功建立了稀土金属中难熔金属杂质元素Ta、Mo、W、Ti、Nb的测定方法。其操作过程较传统化学方法简便,灵敏度也更高。本文分析了氢氟酸的络合过程,试验了稀土氟化物沉淀对被测元素的吸附作用和内标法的校正作用。方法检出限在0.3～1.5ng／mL,测定下限0.0005％～0.0010％,回收率在89.2％～118.9％,相对标准偏差为4.6％～9.7％。     

木棉花中微量元素的测定

采用原子吸收法测定木棉花中铜、锌、钾、钠、钙、镁、锶和锂元素含量,对进一步研究木棉花的无机元素和综合开发利用提供了参考的数据。     

再谈f区元素定义的争论*

f区元素作为周期表中重要的一个区块,掌握其性质对于元素周期表以及元素性质的学习至关重要。通过回顾f区元素定义的发展历史,进一步阐明了f区元素结构与性质的相关性。     

ICP-AES法测定出口工业硅中11种杂质元素

利用ICP-AES分析技术,对试样溶解方法,元素分析谱线,共存元素干扰,仪器分析参数,无机酸介质影响等因素进行了研究,确定了最佳工作条件,建立了可同时测定出口金属硅中11种杂质元素的简单、快速和适用的分析方法,结果表明,该方法线性范围宽,检出限低,准确性高,操作步骤简单,11个元素测定回收率在85％～105％之间,相对标准偏差在1．9％～8．1％之间。     

基于ICP-MS分析的苜蓿矿质元素含量特征与评价

为了探明进口和国产苜蓿总体矿质差异,以国产和进口苜蓿为对象,采用石墨消解-电感耦合等离子体质谱(ICP-MS)法分析干草中磷、钾和锌等17种矿质元素的含量特征,并对矿质元素含量进行了相关性、主成分分析和评价。结果表明,苜蓿干草中矿质元素种类丰富而含量变异较大,平均含量最高的是K元素,其次是Ca>Mg>Na>P,Al元素含量显著高于其他11种微量元素。Cu、K、Mg、Al、K、Ca两两元素间存在极显著正相关(p<0.01);Ca、Cu、Mg、K、Zn、Co和Na是苜蓿干草的主要特征矿质元素,累积方差贡献率达74.90%。进口苜蓿中K、Ca、Mg、Cu含量显著高于国产苜蓿,而国产苜蓿中Na和Co含量显著高于进口苜蓿。针对国产苜蓿营养缺乏,应在选种和肥料管理中重视增施钾肥和其他微量元素,合理利用苜蓿草产品。     

Selenium speciation in animal tissues after enzymatic digestion by high-performance liquid chromatography coupled to inductively coupled plasma mass spectrometry

A procedure is described for the enzymatic digestion of tuna and mussel samples that allows the determination of selenium species by high-performance liquid chromatography in conjunction with inductively coupled plasma mass spectrometry. The species were extracted by two-step enzymatic hydrolysis with a non-specific protease (subtilisin). The selenium species were separated on a Spherisorb 5 ODS/AMINO column using two different chromatographic conditions, namely phosphate buffers at pH 2.8 and pH 6.0 as mobile phases. The method determines organic (trimethylselenonium, selenocystine, selenomethionine and selenoethionine) and inorganic selenium species (selenite and selenate), but only organic selenium species were found in the samples. The sum of identified selenium species in the sample was about 30% of the total selenium present in the enzymatic extract despite the fact that recoveries of total hydrolysed selenium were 93-102%. Trimethylselenonium ion and selenomethionine were found in both tuna and mussel samples and an unknown selenium species was also found in tuna samples.     

Mercury in fish products: what’s the best for consumers between bluefin tuna and yellowfin tuna?

A total of 205 bluefin and yellowfin tuna samples were examined for mercury detection in order to verify possible differences and have a detailed risk assessment of the two tuna species. The results showed significant higher mercury concentration in muscle tissue of bluefin tuna respect yellowfin tuna (p < 0.001) with mean concentration of 0.84 mg/kg and maximum value of 1.94 mg/kg. These differences can be due the different biological and ecological aspects of the two tuna species and to different oceanographic aspects between Atlantic Ocean and Mediterranean sea. The results obtained in this study suggest an advisable containment of the sources of pollution and further studies on the closed-loop farming of bluefin tuna, in order to ensure the product safety.     

Fast method for routine simultaneous analysis of methylmercury and butyltins in seafood

A simple, fast, and accurate method for the simultaneous determination of methylmercury (MeHg(+)), monobutyltin (MBT), dibutyltin (DBT) and tributyltin (TBT) in seafood is proposed. The method makes use of relatively cheap instrumentation and allows simultaneous analysis of those four species in a routine basis. The sample is treated with methanolic potassium hydroxide in an ultrasound bath, derivatised with sodium tetraethylborate (NaBEt(4)), preconcentrated into n-hexane and analysed by gas chromatography with atomic emission detection (GC-MIP/AES). The soft extraction conditions provided by ultrasound energy prevent chemical decomposition of the analytes and allow fast and efficient recovery of the species considered. Both the extraction and the derivatisation/preconcentration steps were optimised. Detection limits of 34, 3, 6 and 8 ng g(-1) (dry mass) were obtained for MeHg(+), MBT, DBT and TBT, respectively, using the best experimental conditions found. The uncertainty of the analysis ranged from 11% (MeHg(+)) to 15% (MBT). The accuracy of the method was checked by the analysis of several certified reference materials, e.g., BCR 477 (mussel tissue, MBT, DBT and TBT), DOLT-2 (dogfish liver, MeHg(+)), BCR 463 (tuna fish, MeHg(+)) and NIST 2976 (mussel tissue, MeHg(+)) with satisfactory results. Several oyster samples collected in the estuary of the Oka River (Urdaibai, Unesco Reserve of the Biosphere, Basque Country) during four sampling campaigns in 2003-2004 were processed following the proposed procedure. Concentrations ranging from 65 to 149 ng g(-1) (MeHg(+)), 相似文献   

Optimization of a centrifugation and ultrasound-assisted procedure for the determination of trace and major elements in marine invertebrates by ICP OES

A three factor Doehlert design was applied to optimize the extraction of elements in marine invertebrate samples (oyster, mussel and clam) using centrifugation with diluted acids. The factors were: concentration of acid mixture (HCl + HNO₃ + H₃CCOOH; 1–3 mol L^{− 1}), centrifugation time (10–40 min), and rotation velocity (6000–10,000 rpm). In order to evaluate the ultrasound effect on the extraction of trace metals, a portion of the certified oyster tissue sample (NIST 1556b; 0.250 g) was sonicated for 15 min and then the solution was centrifuged at the optimized conditions. The optimized procedure was then applied to nine marine invertebrate samples (oysters, clams and mussels) collected at Todos os Santos Bay, Bahia, Brazil. The optimized condition of the developed method was: 20 min of centrifugation at 9000 rpm using the acid mixture 1.0 mol L^{− 1}. The effect of sonication prior centrifugation was very variable, but it promoted a significant increase in the extraction (12 to 44%) of some trace elements. Moreover, the combination of the centrifugation with sonication offered other advantages, such as improvement of the precision and accuracy, both demonstrated using the oyster tissue reference sample. The results of major and trace elements in marine invertebrate samples showed that elements such us Cd and Cu in oyster samples and Zn in mussel and clam samples were above recommendations, suggesting that its consumption may impose health risks.     

Determination of paralytic shellfish toxins in shellfish by receptor binding assay: collaborative study

A collaborative study was conducted on a microplate format receptor binding assay (RBA) for paralytic e shellfish toxins (PST). The assay quantifies the composite PST toxicity in shellfish samples based on the ability of sample extracts to compete with (3)H saxitoxin (STX) diHCl for binding to voltage-gated sodium channels in a rat brain membrane preparation. Quantification of binding can be carried out using either a microplate or traditional scintillation counter; both end points were included in this study. Nine laboratories from six countries completed the study. One laboratory analyzed the samples using the precolumn oxidation HPLC method (AOAC Method 2005.06) to determine the STX congener composition. Three laboratories performed the mouse bioassay (AOAC Method 959.08). The study focused on the ability of the assay to measure the PST toxicity of samples below, near, or slightly above the regulatory limit of 800 (microg STX diHCl equiv./kg). A total of 21 shellfish homogenates were extracted in 0.1 M HCl, and the extracts were analyzed by RBA in three assays on separate days. Samples included naturally contaminated shellfish samples of different species collected from several geographic regions, which contained varying STX congener profiles due to their exposure to different PST-producing dinoflagellate species or differences in toxin metabolism: blue mussel (Mytilus edulis) from the U.S. east and west coasts, California mussel (Mytilus californianus) from the U.S. west coast, chorito mussel (Mytilus chiliensis) from Chile, green mussel (Perna canaliculus) from New Zealand, Atlantic surf clam (Spisula solidissima) from the U.S. east coast, butter clam (Saxidomus gigantea) from the west coast of the United States, almeja clam (Venus antiqua) from Chile, and Atlantic sea scallop (Plactopecten magellanicus) from the U.S. east coast. All samples were provided as whole animal homogenates, except Atlantic sea scallop and green mussel, from which only the hepatopancreas was homogenized. Among the naturally contaminated samples, five were blind duplicates used for calculation of RSDr. The interlaboratory RSDR of the assay for 21 samples tested in nine laboratories was 33.1%, yielding a HorRat value of 2.0. Removal of results for one laboratory that reported systematically low values resulted in an average RSDR of 28.7% and average HorRat value of 1.8. Intralaboratory RSDr based on five blind duplicate samples tested in separate assays, was 25.1%. RSDr obtained by individual laboratories ranged from 11.8 to 34.9%. Laboratories that are routine users of the assay performed better than nonroutine users, with an average RSDr of 17.1%. Recovery of STX from spiked shellfish homogenates was 88.1-93.3%. Correlation with the mouse bioassay yielded a slope of 1.64 and correlation coefficient (r(2)) of 0.84, while correlation with the precolumn oxidation HPLC method yielded a slope of 1.20 and an r(2) of 0.92. When samples were sorted according to increasing toxin concentration (microg STX diHCl equiv./kg) as assessed by the mouse bioassay, the RBA returned no false negatives relative to the 800 microg STX diHCl equiv./kg regulatory limit for shellfish. Currently, no validated methods other than the mouse bioassay directly measure a composite toxic potency for PST in shellfish. The results of this interlaboratory study demonstrate that the RBA is suitable for the routine determination of PST in shellfish in appropriately equipped laboratories.     

利用GC/MS测定海洋中贻贝、牡蛎体内的多环芳烃

应用毛细管柱气相色谱／质谱（GC／MS）联用技术对贻贝,牡蛎体内的几种多环芳烃含量进行了分析研究,贻贝,牡蛎样品经超声提取,层析分离后,由GC／MS测定,采用选择性离子检测模式,定性,定量检出了几种多环芳烃。     

Determination of rare earth elements in environmental matrices by sector-field inductively coupled plasma mass spectrometry

In the framework of an international certification campaign, sector-field inductively coupled plasma mass spectrometry (sector-field ICP-MS) was used for the accurate determination of the rare earth elements in five candidate reference materials: aquatic plant, calcareous soil, mussel tissue, river sediment, and tuna muscle. All samples were taken into solution by use of microwave-assisted or mixed microwave-assisted / open beaker acid digestion. Subsequently, the samples were appropriately diluted and subjected to ICP-MS analysis. Except for Sc, all the elements involved were determined at low mass resolution (R = 300). For Sc, application of a higher resolution setting (R = 3,000) was required to separate the analyte signal from those of several molecular ions which gave rise to spectral overlap at low mass resolution. Some of the heavier REE can also suffer from spectral overlap attributed to the occurrence of oxide ions (MO+) of the lighter REE and Ba. This spectral overlap could be successfully overcome by mathematical correction. Matrix effects were overcome by use of two carefully selected internal standards, such that external calibration could be used. On each occasion, a geological reference material was analyzed as a quality-control sample and the reliability of all results obtained was additionally checked by means of chondrite normalization. For tuna muscle the content of all REE was below the limit of detection. For calcareous soil and river sediment, low to sub microg g(-1) values were observed, whereas the REE content of aquatic plant and mussel tissue was considerably lower (low to sub ng g(-1)). Overall, the results obtained were in excellent agreement with the average values, calculated on the basis of all "accepted" values, obtained in different laboratories using different techniques.     

Focused ultrasound and molecularly imprinted polymers: a new approach to organotin analysis in environmental samples

There is a high interest in speciation of organotin compounds (OTCs) in biota and marine sediment samples, due to their influence in the transmission of the contamination in the trophic chain. Sample treatment is still the most "compromising" step of speciation analysis. Extraction methods are in general time-consuming due to long extraction times and several analytical steps involved. In addition, in most cases there are problems of low recovery, especially for MBT. These drawbacks, added to the high matrix effects generally present in biota samples, make the sample treatment for organotin analysis a serious challenge for environmental issues. Here we present a novel, fast and efficient two steps method for organotin speciation in mussel and oyster tissue as well as in marine sediments. The first step based on the use of ultrasonic probe extraction for species leaching allowed us to quantitatively extract these compounds in a few minutes. Matrix interferences drastically decreased by applying a clean-up step based on the use of an imprinted polymer especially designed for tributyltin (TBT). This procedure increased accuracy and precision of the GC-FPD analysis and improving the limit of detection, Besides, this new method prevents the use of standard addition calibration method, which is mandatory without the clean-up step. The optimization and validation has been performed by using three reference materials: mussel tissue CRM-477, oyster candidate T-38 and sediment PACS-2.     

五种中药中微量元素及重金属元素的含量分析

用微波消解-原子吸收分光光度法对巴戟天、大黄、陈皮、板蓝根、茯苓等5种中药材中的7种金属微量元素进行了含量分析。结果表明,该法的线性良好,重现性在3.3%~11%之间,精密度在2.6%以内,回收率满足定量分析要求;5种药材中铅均未超标,茯苓中镉超出国家标准;5种药材里的铜含量均有超标,其中,巴戟天超标最严重;铁在5种药材中的含量最高,其中以巴戟天含量最为丰富,达到了746.750 mg/kg,其次是锌和锰,铬的含量最少。结论:对5种药材中铜均出现超标,虽然在边缘位置,但应该予以重视;巴戟天中丰富的铁元素,可能在防止癌变发生和发展中起到一定功效。     

Domoic acid--a new toxin in the Croatian Adriatic shellfish toxin profile

This is the first study that presents concentrations of domoic acid detected in the whole shellfish tissue from breeding and harvesting areas along the Croatian coast of the Adriatic Sea during the period 2006 to 2008. Shellfish sample analyses after SAX cleaning procedures, using a UV-DAD-HPLC system, showed the presence of domoic acid in four species. The most prevalent of those species were the blue mussel (Mytilus galloprovincialis), followed by European flat oyster (Ostrea edulis), Mediterranean scallop (Pecten jacobaeus) and proteus scallop (Flexopecten proteus). Domoic acid, a potentially lethal phycotoxin that causes amnesic shellfish poisoning (ASP), was detected for the first time in January 2006 with the highest value of 6.5486 μg g?1 in whole shellfish tissue. Pseudo-nitzschia spp. bloom events preceded these high domoic acid concentrations. According to this study, retention of domoic acid in the blue mussel M. galloprovincialis is more than 42 days. This investigation indicates the first presence of domoic acid in Croatian shellfish, but in concentrations under the regulatory limit (20 μg g?1), therefore shellfish consumption was not found to endanger human health.