中药材巴戟天及其水煎液微量元素的分布模式

模拟传统煎药方式,制备巴戟天水煎液。用电感耦合等离子体质谱法(ICP-MS)测定了药材及其水煎液中11种微量元素Cr、Mn、Co、Ni、Cu、Zn、As、Se、Cd、Sn、Pb含量,用火焰原子吸收光谱法(FAAS)测定了微量元素Fe含量。根据微量元素含量,得到了药材及水煎液微量元素的分布模式。结果表明,巴戟天药材样品富含人体必需元素Fe、Mn、Zn,含量分别是1086.3、393.8、15.1μg.g-1;巴戟天药材与水煎液微量元素的分布模式图清晰地显示了其微量元素的分布特征,且药材与水煎液微量元素的分布模式以及不同煎制时间下水煎液微量元素的分布模式均存在明显差异,进而表明这种微量元素分布模式对中药微量元素的研究和临床应用具有参考价值。     

钟乳石及其炮制品中Ca^2＋离子和微量元素含量的测定

对矿物中药钟乳石及其炮制品水煎液中Ｃａ＾２＋离子和微量元素的含量进行了测定，比较了生品、煅品水煎液中元素含量的变化，为研究钟乳石的化学成分与功能主治的关系提供了参考。     

中药化州橘红乙酸乙酯提取物中微量元素的分布及含量

以乙酸乙酯为溶剂萃取分离了中药化州橘红水煎液的有机成分；测定了提取物中元素的分布及含量，分析了不同微量元素在提取物中富集程度的差别。并由此说明了中药微量元素与中药所含的有机成分是有密切关系的。     

应用体外仿生模型分析海藻水煎液中微量金属的形态和生物可给性

将体外"半仿生消化"和"全仿生消化"法分别应用于海藻分析前处理,即模拟人体消化环境,加入消化液所含有机物和无机物,模拟海藻(海带和紫菜)水煎液在胃肠中的吸收和转运机制.鉴于消化管和血管间的生物膜是类脂质膜,以单层脂质体为细胞生物膜模型考察海藻水煎液中微量金属在单层脂质体-水体系中的分配行为.以单层脂质体结合态、水溶态界定水煎液中微量金属的形态; 以单层脂质体结合态含量评价微量金属的生物可给性; 比较单层脂质体结合态金属在胃肠中浓度,确定微量金属的主要吸收部位.消化酶对海藻中微量元素的形态和生物可给性影响明显.水煎液全仿生消化后,海带和紫菜中的Fe均主要在胃被吸收,海带中的Mn和Zn主要在肠被吸收;紫菜中的Mn和Zn在胃与肠均有吸收.     

悬浮液进样-石墨炉原子吸收光谱法测定中药中铜和铅的溶出率

正中药中通常含有一些微量元素~([1]),这些微量元素会在煎药过程中溶入药水中被人体摄入,只考察中药中的微量元素含量并不全面,必须对中药中各元素的含量和其在水煎液中的溶出量~([2])同时考查才有意义。文献[3-6]报道了对中药进行湿法消解后采用火焰原子吸收光谱法对其中金属元素进行测定,文献[2,7]报道了对中药进行湿法消解后采用石墨炉原子吸收光谱法对其中金属元素进行测定,未见通过悬浮液进样采用石墨炉原子吸收光谱法测定     

火焰原子吸收光谱法分析香青兰中微量元素的溶出特性及化学形态

结合香青兰的药用功效,对其铜、锌、锰、铁、镁、镍6种微量元素的含量和形态进行了分析.分别用0.45 μm滤膜、D101型大孔吸附树脂,将香青兰水煎液中铜、锌、锰、铁、镁、镍分为悬浮态和可溶态、有机态和无机态;并采取正辛醇-水分配体系模拟水煎液中铜、锌、锰、铁、镁、镍在人体胃肠中的分配情况,建立了上述6种元素的4种形态分离分析方法,用火焰原子吸收光谱法测定6种微量元素的含量、分布及其在不同溶剂中的溶出特性和化学形态.结果表明,方法的回收率在92%～106%范围内,相对标准偏差均在3.8%以下,铜、锌、锰、铁、镁、镍是各以某种形态为主的多种形态共存的混杂体系.     

红参的微量元素含量及溶出率研究

采用电感耦合等离子体发射光谱法(ICP-AES)测定了红参中15种微量元素的含量及溶出率。结果显示在红参及其水煎液中Ca，Mg，Fe，Mn，Zn，Sr，Al元素的含量较高。Cr，Al，Mg，Cd，Ni，Fe元素的溶出率较高。     

火焰原子吸收光谱法分析中药中锌的形态

采取正辛醇水分配体系模拟中药水煎液中锌在人体胃肠中的分配情况，用原子吸收光谱法测定了十二味中药药材及其水剪液中锌的含量，水煎液中水溶态锌、醇溶态锌的含量。实验结果表明，中药中锌的水煮溶出率较氏，中药中锌的形态与中药成分，配伍情况及作用靶位（胃肠）的酸度有关，酸度及配伍对中药中锌的溶出率及水煎液中锌的形态影响较大。     

不同产地磁石炮制前后元素的溶出量分析

利用吸收光度法测定三种不同产地磁石的生品和炮制品的水煎液中铁的含量,用电感耦合等离子体发射光谱法测定其余十四种元素的含量。结果表明,三种磁石中铁及微量元素的溶出量有明显差别;经煅淬后主成分铁及大部分微量元素的溶出量都有明显增加,而砷、铅的溶出量显著降低。磁 石中各种元素的溶出量与其产地和炮制有关。     

火焰原子吸收光谱法分析中药中锰的形态

1　引　　言中药中锰具抗癌、益精生血、益肝明目及提高机体抵抗力等作用。正辛醇在结构上与人体内的碳水化合物和脂肪类似 ,药理学中药物鉴定用Ｋｏｗ参数 (Ｋｏｗ =Ｃｏ Ｃｗ ,Ｃｏ 和Ｃｗ 分别为该化合物在正辛醇相和水相中的平衡浓度 )评价药物亲脂性及生物活性。正辛醇醇溶态微量元素具较强的亲脂性和生物活性 ,如作为中药有效成分 ,醇溶态含量应与中药药性、药效密切相关。本实验按中药常用煎煮方式制水煮液 ,用正辛醇 水分配体系模拟水煎液中锰在人体胃肠中的分配情况。火焰原子吸收法 (ＦＡＡＳ)测药材、水煎液中锰含量及水溶态锰、…     

分离富集技术在形态分析中应用进展

对十年来分离富集技术在形态分析中应用进展进行了评述,引用1991～2001年文献67篇。     

Investigation of DGT as a metal speciation technique for municipal wastes and aqueous mine effluents

This paper reports the results of an investigation on the performance of the Diffusive Gradient in Thin Films (DGT) Technique in speciation of metals in aqueous samples of municipal wastes and mine effluents. The DGT was assessed regarding its suitability for in situ determination of metal speciation in municipal wastes and aqueous mine effluents. As the thickness of the diffusive gel layer of the DGT was increased to 0.40, 0.80, and 1.60 mm, a decrease in the amount of accumulated metal mass was observed for most of the metals studied in all the effluent samples. However, the results were different from one field-study site to another. Effect of kinetics also was observed in the amount of accumulated metal mass by the DGT. The computer speciation code, Windermere Humic Aqueous Model (WHAM VI), was used to predict the metal speciation of Cd, Cu, Ni, Pb, Co, and Zn, and WHAM predictions were compared with those of the experimentally determined metal speciation by the DGT technique (free and labile metal ions). This comparison showed good similarities between the theoretically predicted WHAM VI values and the experimentally measured values by DGT. The DGT technique was found to be simple and useful for investigating chemical speciation of trace metals in aqueous samples of municipal wastes and aqueous mine effluents.     

HPLC-ICP-MS在食品中硒和砷形态分析及其生物有效性研究中的应用

食品中含有与人体健康密切相关的多种微量元素,微量元素的毒性和生物有效性取决于它们的化学形态。食品中的微量元素形态分析及其生物有效性研究对食品安全控制与营养评价具有至关重要的意义。本文扼要介绍了高效液相色谱与电感耦合等离子质谱（HPLC-ICP-MS）联用情况,该技术以不同的色谱分离柱完成各种分析物的分离,具有高灵敏度、高选择性、线性范围宽、检测限低、多元素同时检测等特点,在微量元素形态分析中占有重要的地位。综述了HPLC-ICP-MS在食品微量元素形态分析及其生物有效性研究中的应用,重点介绍了富硒酵母、蒜类植物、富硒营养保健品等食品中硒形态和海产品、农产品等食品中砷形态的研究,以及其它多种微量元素的形态分析和这些微量元素在生物体内的代谢。     

Effect of sample preparation on the operational speciation of cadmium and lead in a freshwater sediment

The three-stage sequential extraction procedure recommended by BCR has been applied in the operational speciation of cadmium and lead in a relatively unpolluted freshwater sediment, following various types of sample pre-treatment. Changes in speciation occurred when the sediment was air-dried, oven-dried or frozen. Cadmium speciation was particularly perturbed by freezing, whilst lead was more affected by oven-drying. Metals were determined by electrothermal atomic absorption spectrometry, using direct calibration with reagent-matched standard solutions.     

Effect of dehydration on sulfate coordination and speciation at the Fe-(hydr)oxide-water interface: a molecular orbital/density functional theory and Fourier transform infrared spectroscopic investigation

The effect of dehydration on the coordination and speciation of sulfate at the Fe-(hydr)oxide-H2O interface was investigated using molecular orbital/density functional theory (MO/DFT) and Fourier transform infrared (FTIR) spectroscopy. IR frequency calculations were performed at the UB3LYP/6-31+G(d) level of theory for potential sulfate (bidentate bridging, monodentate, and H-bonded) and bisulfate (bidentate bridging and monodentate) surface complexes. MO/DFT calculated IR frequencies were compared to available IR literature results and attenuated total reflectance (ATR) FTIR spectra collected in our laboratory of sulfate adsorbed at the hematite-H2O interface. IR frequency calculations performed using the larger 6-311+G(d,p) basis set resulted in minor frequency shifts that did not dramatically alter the agreement with experiment. This investigation proposes that sulfate undergoes a speciation change as a function of surface dehydration. A generalized model for the speciation change is proposed as follows. (1) At the Fe-(hydr)oxide-H2O interface, sulfate adsorbs as a bidentate bridging or monodentate surface complex under most experimental conditions. (2) Upon surface dehydration, sulfate changes speciation to form bidentate bridging and/or monodentate bisulfate. However, surface dehydration does not yield 100% speciation change but leads to a mixture of sulfate and bisulfate. (3) The speciation change is reversible as a function of rehydration. The reversibility of the sulfate-bisulfate speciation change is chiefly determined by the local hydration environment of the O-H bond in bisulfate. Under dehydrated conditions, the O-H bond length is approximately 0.98 A. The bond length substantially increases (bond strength decreases) to approximately 1.03 A when the initial H-bond network is re-established through hydration, likely leading to deprotonation upon full mineral surface hydration.     

Metal ion speciation and capillary electrophoresis: application in the new millennium

Metal ions are essential for human beings at low concentrations but they are toxic or even carcinogenic at high concentrations. Many metallic ions are found in the environment in different species which are differentiated not only by their physicochemical forms but also by their diverse toxicities with respect to living organisms (speciation). CE has been used for metal ion speciation. The present review article describes the recent trends in metal ion speciation by CE. This article deals with the speciation of metal ions, optimization of the speciation (by independent and dependent variables), hyphenation of CE, validation of the methods, mechanisms of speciation, CE versus chromatography and conclusions.     

Effect of sample preparation on the operational speciation of cadmium and lead in a freshwater sediment

The three-stage sequential extraction procedure recommended by BCR has been applied in the operational speciation of cadmium and lead in a relatively unpolluted freshwater sediment, following various types of sample pre-treatment. Changes in speciation occurred when the sediment was air-dried, oven-dried or frozen. Cadmium speciation was particularly perturbed by freezing, whilst lead was more affected by oven-drying. Metals were determined by electrothermal atomic absorption spectrometry, using direct calibration with reagent-matched standard solutions. Received: 18 March 1998 / Revised: 22 June 1998 / Accepted: 26 June 1998     

Factors affecting arsenic speciation in environmental samples: sample drying and storage

Arsenic is a ubiquitous element. Its toxicity, mobility, and bioaccumulation depend usually on its chemical form, and therefore, arsenic speciation is indispensable for the assessment of environmental risk and human hazard. Little is known about the effect of sample preparation procedures, such as drying and storage, on the resulting arsenic speciation. In this study, we investigated the influence of different drying methods and storage conditions on the arsenic speciation in mineral soils, organic soils, and plants. Drying soils and plants using different methods may change the concentrations of the total methanol–water (20%,?v/v) extractable arsenic, the proportion of organic arsenic and the ratio of arsenite-to-arsenate. Loss of methanol–water extractable arsenic compounds (up to 63%) was observed particularly in the samples rich in water. Following drying, the speciation of organic arsenic changed less than that of inorganic arsenic. Drying showed little influence on the total arsenic determination. None of the storage methods tested could preserve the arsenic speciation in organic soils and plants, although arsenic speciation after one-month storage varied less in freeze-dried samples than wet samples. Storage of the samples at low temperatures (2 or??20°C) had the largest impact on the samples rich in organic matters, leading to less arsenic being extractable by methanol–water. Both drying and storage of the soil and plant samples changed apparently the arsenic speciation. Therefore, we recommend conducting the arsenic speciation possibly with fresh and wet samples, so that the results of arsenic speciation may be more approaching the original states.     

土壤中镉及镉的赋存形态研究进展

综述了土壤中镉及镉的赋存形态研究进展,包括:土壤环境中镉及其污染来源,土壤中镉的赋存形态,镉赋存状态同镉生物活性的关系,土壤性状对镉赋存形态的影响,土壤中镉的测定方法等。     

铝壶煮沸的饮用水中铝的形态分析

用过滤、离子交换和光解氧化分离自来水和经铝壶煮沸的饮用水中铝的形态,以石墨炉原子吸收光谱法测定铝的浓度,采用化学平衡模式计算铝的形态分布。实验结果表明：经铝壶煮沸１ｍｉｎ的饮用水中颗凿态铝量比自来水降低了３．３倍,可交换态、不可交换有机态、不可交换无机态铝量分别２增加了１．４、０．５和１．２８倍,可交换态和不可交换无机态是铝的主要存在形态。随着煮沸时间的增加,可交换态、不可交换有机态、不可交换无机