高效液相色谱光度法测定痕量铜、锌、铁、锰的磺化四苯基卟啉配合物

本文用磺化四苯基卟啉作柱前衍生试剂,研究了试剂与铜(Ⅱ)、锌(Ⅱ)、铁(Ⅲ)及锰(Ⅱ)的络合反应。在ODS柱上,用乙腈-水(40:60,V/V)作流动相,溴化四丁基铵作离子对试剂,在420nm波长处进行光度检测。提出了离子对反相高效液相色谱快速分离及测定痕量铜、锌、铁及锰的新方法。检测下限为(×10^-3ppm):Mn 3.6、Fe 1.8 、Zn 0.93、Cu 0.70。应用于植物样品中痕量铜、锌、铁及锰的测定,分析结果与标准参考值相符。     

ICP－直读光谱快速测定铝合金中主要成分Ti、V、Zr、Mn及次要成分Si、Fe、Mg

本文用ＩＣＰ－ＡＥＳ法顺序测定了铝合金中的主要成份如Ｔｉ、Ｖ、Ｚｒ、Ｍｎ和次要成分如Ｓｉ、Ｆｅ、Ｍｇ。采用正交设计法优化了仪器和操作参数。研究了样品产生的条件干扰。本法简单、极大地提高了分析速度。方法的相对标准偏差在１．７％～２．８％。     

T（3－BrP）PS_4卟啉用于高效液相色谱法测定微量钴、锌、铜

新显色剂５，１０，１５，２０－四（３－溴－４－磺酸苯基）卟啉，即Ｔ（３－ＢｒＰ）ＰＳ_４，与Ｃｏ（Ⅱ）、Ｚｎ（Ⅱ）、Ｃｕ（Ⅱ）离子生成螯合物，可在岛津ＣＬＣＯＤＳ柱上用离子对反相高效液相色谱法（ＨＰＬＣ）分离。流动相为２７＋７３的乙腈＋水，内含２０ｍｍｏｌ／Ｌ的乙酸＋乙酸钠缓冲液（ｐＨ６．０）和１０ｍｍｏｌ／Ｌ的四乙基碘化铵（ＴＥＡ·Ｉ）。检测波长为４２０ｎｍ。应用于茶叶、桔皮和紫米中微量钴、锌，铜离子的测定中，结果满意。     

1─（2─吡啶偶氮）─2─萘酚─6─磺酸衍生化反相高效液相色谱法测定铁、钴、镍

本文研究了水溶性试剂１－（２－吡啶偶氮）－２－萘酚－６－磺酸（ＰＡＮ－Ｓ）与铁（Ⅱ）、钴（Ⅱ）和镍（Ⅱ）之螯合物的衍生和液相色谱分离条件。在Ｎｏｖａ－ＰａｋＴＭＣ１８柱上，用含１０ｍｍｏｌ／Ｌ的ｐＨ５．０的醋酸－醋酸钠缓冲溶液的甲醇－水溶液（５０：５０，Ｖ／Ｖ）作流动相，溴化四丁基铵（ＴＢＡ·Ｂｒ）作离子对试剂，流动相流速为１．０ｍＬ／ｍｉｎ，在５５０ｎｍ波长处进行光度检测。在Ⅱｍｉｎ内用高效液相色谱分离测定了Ｆｅ（Ⅱ）、Ｃｏ（Ⅱ）和Ｎｉ（Ⅱ）与ＰＡＮ—Ｓ的螯合物，提出了离子对反相高效液相色谱快速分离测定痕量铁、钴、镍的新方法。信噪比（ＳＮＲ）为２时，检测下限分别为０．０４３、０．００７和０．０１２ｍｇ／Ｌ。     

离子色谱法快速同时测定营养药物中微量铜、锰、锌

在ＨＰＬＣ－ＣＳ５阳离子分离柱上选用５．０×１０￣（－２）ｍｏｌ／Ｌ草酸（ｐＮ为５．２４）作淋洗液分离了微量Ｃｕ￣２＋、Ｍｎ￣２＋和Ｚｎ￣２＋离子,用４－（２－吡啶偶氮基）间苯二酚作显色剂在５２０ｎｍ处连续检测,方法快速、简便、准确。本法用于施尔康片中微量Ｃｕ￣２＋、Ｍｎ￣２＋和Ｚｎ￣２＋离子的测定,结果令人满意。     

微波消解-微波等离子体矩原子发射光谱法测定乳胶管中的铁、钙、镍、镁、锌

本文研究了用HNO3-H2O2微波消解样品,微波等离子体矩原子发射光谱(MPT-AES)测定乳胶管中铁,钙,镍,镁,锌的含量方法。详细考察了测定铁、钙、镍、镁、锌的最佳实验条件,以及介质酸、共存离子的影响。本方法测定铁、镍、镁、钙、锌的检出限分别为77.80、7.55、2.70、275.87、46.23 ng/mL,方法的精密度分别为3.10%、2.19%、2.22%、1.27%、2.90%,线性范围分别为0.08~2 mg/L0、.06~2 mg/L0、.001~3 mg/L、0.005~2 mg/L、0.05~1 mg/L,加标回收率分别在97.7%~107.8%、96.0%~106.7%、98.0%~106.2%、92.3%~108.8%、98.7%~106.8%范围。     

磷、砷、硅钼杂多酸-罗丹明6G荧光猝灭法连续测定磷、砷、硅的研究

本文报道了在非离子表面活性剂PVA存在下,磷、硅、砷钼杂多酸-罗丹明6G形成离子缔合物,使罗丹明6G荧光猝灭。研究了罗丹明6G-磷、砷、硅钼杂多酸体系荧光光谱,形成条件和配合物组成。试验了共存离子的干扰。应用此方法对铜合金中磷、砷、硅进行同时测定,结果满意。     

吡啶-2,6-二羧酸体系荧光法同时测定地质和环境试样中的钐、铕、铽、镝

本文研究了吡啶-2,6-二羧酸体系荧光法同时测定钐、铕、铽、镝的最佳条件及共存离子的影响。其检测限分别为3.0、0.15、0.09和0.5mg/mL。本文采用荧光法与阳离子交换树脂分离法联用,同时测定了地质和环境试样中的杉、铕、铽、镝含量。     

5，10，15，20－四（3－溴－4－磺酸苯基）卟啉高效液相色谱法测定河水中微量钴、铜、锌

研究了新合成的显色剂５,１０,１５,２０－四（３－溴－４磺酸苯基）卟啉与Ｃｏ(Ⅱ）、Ｚｎ（Ⅱ）、Ｃｕ（Ⅱ）形成配合物离子的反应,在ＺＯＲＢＡＸＯＤＳ柱上,用含２０ｍｍｏｌ／Ｌ 乙酸－乙酸钠（ｐＨ６．０）和１０ｍｍｏｌ／Ｌ四乙基碘化铵的乙腈－水（２７：７３,Ｖ／Ｖ）流动相洗脱,在４２０ｎｍ波长下检测。Ｃｏ（Ⅱ）、Ｚｎ（Ⅱ）、Ｃｕ（Ⅱ）赘合物在９ｍｉｎ内获得完全分离,检测限分别为０．２ｎｇ,０．０５ｎｇ和０．０９ｎｇ。该方法已用于河水样中钴、锌、铜的测定。     

抑制型离子色谱快速测定I~－、SCN~－、S_2O_3~（2－）

本文用抑制型离子色谱，薄壳强碱性阴离子交换树脂为分离柱，柱温为３０±１℃，在常规淋洗液ＮａＨＣＯ＿３－Ｎａ＿２ＣＯ＿３中加入对－硝基苯酚作为有机改进剂，测定了Ｉ￣－、ＳＣＮ￣－、离子。它们有良好的线性关系，三种离子的浓度在５．０～３０．０ｍｇ／Ｌ范围内其相关系数分别为：０．９９９４、ｒ＿（ＳＣＮ）￣（－０．９９０６），检测限分别为：Ｉ￣－０．１７ｍｇ／Ｌ、ＳＣＮ￣－０．１０ｍｇ／Ｌ、Ｌ。     

Synthesis and binding studies of new bis-calix[4]arenes containing aromatic and heteroaromatic units

A series of new bis-calix[4]arenes containing different aromatic and heteroaromatic moieties have been synthesized. The complexing behavior of these bis-calix[4]arenes have been studied towards different metal ions and it has been found that these bis-calix[4]arenes bind silver ions selectively over other metal ions. The complexation has been studied by liquid-liquid extraction and by NMR and IR spectroscopy.     

BPR树脂对Au(Ⅰ)、Ag(Ⅰ)等氰合离子的离子交换与吸附研究(Ⅰ)——吸附、解吸动力学

考察了BPR树脂在碱性条件下对金的吸附性能。研究了BPR提取Au(Ⅰ)、Ag(Ⅰ)及其它金属氰合离子的单、双组分动力学传质过程。结果表明,树脂相上氰合离子的传质速率和摩尔比与其结构类型有密切的关系,对Au(Ⅰ)等氰合离子的NH₄SCN解吸动力学作了系统的考察。     

Fluorescence Enhancement of Levosulpiride Upon Coordination with Transition Metal Ions and Spectrophotometric Determination of Complex Formation

Abstract

Absorbance and fluorescence spectral pattern of levosulpiride in absence and presence of first row transition metal ions (Mn-Zn) has been studied at room temperature under physiological condition. The fluorescence spectra of the drug in presence of different concentrations of transition metal ions showed enhancement in fluorescence intensity of levosulpiride. The photophysical changes owing to the direct interaction between metal ion and the amide nitrogen of levosulpiride has been described in terms of CHEF (chelating enhancement fluorescence) effect. The absorption spectra of the drug at different pH exhibited two isosbestic points at 255 and 275 nm respectively, indicating the presence of three chemical species in solution. The ratio of the drug to metal ions is found to be 2:1 and the log K of the resulting complex was determined spectrophotometrically and potentiometrically. The apparent ionization constant of levosulpiride is found to be 8.98. The low value of stability constant suggests that complexes may dissolve and the drug can be absorbed.     

Simultaneous recovery of cadmium and lead from aqueous effluents by a semi-continuous laboratory-scale polymer enhanced ultrafiltration process

Performance of a semi-continuous polymer enhanced ultrafiltration (PEUF) process has been investigated for the simultaneous recovery of cadmium and lead from binary mixtures. This method uses poly(acrylic acid) as water-soluble polymer to bind these metals. Experiments have taken place in a laboratory-scale system. Loading ratio (mg total metal ions/g polymer) and pH values for separation of cadmium and lead have been studied by means of preliminary experiments, analyzing their influence on permeate flux, metal rejection coefficients and separation factor.The proposed process includes three different stages: total retention of metal ions, selective separation and polymer regeneration. Operating pH values for total retention of metal ions and polymer regeneration processes are 5 and 2, respectively. Selective separation has been investigated working at an intermediate pH value. In this way, if a stream containing 12.5 ppm of each metal ion (1:1 in weight) is treated in the first stage, two different streams enriched in each metal ion are obtained in the second stage. Permeate stream is enriched in cadmium with a proportion near 5:1 in weight, and retentate is enriched in lead with a similar proportion.Finally, the three stages have been modelled successfully with a mathematical model based on conservation equations and chemical reactions taking place in solution.     

Alkali cation attachment to derivatized fullerenes studied by matrix-assisted laser desorption/ionization

The complexation of alkali metal ions with amphiphilic fullerene derivatives has been investigated by matrix-assisted laser desorption/ionization (MALDI) time-of-flight (TOF) mass spectrometry. The formation of analyte ions occurs via two competing mechanisms including electron transfer from matrix-derived ions and metal ion attachment. The interplay of these processes has been examined by laser fluence dependent sample activation and by variation of the target composition. The attachment of metal ions has been established as the gentler and thus more efficient route towards the formation of intact analyte ions. Investigations into the metal ion complexation have been conducted to reveal the reactivity order of the alkali metals in these reactions and to elucidate the influence of structural differences of the analytes, as well as to unravel effects caused by the anionic counter ion of the metal. The experimental data have been derived by two complementary approaches. Competing reactants were either studied simultaneously, so that the product distribution would provide direct insight into the reactivity pattern, and/or product distributions were obtained in a large variety of separate experiments and normalized for reliable comparison. It has been found that the extent to which complexation is observed follows the charge density order of the alkali metal ions. The structural features of the fullerene-attached ligands were of profound influence on the attachment of the metal ion, inducing enhanced selectivity for the complexation with less reactive metals. The metal ion attachment is reduced with the use of smaller anionic counter ions. Rationalization of these findings is provided within the framework of the mechanisms of ion formation in MALDI.     

Adsorption of Cu(II) on porous chitosan membranes functionalized with histidine

The ability of chitosan to form complexes with bivalent metal ions has been broadly explored in the literature. The present work investigates the influence of functionalization of macroporous chitosan membranes with histidine on their ability to remove copper ions from aqueous solution in the range of pH 4–6. The maximum adsorption capacity for Cu(II) ion was 2.5 mmol metal/g pristine chitosan membranes. Under this condition, no influence of membrane porosity was observed. However, for membranes with immobilized histidine, the porosity was shown to be a factor that affects the maximum adsorption capacity, with values ranging from 2.0 to 3.0 mmol metal/g chitosan. These results indicate that the immobilization of histidine on porous chitosan membranes presents synergy with porosity in the ability to complex Cu(II) ions. This synergy may be negative or positive, depending on the initial membrane porosity.     

不同价态金属离子对DNA构象的影响

用紫外分光光度法研究了不同价态金属离子对DNA大分子溶液构象的影响。研究结果显示: 金属离子与DNA的作用使DNA溶液的紫外吸收值下降, 即呈现减色效应, 同时减色效应的强弱与金属离子的价态有关。随着价态升高, 减色效应增强。由此说明, 金属离子与DNA的作用使DNA的构象趋于缩拢; 且随着金属离子价态升高, 缩拢程度增强, 甚至产生缩合。还用现代多聚电解质理论对以上现象进行了讨论, 结果是令人满意的。     

Smart nano-architectures as potential sensing tools for detecting heavy metal ions in aqueous matrices

The discharge of heavy metal ions into water resources as a result of human activities has become a global issue. Contamination with heavy metal ions poses a major threat to the environment and human health. Therefore, there is a dire need to probe the presence of heavy metal ions in a more selective, facile, quick, cost-effective and sensitive way. Conventional sensors are being utilized to sense heavy metal ions; however, various challenges and limitations like interference, overlapping of oxidation potential, selectivity and sensitivity are associated with them that limit their in-field applicability. Hence, nanomaterial based chemical sensors have emerged as an alternative substitute and are extensively employed for the detection of heavy metal ions as a potent analytical tool. The incorporation of nanomaterials in sensors increases their sensitivity, selectivity, portability, on-site detection capability and device performance. Nanomaterial based electrodes exhibit enhanced performance because surface of electrode at nano-scale level offers high catalytic potential, large active surface area and high conductivity. Therefore, this review addresses the recent progress on chemical sensors based on different nanomaterials such as carbon nanotubes (CNTs), metal nanoparticles, graphene, carbon quantum dots and nanocomposites for sensing heavy metals ions using different sensing approaches. Furthermore, various types of optical sensors such as fluorescence, luminescence and colorimetry sensors have been presented in detail.     

Physicochemical Studies on Some Phenolic Polymer-Transition Metal Complexes in Nonaqueous Media

The formation of complexes between phenolic oligomer/polymer with some transition metal ions has been studied by conductance and emf measurements. Sharp changes in color, conductance, and potential at definite stoichiometric quantities of ligand and metal ions have been attributed to polymer-metal chelation. Interpretations of the results have been sought in terms of the length of the polymer chain and the nature of the transition metal ions.     

Thin Layer Chromatography of Purines on Silica Gel G Impregnated with Transition Metal Ions; Assay of Caffeine and Theophylline in Pharmaceutical Formulations

This study was undertaken to develop thin layers of silica gel G impregnated with transition metal ions for separation, identification and estimation of purines. The influence of transition metal ions and eluting solvents on chromatographic behaviour (hR_f) has been studied. The method was applied for qualitative analysis of purines in the mixtures and quantitative analysis of purine bases in the mixture as well as in pharmaceutical formulations. The results were compared statistically with those obtained by official methods. The method is simple, reproducible, and accurate within 1.3 ± 0.6%.