卡尔曼滤波荧光分析法用于铝,镓的同时测定

研究了SPAEC荧光螯合反应并结合卡尔曼滤波校正的高灵敏度高选择性荧光分析法.在荧光分析中首次用卡尔曼滤波以分辨铝、镓与SPAEC螯合物的重叠峰;提出了适于荧光分析的几种滤波方式,并讨论了各自的特点.该法用于铝与镓(1:40～14:1)混合物分析,改善了灵敏荧光法(及试剂)的选择性.     

新萤光试剂SPAEC与铝(Ⅲ)的配合反应及分析应用研究

用新合成的萤光试剂2-(5＇-磺基-2＇-羟基苯-1＇-偶氮)-5-乙氨基-4-甲酚(SPAEC)研究了荧光光度法测定铝的反应条件。铝(Ⅲ)与试剂在pH4.0～5.5的乙酸/乙酸钠缓冲介质中形成1:1型红色配合物并呈现荧光,其最大激发/发射波长为λ_(ex)/λ_(em)=535(520)/575nm。建立了0.05～3.01μol/L铝的荧光测定方法,考察了共存离子的干扰及消除方法,并试用于人工合成样及合金样的分析。     

新荧光试剂SPAEC与镓的螯合反应及分析应用

用新荧光试剂2-(5′-磺基-2′-羟基苯-1′-偶氮)-5-乙氨基-4-甲酚研究了荧光测定镓的反应条件,建立了测定15×10^-3～150×10^-3ppm镓的荧光方法,分析结果尚好。     

水杨醛异烟酰腙与镓荧光反应的研究

本文研究了荧光新试剂水杨醛异烟酰腙与镓的荧光反应,用紫外光谱法测定了试剂离解常数。在此荧光体系中,荧光配合物λ_(ex)=395nm、λ_(em)=480nm。在pH3.8、60％(V/V)乙醇介质中,测定的线性范围为0～1.0 μg/10mL,方法灵敏度为4×10~(-4)ppm。用荧光法测定了配合物的组成比及表观稳定常数。建立了镓的新荧光光度法,将其用于地质样品分析,精密度和准确度良好。     

2,4-二羟基苯甲醛缩4-氨基安替比林的合成及与铝的荧光反应

合成了新荧光试剂 2 ,4 二羟基苯甲醛缩 4 氨基安替比林 (2 ,4 DHBAAP) ,并测定其结构。基于铝 (Ⅲ )与 2 ,4 DHBAAP CTMAB形成配合物 ,导致体系荧光增敏的特性 ,提出了一种测定微量铝的新荧光方法。在pH 4 .5～ 6 .0的乙酸铵缓冲溶液及CTMAB存在下 ,铝 (Ⅲ )与DHBAAP形成 1∶1的配合物。在λex λem =385 5 15nm处 ,体系产生的荧光增敏程度最大 ,铝量的线性范围为 0～ 15 0 μg·L-1,检出限为 0 .2 μg·L-1。方法用于水样中铝的测定 ,结果满意     

荧光镓的电化学行为及稀土—荧光镓络俣吸附波研究

本文研究了荧光镓在PH2－10底液中的伏安行为，证实其偶氮基首先还原为氢化偶氮、，然后通过氢化偶氮的歧化反应或二电子还原生成相应的胺化物，荧光镓在汞电极上的吸附符合Frumkin等温式，在PH9．5的氯性底液中可获得稀土－荧光镓的络合吸附波,对重稀土的检测限为1．0×10^-8mol/L，测定了电活性络合物的组成及发光材料BaFCl:Ho中钬的含量。     

铝-水杨醛苯甲酰腙荧光反应的研究及应用

本文研究了Al~(3+)-水杨醛苯甲酰腙高灵敏度荧光体系,络合物的荧光激发波长=375nm,发射波长=450nm。铝量在0～1.4μg/10ml范围内,荧光强度与其含量成正比,灵敏度为0.4ppb。方法可用于试剂中微量铝的检测,结果令人满意。     

铁-荧光镓极谱络合吸附波的研究

在 p H6.1 0的 0 .1 mol/L ( CH2 ) 6 N4-HCl底液中 ,用单扫示波极谱法可获得铁( ) -荧光镓体系灵敏的络合吸附波。在 1 .0× 1 0 - 7～ 7.0× 1 0 - 6 mol/L范围内 ,铁浓度与波高呈线性关系 ,检测限达 7.0× 1 0 - 8mol/L,已成功地应用于金属镁粉中的铁和铝的测定 ,并测得电活性络合物的组成为铁∶荧光镓 =1∶ 1 ,条件形成常数β=3 .2× 1 0 4,表面电极反应速率常数 ks为 2 .9s- 1 。     

新荧光试剂5-(4'-卤代-2'-羧基苯偶氮)绕丹宁的合成及分析化学特性研究

合成了三种新荧光试剂,5-(4'-氯-2'-羧基苯偶氮)绕丹宁(CRACP.2).5-(4'-溴-2'-羧基苯偶氮)绕丹宁(BRACP,3)及5-(4'-碘-2'-羧基苯偶氮)绕丹宁(IRACP,4).研究了它们的吸收光谱及荧光性质.探讨了分子结构与荧光性能的关系.建立了铜(Ⅱ)的荧光分析方法.在pH5.3时.CRACP与铜( Ⅱ) 形成荧光螯合物, λ~ e~ x/ λ~e~m=310nm/408nm.检测限为5×10^-^4μg/g.     

以meso-四(N-甲基-3-吡啶基)卟啉荧光光度测定痕量锌的研究

研究了以meso-四(N-甲基-3-吡啶基)卟啉测定锌痕量锌的荧光光度法, 其灵敏度较其它水溶性卟啉衍生物测定锌的分光光度法要高, 检出量为1ppb, 线性范围为0-1.0μg/25mL. 方法已用于测定自来水和头发中的微量锌, 结果满意.     

新Schiff碱SAAQ的合成及其分析应用研究(Ⅰ)——荧光光度法测定镓

常用于测定镓的荧光试剂有8-羟基喹啉类、Schiff碱类、偶氮类及黄酮类等^[1～8]。而水杨醛缩-8-氨基喹啉(简称SAAQ)的合成及分析应用研究尚未见报道.本文研究了该试剂的合成方法及其分析应用.     

Microchip separations of transition metal ions via LED absorbance detection of their PAR complexes

Micellar electrokinetic chromatography was utilized in the electrophoretic separation of seven transition metal ions, colorimetrically complexed by 4-(2-pyridylazo)resorcinol (PAR) on a glass capillary electrophoresis microchip. Detection of the PAR metal chelates was demonstrated using a green light emitting diode (540 nm) and a miniature photomultiplier tube. Parameters investigated included the effect of buffer type, pH and surfactant concentration (sodium dodecyl sulfate, SDS) on the separation efficiency. The optimally determined background electrolyte contained 10 mM ammonium phosphate buffer (pH 7.5), 1 mM PAR to prevent kinetic lability problems and 75 mM SDS for enhanced resolution. The separation of seven transition metal ions, Co2+, V3+, Ni2+, Cu2+, Fe2+, Mn2+ and Cd2+, was achievable in under 65 s, with the resolution of each metal ion in excess of 1.60. Detection limits obtained ranged from 400 ppb for Ni2+ to 1.2 ppm for Mn2+.     

A fluorimetric method for the determination of traces of gallium

A fluorimetric method for the determination of gallium, based on the formation of a fluorescent 1:1 chelate with benzyl-2-pyridylketone-2-pyridylhydrazone, is described. In 90% ethanol, the fluorescent species has excitation and emission maxima at 469 and 545 nm, respectively, and the calibration graph is linear over the range 1.4–350 ppb Ga at pH 5. Methods of removing interferences are discussed.     

On-column complexation of metal ions using 2,6-pyridinedicarboxylic acid and separation of their anionic complexes by capillary electrophoresis with direct UV detection

On-column complexation of metal ions with 2,6-pyridinedicarboxylate (2,6-PDC) to form anionic complexes enabled their separation by capillary zone electrophoresis with direct UV detection at 214 nm. Nine metal ions, Cu2+, Zn2+, Ni2+, Cd2+ Mn2+, Pb2+, Fe3+, Al3+ and Ca2+, were determined in less than 7 min using 10 mM 2.6-PDC solution containing 0.75 mM tetradecyltrimethylammonium bromide at pH 4.0. Satisfactory working ranges (20-300 microM), detection limits (3-10 microM) and good repeatability of the peak areas (RSD 2.1-4.2%, n=5) were obtained using hydrodynamic injection (30 s). The proposed method was used successfully for the determination of Mn2+, Fe3+, Al3+ and Ca2+ in groundwaters.     

吡咯并[2,1,5-cd]中氮茚酰腙衍生物的合成及Cu2+荧光探针行为

设计合成了吡咯并[2,1,5-cd]中氮茚酰腙衍生物6. 测试了其紫外光谱和荧光光谱, 研究了其对铜离子的选择性识别作用. 结果表明, 化合物6作为铜离子荧光探针, 受常见离子干扰较小, 对于铜离子有着较高的选择性和较低的检出限.     

Preparation and characterization of thiacalix[4]arene coated water-soluble CdSe/ZnS quantum dots as a fluorescent probe for Cu2+ ions

Highly fluorescent water-soluble CdSe/ZnS (core/shell) quantum dots (QDs) as a fluorescent Cu2+ ion probe were synthesized using thiacalix[4]arene carboxylic acid (TCC) as a surface coating agent. Hydrophobic trioctylphosphine oxide (TOPO) capped CdSe/ZnS QDs were overcoated with TCC in tetrahydrofuran at room temperature, and deprotonation of the carboxyl groups of TCC resulted in the formation of water-soluble QDs. The surface structure of the QDs was characterized by using transmission electron microscopy (TEM) and fluorescence correlation spectroscopy (FCS). TEM images showed that TCC-coated QDs were monodispersed with the particle size (core-shell moiety) of approximately 5 nm. Hydrodynamic diameter of the TCC-coated QDs was determined to be 8.9 nm by FCS, showing that the thickness of the surface organic layer of the QDs was approximately 2 nm. These results indicate that the surface layer of TCC-coated QDs forms a bilayer structure consisting of TOPO and TCC molecules. TCC-coated CdSe/ZnS QDs were highly fluorescent (quantum yield, 0.21) compared to the QDs surface-modified with mercaptoacetic acid and mercaptoundecanoic acid. Fluorescence of the TCC-coated QDs was effectively quenched by Cu2+ ions even in the presence of other transition metal ions such as Cd2+, Zn2+, Co2+, Fe2+, and Fe3+ ions in the same solution. The Stern-Volmer plot for the fluorescence quenching by Cu2+ ions showed a linear relationship up to 30 microM of Cu2+ ions. The ion selectivity of TCC-coated QDs was determined by measurements of fluorescence responses towards biologically important transition metal ions (50 microM) including Fe2+, Fe3+, Co2+>Zn2+, Cd2+. The fluorescence of TCC-coated QDs was almost insensitive to other biologically important ions such as Na+, K+, Mg2+, and Ca2+, suggesting that TCC-coated QDs can be used as a fluorescent Cu2+ ion probe for biological samples. A possible quenching mechanism by Cu2+ ions was also discussed on the basis of a Langmuir-type adsorption isotherm.     

基于1,8-萘酰亚胺与罗丹明B间荧光共振能量转移的高选择性Hg2+比率荧光探针

以罗丹明B与1,8-萘二甲酰亚胺反应合成了1个高选择性Hg²⁺比率荧光探针(RN). 在甲醇/乙腈/4-羟基哌嗪乙磺酸缓冲溶液(pH=7.2, 体积比8:1:1)中, RN对Hg²⁺具有比色和比率荧光双重响应. 加入Hg²⁺后, RN的紫外-可见光谱在约556 nm处产生强吸收, 溶液由浅绿色变为橙色, 其它金属离子对RN的紫外-可见光谱几乎无影响. 无Hg²⁺存在时, RN的荧光光谱在540 nm处出现萘二甲酰亚胺荧光团的特征峰; 加入Hg²⁺后, 540 nm处的发射带逐渐消失, 同时在580 nm附近产生强荧光, 荧光颜色从绿色变为橙色. 这归因于从萘酰亚胺到开环罗丹明B的荧光共振能量转移(FRET), 探针RN对Hg²⁺的比率荧光响应具有高选择性, 不受其它共存金属离子的干扰.     

Aqueous solution speciation of Fe(III) complexes with dihydroxamate siderophores alcaligin and rhodotorulic acid and synthetic analogues using electrospray ionization mass spectrometry

Aqueous solutions of Fe3+ complexes of cyclic (alcaligin) and linear (rhodotorulic acid) dihydroxamate siderophores and synthetic linear eight-carbon-chain and two-carbon-chain dihydroxamic acids ([CH3N(OH)C=O)]2(CH2)n; H2Ln; n = 2 and 8) were investigated by electrospray ionization mass spectrometry (ESI-MS). Information was obtained relevant to the structure and the speciation of various Fe(III)-dihydroxamate complexes present in aqueous solution by (1) comparing different ionization techniques (ESI and FAB), (2) altering the experimental parameters (Fe3+/ligand ratio, pH, cone voltage), (3) using high-stability hexacoordinated Fe(III) siderophore complex mixtures (ferrioxamine B/ferrioxamine E) as a calibrant to quantify intrinsically neutral (H+ clustered or protonated) and intrinsically charged complexes, and (4) using mixed-metal complexes containing Fe3+, Ga3+, and Al3+. These results illustrate that for all dihydroxamic acid ligands investigated multiple tris- and bis-chelated mono- and di-Fe(III) species are present in relative concentrations that depend on the pH and Fe/L ratio.     

A ratiometric fluorescence probe for selective visual sensing of Zn2+

A simple ratiometric fluorescence probe based on vinylpyrrole end-capped bipyridine for the visual sensing of Zn2+ under aqueous physiological pH (6.8-7.4) is described. The fluorophores 3a-c showed strong emission around 537 nm in acetonitrile with a quantum yield of 0.4. In buffered (HEPES, pH 7.2) acetonitrile-water mixture (9:1 v/v), titration of transition metal salts to 3c showed strong quenching of the emission at 547 nm except in the case of Zn2+, which resulted in a red-shifted emission at 637 nm. Alkali and alkaline earth metal salts could not induce any considerable changes to the emission behavior of 3a-c. The binding of Zn2+ was highly selective in the presence of a variety of other metal ions. Though Cu2+ quenches the emission of 3c, in the presence of Zn2+, a red emission prevails, indicating the preference of 3c toward Zn2+. Job plot and Benesi-Hildebrand analysis revealed a 1:1 complexation between the probe and the metal ion. The selective visual sensing of Zn2+ with a red emission is ideally suited for the imaging of biological specimens.