共查询到20条相似文献,搜索用时 78 毫秒
1.
2.
3.
建立了以三联吡啶钌为发光体系的毛细管电泳电化学发光(CE-ECL)检测系统,并应用于分离和测定西咪替丁片剂中西咪替丁的含量。考察了检测电位,三联吡啶钌(Ru(bpy)32+)的溶液浓度,缓冲液的pH和溶液浓度,分离电压、进样电压与进样时间等因素对分离检测的影响。结果表明:在检测电位1.18V,Ru(bpy)32+溶液浓度为5 mmol/L,磷酸盐缓冲液(PBS)25 mmol/L(pH 7.8),进样时间10 s,进样电位10 kV,运行电位15 kV下,测得西咪替丁线性范围为2.8×10-6~4.0×10-4mol/L,检出限为1.2×10-7mol/L(S/N=3)。对1.0×10-5mol/L的西咪替丁标准溶液连续测定5次,电化学发光强度和迁移时间的RSD分别为3.9%和1.5%。方法已应用于西咪替丁片剂中西咪替丁含量的测定。 相似文献
4.
5.
建立了毛细管电泳-电化学发光(CE-ECL)法检测泛昔洛韦的新方法。考察了检测电位、运行高压、进样电压与时间、检测池中磷酸盐的pH值、运行缓冲溶液的pH值及浓度等测试条件对电化学发光强度的影响。在最优化的实验条件下,泛昔洛韦在5.0×10-6~2.5×10-4mol/L浓度范围内与电化学发光强度有良好的线性关系,相关系数为0.9973,检出限为3.5×10-6mol/L。该法灵敏度高,选择性好,可应用于泛昔洛韦原料药及制剂的质量控制。初步探讨了CE-ELC检测泛昔洛韦的机理。 相似文献
6.
联吡啶钌电化学发光传感器测定海洛因 总被引:1,自引:0,他引:1
利用离子液体为粘合剂制作碳糊电极,采用高分子聚合法,合成包埋有Ru(bpy)2(dcbpy)2+的高分子聚合物,将钌聚合物掺杂于离子液体碳糊电极中,制作电化学发光传感器.结果表明,此传感器具有很好的电化学发光特性,与用石蜡油为粘合剂制作的电化学发光传感器相比,离子液体为粘合剂的电化学发光传感器检测三丙胺的检出限降低1个数量级.海洛因对电化学发光传感器的发光信号有很好的增强作用,基于此建立了高灵敏度检测海洛因的电化学发光分析法,海洛因浓度与电化学发光信号在2.0×10-9~2.0×10-5 mol/L范围内呈良好的线性关系,检出限为8×10-10 mol/L (S/N=3).将电化学发光传感器在5.0×10-9 mol/L海洛因溶液中采用线性循环电位连续扫描60圈,相对标准偏差小于2.2%.本方法用于血清中海洛因的检测,其回收率为94%~101%. 相似文献
7.
8.
9.
10.
光电化学传感器以光作为激发源,以光电流或光电压作为检测信号,具有响应快速、灵敏度高、设备简单等特点,目前已在环境、食品、医学等多个领域的分析测试中得到广泛应用。该文阐述了光电转换材料与光电化学传感器的制备方法,介绍了光电化学传感器的原理和分类。光电化学传感器包含光寻址电位型传感器和电流型光电化学传感器,其中,电流型光电化学传感器由于优良的光电性能、检出限低、所需材料低廉且易加工等优势而被广泛应用。文中着重介绍了电流型光电化学传感器在金属离子、有机污染物、核酸、蛋白质、细胞等方面的应用,并对光电化学传感器的发展前景进行了展望。 相似文献
11.
本文合成了一种多联吡啶钌配合物(bpy)2Ru(phenCl4)(PF6)2,bpy为2,2′-联吡啶, phenCl4为3,4,7,8-四氯-1,10-邻菲罗啉,并用元素分析、红外光谱、核磁共振谱对其结构进行了表征。此化合物在紫外和可见光区都有吸收,在可见光区的最大吸收波长是440nm,这是典型的金属到配体(MLCT)的跃迁,其光致发光性能也显示出MLCT迁移特征,并且随溶剂不同,其最大发射波长从630nm变化到649nm。值得注意的是,此配合物的电致化学发光性能受pH影响不大,这与传统的随pH增大电致化学发光强度增大的联吡啶钌不同,尤其在强碱条件下,其背景电致化学发光很小。 相似文献
12.
An amide-linked 2,6-bis{[(2-hydroxy-5-tert-butylbenzyl)(pyridyl-2-methyl)-amino]-methyl}-4-methylphenol-ruthenium(II) tris(bipyridine) 2PF6− complex, 1, was first used to recognize Co(II) in EtOH/H2O (1:1, v/v) solution, with the ruthenium(II) tris(bipyridine) moiety selected as a fluorophore and the multi-substituted phenol unit chosen as a receptor. The fluorescence quenching of 1 was attributed to the formation of an inclusion complex between multi-substituted phenol unit and Co(II) by 1:1 complex ratio (K = 2.5 × 105), which has been utilized as the basis of the fabrication of the Co(II)-sensitive fluorescent chemosensor. The analytical performance characteristics of the proposed Co(II)-sensitive chemosensor were investigated. The sensor can be applied to the quantification of Co(II) with a linear range covering from 1.0 × 10−7 to 5.0 × 10−5 M and a detection limit of 5 × 10−8 M. The experiment results show that the response behavior of 1 to Co(II) is pH-independent in medium condition (pH 4.5–9.5) and show excellent selectivity for Co(II) over transition metal cations except Cu(II). The chemosensor has been used for determination of Co(II) in water samples. 相似文献
13.
Photocurrent generation from CdSe/ZnS (core/shell) quantum dots (QDs) in a photoelectrochemical cell was proposed to perform a bioaffinity biosensor in this study. The photocurrent of QDs is reversible and methylene blue as an electron transfer mediator causes a four‐fold increase in the photocurrent. We further present quantitative photoelectrochemical detection of biotin conjugated QDs on the avidin immobilized ITO electrodes. A linear calibration graph was obtained in the range of 4 and 18 nM of biotin conjugated QDs with a coefficient of determination of 0.997. Results imply that QDs can be successfully used as photoelectroactive labels for the photoelectrochemical biosensor systems. 相似文献
14.
设计合成了一种具有D-π-A结构的三苯胺功能染料(TCA),并通过分子结构中的羧基将其配位于TiO_2纳米粒子修饰的光电极表面,发展了一种可在超低电位下高灵敏检测谷胱甘肽(GSH)的光电传感方法.该TCA分子以三苯胺为电子给体,噻吩为桥连基团,氰基乙酸为电子受体.在可见光的照射下,TCA通过分子内电子转移将光电子由三苯胺经噻吩和羧基注入到TiO_2的导带能级,进而注入基底光电极,产生阳极光电流;同时,TCA被氧化到氧化态.由于氧化态TCA的稳定性好,可循环被生理活性小分子GSH还原,并产生放大的阳极光电流.TCA功能化的TiO_2纳米粒子修饰电极对GSH表现出了极高的催化活性,在波长为480 nm的可见光照射下,在0 V的超低电位下即可实现对GSH的催化氧化.基于这一性质,发展了一种可用于GSH检测的光电传感方法.在最优条件下,该传感器对浓度为2~100μmol/L和0.1~2.4 mmol/L的GSH具有良好的线性响应,检出限低达1μmol/L.此外,该光电传感器具有较好的选择性,可排除13种氨基酸和生理活性物质多巴胺及氢醌的干扰,因此具有一定的实际应用前景. 相似文献
15.
Mahmoud M. Khader Mahmoud M. Saleh Emad M. El-Naggar 《Journal of Solid State Electrochemistry》1998,2(3):170-175
Active ferric tungstate was prepared by fusing an equimolar mixture of tungsten oxide and ferric oxide at 1100 °C and annealing
at 800 °C for 20 h. Analysis of the electrode material by X-ray diffraction showed that its composition was Fe2WO6. When this material was illuminated by visible light in 0.1 M NaOH solution, an anodic photocurrent at a positive potential
of 0.5 V (SCE) was obtained. Therefore, this material is considered as an n-type semiconductor. The d.c. conductivity of this
material at 25 °C was 4 × 10−6 Ω−1 cm−1. In the dark, unexpectedly high anodic currents were observed at positive potentials of 0.8 V (SCE) in 0.1 M NaOH. These
currents are attributed to the existence of a high density of electron-hole recombination centers within the band-gap of ferric
tungstate. When dimethyl viologen (DMV) was used as an electroactive compound in the electrolyte, the anodic photocurrents
increased significantly. The oxidation of DMV is thus expected to compete with the electron-hole recombination process. Furthermore,
the process of electron-hole recombination was also predicted from the shape of the photocurrent transients under interrupted
illumination. These transients exhibited first-order relaxation effects in the region of the onset time of the photocurrents.
The band-gap energy of Fe2WO6 was found to be about 1.5 eV and its flat-band potential in 0.1 M NaOH was about −0.3 V (SCE). The photoelectrochemical properties
of ferric tungstate are explained according to the formalism of the band model of the semiconductor/electrolyte interface.
Received: 16 July 1997 / Accepted: 26 September 1997 相似文献
16.
Lo?&#x;c J. CharbonnièreRaymond Ziessel 《Tetrahedron letters》2003,44(33):6305-6307
The synthesis of tris[3-(6-carboxypyridin-2-yl)pyrazol-1-yl]methane is described in a linear multi-step protocol. The pyridyl-pyrazolyl arms are first constructed before being condensed with chloroform. Careful study of the condensation reaction shows the presence of an isomeric form of the tris(pyrazolyl)methane derivative in which one of the pyrazolyl substituents is linked through the nitrogen atom at the 2 position of the pyrazol. After acid-catalysed isomerisation to the desired isomer, the intermediate compound was subjected to a carboalkoxylation reaction and a subsequent hydrolysis. These are some rare examples of reactions directly occurring on the tris(pyrazolyl)methane platforms. 相似文献
17.
《Journal of Coordination Chemistry》2012,65(1):79-88
Abstract The preparation and characterisation of salts of the complex cation cis-bis(2,2′-bipyridine)-chloro(dimethylsulfoxide-S)ruthenium(IIII), [Ru(bpy)2Cl(dmso)]+, is reported. The complex was prepared by the reaction of 2,2′-bipyridine with RuCl3 · 3H2O in dimethylsulfoxide. The value of this complex arises from its ability to react with suitable bidentate ligands particularly those that could act as DNA intercalators. The structure of [Ru(bpy)2Cl(dmso)][ClO4] · 2H2O has been determined by single crystal X-ray diffraction. The complex crystallises in space group PI with a = 8.205(3), b = 10.448(4), c = 16.769(6) Å; α = 78.99(3)°, γ = 77.47(3)°, γ = 72.20(3)°, Z=2. The structure was refined by least-squares methods using 4070 observed reflections with 196 variable parameters (final R = 0.039). 相似文献
18.
Chi-Hang Lee 《Tetrahedron》2010,66(22):3897-3903
We describe an improved synthetic approach to access tripodal compounds with variable footprints and anchor groups. Two ruthenium(II) bipyridine tripodal complexes with three carboxylic acid groups in meta (Ru-m-COOH, 1) and para (Ru-p-COOH, 2) positions, and with large (180-250 Å2) footprints were synthesized and bound to the surface of nanostructured TiO2. Selected properties of 1 and 2 in solution and bound are reported. 相似文献
19.
生物样品中生物素的酶联免疫吸附分析两种包被方法的比较研究 总被引:2,自引:0,他引:2
通过对用猪肺炎霉浆菌包被或用其兔抗体包被两种方法的比较研究,得到一种高灵敏度和高准确度对生物样品中生物素含量直接定量的酶联免疫吸附分析(ELISA)法。猪肺炎霉浆菌包被法的检测限仅约为同类文献值的1/150,加标平均回收率为101.13%,均优于猪肺炎霉浆菌抗血清(抗体)包被法结果。表明猪肺炎霉浆菌比其抗体对酶标板有更强的物理吸附力。方法亦可用于其它待测定物的ELISA法。 相似文献
20.
生物素的微分脉冲极谱行为及其测定 总被引:6,自引:2,他引:6
用微分脉冲极谱法研究了生物素的电化学行为,用滴汞电极作工作电极,在01mol·L-1LiCl底液中,生物素的峰电位为-150V,生物素浓度在528~877μmol·L-1范围内与峰高呈线性关系。初步探讨了电极反应机理。该法应用于含生物素样品的分析,可以不经分离,直接测定,结果良好。 相似文献