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1.
一种新型三角架罗丹明B荧光探针对Cu~(2+)识别性能研究   总被引:1,自引:0,他引:1  
设计、合成了一种新颖的三角架结构罗丹明B衍生物(2).在乙醇-水(8/1,V/V)介质中,用Tris-HCl控制体系pH为6.8,观察到Cu2+对化合物2的荧光及紫外-可见吸收增强性能,同时化合物2对Cu2+具有较高的选择性响应.选择最大激发和发射波长为557/577nm,测定了探针2(1.00×10-5mol·L-1)对Cu2+响应的校准曲线,线性范围为0.10~10.00×10-5mol·L-1,相关系数R2=0.9964(n=15),检出限为1.129×10-7mol·L-1,平行测定5次的相对标准偏差(R.S.D.)为2.2%;以557nm为最大吸收波长测定紫外吸收,Cu2+响应的浓度线性范围为0.50~25.00×10-5mol·L-1,相关系数R2=0.9948(n=13),检出限为3.338×10-7mol·L-1.  相似文献   

2.
通过机械化学合成法合成了一种共价有机框架材料TpPa-1,以此作为电极材料制备化学修饰电极,研究了修饰电极的差分脉冲阳极溶出伏安法(DPASV)同时测定铜离子和汞离子。结果表明,TpPa-1/Nafion修饰电极在磷酸盐缓冲溶液中可实现对Cu^2+和Hg^2+的同时检测。Cu^2+的检出限为5.0×10^-8 mol/L线性范围为1.0×10^-7~5.0×10^-5 mol/L,R^2=0.9975。Hg^2+的检出限为1.0×10^-8 mol/L,线性范围为2.0×10^-8~1.0×10^-4 mol/L,R^2=0.9988。采用上述方法对实际样品进行检测,回收率为97.6%~105.5%,RSD均小于4.0%。  相似文献   

3.
硅基分子印迹技术制备铜离子选择电极   总被引:1,自引:0,他引:1  
以3-(2-氧基乙基氨基)丽基三甲氧基硅烷作为功能分子,铜离子为模板,将分子印迹技术与溶胶凝胶技术相结合,制备了铜离子选择电极,探讨了电极的响应机理.该电极对铜离子有较好的能斯特响应特性,其线性响应范围为5.00×10^-2~3.98×10^-6mol·L^-1,斜率为31.5mV/pC(-logc),检出限为1.00×10^-6mol·L^-1.同时该电极显示了较好的选择性,重现性和稳定性.  相似文献   

4.
镧和铕对蚕豆保卫细胞外向钾通道的作用   总被引:1,自引:0,他引:1  
薛绍武  杨频 《中国科学B辑》2009,39(11):1363-1367
研究了镧(La^3+)和铕(Eu^3+)对蚕豆保卫细胞外向钾通道(Kout^+)电流的作用.在细胞外,La^3+对Kout^+电流是抑制的,半抑制浓度EC50为81μmol·L^-1;Eu^3+对Kout^+电流表现为低浓度(10和50μmol·L^-1)激活,高浓度(≥1mmol·L^-1)抑制.La^3+在细胞内对Kout^+电流也表现为低浓度(1.13×10^-14 mol·L^-1)激活,高浓度(5.86×10^-14 mol·L^-1)抑制现象.稀土离子La^3+和Eu^3+对保卫细胞Kout^+电流的作用,可能和植物调节水分有关,这可能是稀土生物效应的机制之一.  相似文献   

5.
杜会枝  杨频 《中国化学》2006,24(3):345-349
Using the whole cell patch clamp technique, the effect of Cu^2+on transient outward K^+current (/to) and delayed rectifier K^+ current (Idr) was studied in acutely isolated rat hippocampal neurons.Ito and Idr were increased when the concentration of Cu^2+ was lower than 2 × 10^-5 and 10^-5 tool/L, respectively, and increased ratio was decreased with increasing Cu^2+concentration in the bath solutions. When the concentration continued to increase to 5× 10^-5 and 2 × 10^- 5 mol/L, the currents were hardly changed, while the concentration was more than 10^-4 and 5 × 10^-5 mol/L, the currents were inhibited remarkably. Cu^2+ (10^-5 mol/L) did not affect the activation and inactivation process of Ito. The activation curve of Idr was shifted toward positive potential, but 10^-5 mol/L Cu^2+did not affect slope factor. According to these results, it was considered that Cu^2+at low concentration in the bath solution could promote Ito and Idr while at high concentration could inhibit them, and change of amplitude was different with different membrane voltage. Conclusion was drawn: Cu^2+may be involved in the pathophysiologic mechanism of diseases with neuropathological components.  相似文献   

6.
基于白藜芦醇对鲁米诺-铁氰化钾化学发光反应的增敏作用,对其最佳反应条件进行了系统试验,并结合流动注射,提出了测定红葡萄酒中白藜芦醇含量的流动注射化学发光法。在1×10^-3 mol·L^-1氢氧化钠溶液中,鲁米诺溶液及铁氰化钾溶液的最佳浓度依次为8×10-6,2×10^-5 mol·L^-1。在此条件下,白藜芦醇的线性范围为1.00×10-8~1.00×10^-6 mol·L^-1,检出限(3S/N)为3.0×10^-9 mol·L^-1。对4.00×10^-7 mol·L^-1白藜芦醇标准溶液进行精密度试验,测定值的相对标准偏差(n=11)为2.6%。分析实际样品时,将红葡萄酒样品减压抽滤除去不溶性颗粒,取滤液50mL,煮沸2min,除去挥发性芳香物质,冷却后离心5min,取上清液按仪器工作条件进行测定。按此方法在样品的基础上进行加标回收试验,测得回收率为95.9%~130%。  相似文献   

7.
制备了一种以普鲁卡因与单质碘形成的缔合物为电活性物的全固态碳糊普鲁卡因电极,利用该电极对普鲁卡因的响应测定普鲁卡因注射液中普鲁卡因的含量。电极的线性响应范围为3.5×10^-5~0.1mol/L,线性回归方程为E=57.01gc+102.2,相关系数r=0.999,检出限为2.5×10^-5mol/L。盐酸普鲁卡因的回收率在96.1%~104.3%之间,测定结果的相对标准偏差为1.86%-2.30%(n=5)。该电极响应迅速,重现性好。用该电极测定了盐酸普鲁卡因注射液中普鲁卡因的含量,测定结果与药典法测定结果相符。  相似文献   

8.
研究了甲酸在二十四面体Pt纳米晶(THHPtNCs)电极表面解离吸附反应过程.电化学原位红外反射光谱结果显示,甲酸在低电位(-0.20V(SCE))即可在THHPtNCs电极上氧化到CO2,同时发生分子内化学键断裂生成吸附态CO物种.运用程序电位阶跃暂态方法定量研究甲酸解离吸附反应动力学,测得5×10^-3mol·L^-1 HCOOH+0.1mol·L^-1 H2SO4溶液中甲酸在THHPtNCs电极上解离吸附的最大平均速率υamax为13.19×10^-10mol·cm^-2·s^-1,是商品Pt/C催化剂电极上υamax的1.5倍.研究结果揭示了THHPtNCs的反应活性显著高于Pt/C催化剂.  相似文献   

9.
唐明宇袁若  柴雅琴 《中国化学》2006,24(11):1575-1580
The third generation amperometric biosensor for the determination of hydrogen peroxide (H2O2) has been described. For the fabrication of biosensor, o-aminobenzoic acid (oABA) was first electropolymerized on the surface of platinum (Pt) electrode as an electrostatic repulsion layer to reject interferences. Horseradish peroxidase (HRP) absorbed by nano-scaled particulate gold (nano-Au) was immobilized on the electrode modified with polymerized o-aminobenzoic acid (poABA) with L-cysteine as a linker to prepare a biosensor for the detection of H2O2. Amperometric detection of H2O2 was realized at a potential of +20 mV versus SCE. The resulting biosensor exhibited fast response, excellent reproducibility and sensibility, expanded linear range and low interferences. Temperature and pH dependence and stability of the sensor were investigated. The optimal sensor gave a linear response in the range of 2.99×10^-6 to 3.55×10^-3 mol·L^-1 to H2O2 with a sensibility of 0.0177 A·L^-1·mol^-1 and a detection limit (S/N = 3) of 4.3×10^-7 mol·L^-1. The biosensor demonstrated a 95% response within less than 10 s.  相似文献   

10.
研究了以达旦黄(TY)作为共振光散射探针测定市售药品中丁胺卡那霉素(AMK)的测定方法.该方法基于在pH=5.5的Britton—Robinson缓冲溶液中,达旦黄和丁胺卡那霉素结合后有强烈的共振光散射作用.在λ=482nm处,共振光散射强度(△IRLS)最大且光散射的强度与AMK的浓度在0.4~2.4mg·L^-1范围内成正比(相关系数r=0.9986),检出限为8.6×10^-3mg·L^-1.该方法简便、快速、灵敏,对1.0mg·L^-1的AMK溶液平行测定11次,RSD=2.57%.用于市售样品的分析测定,结果满意。  相似文献   

11.
The sol-gel derived glucose biosensor was developed, and the sol-gel membrane was organically modified by N-(3-triethoxysilylpropyl)-ferrocenylmethylamine (FcSi) as sol-gel precursor to make electrochemical biosensor. The structure of biosensor was sol-gel/FcSi+GOx/GC type (glucose oxidase, GOx). The ferrocene mediator was chemically immobilized to the silane network, and GOx was entrapped to the sol-gel glass network. Therefore, these structures prevented mediator leakage and retained the enzyme activity. Additionally, pH of electrolyte, temperature effects, and interference of positive substances with biosensor were investigated. And the electrochemical performance of biosensor was studied by amperometry. The results indicated that the linear range, detection limit. and response slope of biosensor was 2.00×10^-4-1.57×10^-3 mol·L^-1, 2.0×10^-4 mol·L^-1 and 5.06×10^5 nA·mol^- 1·L, respectively.  相似文献   

12.
研究了一种用铅笔芯制作的微电极的电化学行为,并利用这种电极进行抗坏血酸含量的测定。结果表明:在5.0×10^-5~1.0×10^-2mol/L的浓度范围内,抗坏血酸的氧化峰电流与其浓度呈线性关系,相关系数/=0.9993,检出限为2.5×10^-5mol/L(S/J7v=3)。对2.5×10^-3mol/L抗坏血酸溶液平行测定6次,测定结果的相对标准偏差为4.7%。该电极用于维生素c片中抗坏血酸含量的测定,加标回收率为94.8%-99.8%。  相似文献   

13.
刘宁高伟  宋俊峰 《中国化学》2006,24(11):1657-1661
Voltammetry using solid electrodes usually suffers from the contamination due to the deposition of the redox products of analytes on the electrode surface. The contamination has resulted in poor reproducibility and overelaborate operation procedures. The use of the chemical catalysis of oxidant on the reduction product of analyte not only can eliminate the contamination of analyte to solid electrodes but also can improve the faradaic response of analyte. This work introduced both the catalysis of oxidant K2S2O8 and the enhancement of surfactant Triton X-100 on the faraday response of amiodarone into an adsorptive stripping voltammetry at a carbon paste electrode for the determination of amiodarone. The method exhibits high sensitivity, good reproducibility and simple operation procedure. In 0.2 mol·L^-1 HOAc-NaOAc buffer (pH=5.3) containing 2.2×10^-2 mol·L^-1 K2S2O8 and 0.002% Triton X-100, the 2.5th-order derivative stripping peak current of the catalytic wave at 0.3 V (vs. Ag/AgCl) is rectilinear to amiodarone concentration in the range of 2.0×10^-10-2.3×10^-8 mol·L^-1 with a detection limit of 1.5×10^-10 mol·L^-1 after accumulation at 0 V for 30 s.  相似文献   

14.
N-乙酰-L-半胱氨酸在咖啡酸修饰碳糊电极上的电催化氧化   总被引:1,自引:1,他引:0  
研究了N-乙酰-L-半胱氨酸(N-acetyl-L-cysteine,NAC)在咖啡酸(CFA)修饰碳糊电极(CFA/CPE)上的电催化行为。结果表明,NAC在裸碳糊电极(CPE)上的直接电化学氧化过程十分迟缓,而CFA/CPE对NAC的电化学氧化具有良好的催化作用。用循环伏安法(CV)、计时电流法(CA)测定了NAC在CFA/CPE上的电极过程动力学参数。电荷传递系数α=0.79,电催化氧化反应速率常数k=(4.40±0.10)×10^3(mol.L^-1)^-1.s^-1。用微分脉冲伏安法(DPV)测得催化氧化峰电流与NAC浓度在1.0×10^-6~7.5×10^-4mol.L^-1范围内呈良好的线性关系,线性回归方程为Ipa(μA)=4.075c(mmol.L^-1)+2.671,r=0.9988,检出限为1.7×10^-7mol.L^-1。用该方法对市售药品富露施中的NAC含量进行测定,结果令人满意。  相似文献   

15.
研制了电聚合L-半胱氨酸修饰玻碳电极,采用循环伏安法研究了L-酪氨酸在此修饰电极上的电化学行为。利用线性扫描循环伏安法对L-酪氨酸进行定量分析,L-酪氨酸的线性范围为2.0×10^-8~2.0×10^-5 mol·L^-1,检出限为7.9×10^-10 mol·L^-1。结果表明,此修饰电极具有良好的选择性、重现性和稳定性,对L-酪氨酸的电催化性能良好,可用于人尿中L-酪氨酸的测定,回收率为98.3%~109.8%。  相似文献   

16.
荧光猝灭法测定替硝唑的含量   总被引:1,自引:0,他引:1  
B-R缓冲溶液中,替硝唑可使十二烷基硫酸钠(SDS)的荧光猝灭,据此建立了荧光猝灭法测定替硝唑含量的方法.实验结果表明:在pH5~8缓冲溶液中,替硝唑浓度在0.2~5.0 mg·L^-1范围内与体系的荧光猝灭强度呈现良好的线性关系(R=0.998 4),对浓度为0.2 mg·L^-1的替硝唑平行测定11次,检出限为6.4×10^-3mg·L^-1,RSD=1.91%,该法简便,快速,用于药物制剂中替硝唑含量的测定,结果满意.  相似文献   

17.
在二元配合物巴洛沙星-Tb^3+中加入ATP,Tb^3+在其特征波长545nm处的荧光强度增强,据此建立了新的巴洛沙星Tb^3+-ATP荧光体系。在最优化实验条件下,增强的荧光强度与ATP的浓度呈良好的线性关系,线性范围为2.0×10^-6-3.0×10^-5mol/L,检出限为8.0×10^-7mol/L。详细的机理研究表明,ATP能与巴洛沙星-Tb^3+形成大的三元络合物荧光体系。新建立的荧光体系成功地应用于ATP注射液中ATP的定量检测。对不同批次ATP注射液进行加标回收试验,回收率为101%-106%,测定结果的相对标准偏差为1.1%-1.9%(n=5)。  相似文献   

18.
以1,3-二苯基异苯并呋喃(1,3-Diphenylisobenzofuran,DPBF)为荧光探针,研究了姜黄素(Curcumin,CUR)在铜离子催化下产生的单线态氧(^1O2),其反应机理为姜黄素与溶液中的氧分子快速作用产生O2^·-和H2O2等活性氧物种,同时Cu^2+与姜黄素形成复合物,再与H2O2形成过氧化物过渡态,过氧化物进一步与H2O2发生类Haber-Weiss反应生成^1O2,且只有Cu^2+和Cu^+离子可催化姜黄素并产生^1O2.^1O2在1.37×10^-2~3.66×10^-7mol/L浓度范围内与荧光强度下降值△IF有良好的线性关系。检出限为4.12×10^-4mol/L。  相似文献   

19.
Silver (Ag) nanoparticles were directly electrodeposited on multi-walled carbon nanotubes (MWCNT) in AgNO3/LiNO3 containing EDTA (ethylenediaminetetraacetic acid). The structure and nature of the resulting Ag/MWNT composite were characterized by field emission scanning electron microscopy (FE-SEM), transmission electron microscopy (TEM) and X-ray diffraction (XRD), and the distribution shape of Ag nanoparticles was found to be dependent on the presence of EDTA. The modified electrode showed excellent electrocatalytic activity to redox reaction of hydrogen peroxide and the mechanism of hydrogen peroxide was partly reversible procession with oxidation and reduction peaks at 0.77 and -0.83 V, respectively. The oxidation and reduction peak currents were linearly related to hydrogen peroxide concentration in the range of 1×10^-6-3×10^-4 and 1 ×10^-8-7× 10^-4 mol·L^-1 with correlation coefficients of 0.996 and 0.986, and 3s-detection limit of 9 × 10^-7 and 7 × 10^-9 mol·L^-1.  相似文献   

20.
铁氰酸镍膜修饰金电极的研制及应用   总被引:1,自引:0,他引:1  
通过层层组装的方法,将Ni^2+和[Fe(CN)6]^3-交替沉积在巯基乙酸功能化的金电极表面.首次成功制备了铁氰酸镍多层膜修饰电极,用循环伏安法研究了该多层膜的电化学行为,实验表明峰电流随膜层数的增加而增加,膜均匀增长.该修饰电极对一价金属离子Na^+,K^+,NH4^+具有选择性响应,尤其对K^+存在准能斯特响应,响应范围0.01~1.0mol/L;而且该电极对抗坏血酸(AA)和S2O3^2-体系的氧化具有良好的电催化作用,线性范围分别为:1.14×10^-4~1.14×10^-3mol/L和5.0×10^-4~3.1×10^-3mol/L.  相似文献   

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