以邻苯二胺为底物固体电极方波伏安法检测辣根过氧化物酶及其标记物

以玻碳电极为工作电极,研究了邻苯二胺(OPD)为底物伏安法检测辣根过氧化物酶(HRP)及其标记物的方法。HRP能够催化H_2O_2氧化OPD,其反应产物在玻碳电极上于-0.42V(vs.Ag/Agcl)左右产生一个灵敏的还原峰,峰电流随着HRP浓度的增大而增大,借助此还原电流可以测定HRP,并进而可用于以HRP为标记物的电化学酶免疫分析。用方波伏安法对酶催化反应条件和酶催化反应产物的测定条件进行了详细的研究,在最佳条件下测定游离HRP的线性范围是1.0×10~(-10)～4.0×10~(-9)g/mL,检出限为8.5×10~(-11)g/mL;对游离的酶标记物(IgG-HRP)的测定最大稀释比为1:2000000。     

甲基红-H2O2-HRP伏安酶联免疫分析法测定HRP及其标记物

提出了一种新的辣根过氧化物酶的底物-甲基红,它本身具有电化学活性,能够在静汞电极上发生还原反应,产生灵敏的伏安电流信号.以H2O2为氧化剂,HRP能催化氧化还原反应的发生,使甲基红被氧化分解,其平衡浓度降低,对应的还原峰电流降低,峰电流的降低值与HRP的质量浓度在5.0×10-8～5.0×10-7g/mL之间呈线性关系,对2.0×10-7g/mL HRP进行11次测定的相对标准偏差为4.6%,方法的检出限为1.8×10-8g/mL.应用于IgG-HRP和Avidin-HRP的测定.     

OAP-H2O2-HRP酶促产物的固体电极法研究及应用

采用电化学方法和紫外-可见光谱法对邻氨基酚(OAP)-H2O2-辣根过氧化物酶(HRP)酶联免疫分析体系的反应产物进行了较为详细地研究.紫外-可见光谱实验表明HRP的加入极大地催化了H2O2氧化OAP的反应.循环伏安实验结果表明,其酶促产物在玻碳电极上发生可逆的氧化还原反应,峰电流与扫描速率的平方根成线性关系;微分脉冲伏安曲线表明酶促产物在-0.336 V左右(一8.0 B-R缓冲溶液中)产生了1个峰形良好的还原峰,峰电流随HRP浓度的增大而增大,借助此还原电流可用于测定HRP.用微分脉冲伏安法对酶促产物的测定条件进行了优化.在最佳条件下测定游离HRP的线性范围为8.0×10-11～4.0×10-9-g/mL.检出限为6.9×10-11g/mL.     

以OT为底物固体电极伏安法测定辣根过氧化物酶及其标记物的研究

以玻碳电极为工作电极研究了邻联甲苯胺(OT)为底物微分脉冲伏安法测定辣根过氧化物酶(HRP)及其标记物的方法。HRP能够催化H2O2氧化OT,其反应产物在玻碳电极上-0.58V(vs.Ag/AgCl)左右被还原产生一个灵敏的还原峰,还原峰电流随着酶浓度的增大而增大,借助此还原电流可以测定HRP,并进而可用于以HRP为标记物的酶免疫分析。对酶催化反应条件和酶催化反应产物的测定条件进行了详细的研究,在最佳实验条件下测定游离HRP的线性范围是2.0×10-9～4.0×10-8g/mL,检出限为1.6×10-9g/mL;测定游离的酶标记物(IgG HRP),稀释范围为1∶2000～1∶400000,最大稀释比为1∶400000。     

以3,3′,5,5′-四甲基联苯胺为底物的伏安酶联免疫分析体系研究

对 3 ,3′,5 ,5′ 四甲基联苯胺 (TMB) H2 O2 辣根过氧化物酶 (HRP)伏安酶联免疫分析体系进行了研究。HRP催化H2 O2 氧化TMB ,其氧化产物在汞电极上可以发生还原反应 ,在B R缓冲溶液中 ,-0 .76V(vs.SCE)处产生较为灵敏的伏安波。将此伏安波应用于测定HRP和HRP的标记物。测定HRP的线性范围为 6.0×1 0 - 1 1 ～ 5 .0× 1 0 - 9g mL ,检测限为 5 .0× 1 0 - 1 1 g mL。对该体系酶催化反应机理及产物的电极还原过程进行了探讨     

酸性铬蓝K-H2O2-HRP伏安酶联免疫分析法测定HRP及其标记物

本文提出了一种新的辣根过氧化物酶(HRP)的底物--酸性铬蓝K(ACBK),它本身具有电化学活性,能够在汞电极上发生还原反应.以H2O2为氧化剂,HRP的加入能加快氧化反应的进行,使酸性铬蓝K被氧化分解,其平衡浓度降低,对应的还原峰电流降低,峰电流的降低值同HRP的加入量在8.0×10-8～1.0×10-6 g/mL之间呈线性关系.用于IgG-HRP的测定,最高稀释比为1∶5 000.     

基于血红蛋白的过氧化物酶特性测定其在血浆中游离态含量

基于血红蛋白 (Hb)的过氧化物酶特性 ,研究了以铬黑T(EBT)作为其氢供体底物时的酶动力学行为。实验测定了Hb作为辣根过氧化物酶 (HRP)的替代物的类酶催化米氏常数和米氏速率。对Hb催化H2 O2 氧化铬黑T的机理作了探讨。建立了测定Hb的催化动力学光度法 ,方法的线性范围为 2× 10 - 8mol/L～ 2× 10 - 6mol/L ,检出限为 3.6× 10 - 9mol/L。用于血浆中游离Hb的测定 ,结果满意。     

血红蛋白与葡萄糖氧化酶偶联荧光法测定葡萄糖

利用血红蛋白(Hb)作为辣根过氧化物酶(HRP)的模拟酶,催化H2O2与对甲基酚的荧光反应.并将该反应与葡萄糖氧化酶(GOD)催化氧化葡萄糖的反应偶联,建立了测定葡萄糖的荧光分析法.方法的线性范围为0.0～5.0×10-5mol/L葡萄糖.检测限为6.5×10-8mol/L.用于测定人血清中葡萄糖的含量,获得了满意的结果.     

ODA-H_2O_2-HRP伏安酶联免疫分析新体系的研究

提出邻联茴香胺-H_2O_2-HRP伏安酶联免疫分析新体系,并用于测定HRP和HRP标记物.该方法是将HRP催化H_2O_2氧化邻联茴香胺的酶催化反应与邻联茴香胺的氧化产物的电极还原反应相偶合,在BR缓冲溶液中,在-0.56V(SCE)左右产生灵敏的极谱波.应用此极谱波测定HRP的检测限为3.7×10~(-12)g/mL,线性范围为1.O×1O~(-11)～2.0×10~(-9)g/mL.对邻联茴香胺-H_2O_2-HRP伏安酶联免疫分析新体系的偶合反应机理及电极还原过程进行了较详细的探讨.     

OT-H2O2-HRP伏安酶联免疫分析新体系

本文首次提出了邻联甲苯胺(OT)-H2O2-辣根过氧化物酶(HRP)伏安酶联免疫分析新体系。本方法以线性扫描二阶导数伏安法检测HRP催化H2O2氧化OT的产物, 用于游离HRP和各种HRP标记物测定, 灵敏度比经典的ELISA光度法分别高两个至四个数量级。测定游离HRP的检测限达到1.8×10^-^1^2 g/mL, 线性范围为5.0×10^-^1^2-1.0×10^-^8 g/mL。对此伏安酶联免疫分析新体系的偶合反应机理及电极还原过程也进行了详细的研究。     

Cyanide Exchange between Isobutyl Methylphosphonocyanidate and Hydrogen Cyanide in the Presence of Amines

Russian Journal of General Chemistry -     

Microdetermination of Cyanide

Abstract

A volumetric procedure is described for the micro-determination of cyanide. Small amounts of cyanide can be estimated even in presence of chloride if it is present in the electrolytic bath. N-Bromosuccinimide (NBS) is used to quantitatively oxidized cyanide to cyanate. The end point is reached when the rose red color of the bordeaux red is changed to distinct yellow. From 1–6 mg. of cyanide were analyzed with an average relative standard deviation of about 0.66%.     

Cyanide und Halogene

Ohne Zusammenfassung     

A Sensitive Colorimetric Reagent for the Determination of Cyanide and Hydrogen Cyanide in Various Environmental Samples

A sensitive reagent system is proposed for the determination of cyanide and hydrogen cyanide in various environmental samples. The method is based on the conversion of cyanide into cyanogen bromide followed by its reaction with pyridine to form glutaconic aldehyde. The glutaconic aldehyde so formed is coupled with p‐aminoacetophenone forming yellow‐orange polymethine dye measured at 445 nm. The colour system obeys Beer's law in the range of 0.01–0.16 ppm of cyanide inaqeous phase and 0.002–0.03 ppm in extracting system. The molar absorptivity and Sandell's sensitivity were found to be 6.51 × 10⁵ l mol^?1 cm^?1 and 0.0001 μg cm^?2, respectively. The method has been successfully applied for the determination of cyanide in air, industrial effluent, biological samples, and in the pesticide acrylonitrile.     

Adsorption of Zinc and Cyanide from Cyanide Effluents on Anionic Ion-exchange Resin

The adsorption of zinc and cyanide from cyanide effluents onto strong and weak basic anion exchange resins was studied in a batch adsorption system. Factors influencing the adsorption rates such as resin selection, resin amounts, contact time and temperature were studied and scanning electron microscopy-energy disperse spectroscopy(SEM-EDS) was used in the analysis. The present study shows that the adsorption capacity of resin 201×7 is better than that of resin 301. The adsorption process was relatively fast and came to equilibrium after 60 min. The kinetic data were analyzed with three models and the pseudo-second-order kinetic model was found to agree with the experimental data well. The equilibrium data could also be described well by Langmuir isotherm model. Thermodynamic parameters such as enthalpy change(ΔH⁰), free energy change(ΔG⁰) and entropy change(ΔS⁰) were calculated and the adsorption process was spontaneous and endothermic.     

Einfache und komplexe Cyanide

Ohne Zusammenfassung     

Chemiluminescence Determination of Cyanide Ions

It was found that alkaline solutions of luminol exhibit chemiluminescence in the presence of p-nitrobenzaldehyde (p-NBA), hemin, and cyanide ions. Air oxygen dissolved in the solutions is an essential component of the process. The kinetics of luminol chemiluminescence in the presence of p-NBA, hemin, and cyanide ions indicates the catalytic nature of the process. A scheme was proposed for the series of reactions resulting in chemiluminescence and generated by superoxide radicals formed in the p-NBA-catalyzed reaction between hemin-activated air oxygen and hydrated p-NBA species. A procedure was developed with a determination limit of (1.0 ± 0.3) × 10^?7 mg/mL (n = 5, P = 0.95) for cyanide ions.