共查询到20条相似文献,搜索用时 218 毫秒
1.
以邻氨基酚为底物的伏安酶联免疫分析体系酶促反应的研究 总被引:9,自引:0,他引:9
辣根过氧化物酶 (HRP)催化H2 O2 氧化邻氨基酚的酶促反应与邻氨基酚的氧化产物的电极还原反应相偶合的伏安酶联免疫分析新体系具有很高的灵敏度 ,测定HRP的检出限为 6 .0× 1 0 -10 g/L ,线性范围为 1 .0× 1 0 -9~ 4.0× 1 0 -6g/L .制备出了HRP催化H2 O2 氧化邻氨基酚的产物纯品 ,并应用电化学分析、高效液相色谱、紫外 可见光谱、红外光谱、13 C核磁共振谱、1H核磁共振谱、质谱、元素分析等技术对体系酶促反应进行了深入的研究 .在所选择的酶促反应条件下 ,生成的产物为 3 氨基吩嗪 .提出了酶促反应及其产物的电极还原过程 . 相似文献
2.
邻氨基酚-过氧化氢-辣根过氧化物酶伏安酶联免疫分析法测定人血清甲胎蛋白 总被引:2,自引:0,他引:2
提出了邻氨基酚(OAP)-H2O2-辣根过氧化物酶(HRP)伏安酶联免疫分析法测定人血清甲胎蛋白(α-FP)的新方法.该方法是将HRP催化H2O2氧化邻氨基酸的酶催化反应与邻氨基酚的氧化产物在滴汞电极上的还原反应相偶合,在BR缓冲溶液中,在-0.43 V(vs.SCE)左右产生灵敏的极谱波.根据测定标记在甲胎蛋白抗体上的HRP的量,求得发生免疫反应的 α-FP的含量。该方法对甲胎蛋白测定的线性范围为 1. 25~400 mg/L。用所建立的方法对病人血清样品进行了测定,并与酶联免疫吸附测定光度法(ELISA)进行对照,二者相关性很好。 相似文献
3.
4.
聚吡咯葡萄糖氧化酶电极的生物电化学响应 总被引:2,自引:0,他引:2
采用分步骤合过程,制备了以聚吡咯膜为载体的葡萄糖氧化酶电极,探讨了其生物电化学响应特性,计算了酶催化反应的有关动力学参数。与溶解态酶相比,该电极表现出良好的生物电化学特征,而且酶蛋白对溶液温度的稳定性有显著提高。 相似文献
5.
邻苯二胺、邻氨基酚的电化学聚合及聚合的膜性质 总被引:6,自引:0,他引:6
邻苯二胺(ODB), 邻氨基酚(OAP)在酸性水溶液中易电聚合, 可形成致密的聚合膜。聚邻苯二胺(PODB)在PH<4时具有电活性, 其氧化还原反应与电变色效应对应。聚邻苯二胺,聚邻氨基酚(POAP)膜电极电位在pH=4~10范围对pH有Nernst响应, 电极系数分别为59mV/pH和57mV/pH。响应时间小于3分钟。PODB, POAP膜能与Ni~(2+), Co~(2+)过渡金属离子形成稳定的聚合络合膜。此膜在碱性介质中具有稳定的循环伏安行为, 膜中的金属离子可被H~+交换。PODB电极的—NH_2基可再修饰引入醌/氢醌功能团。 相似文献
6.
7.
8.
米托蒽醌分子印迹聚邻氨基酚敏感膜传感器的研制 总被引:2,自引:0,他引:2
在弱酸性条件下,在金电极上以邻氨基酚为单体和交联剂,米托蒽醌为模板分子,用循环伏安法电聚合成米托蒽醌分子印迹聚邻氨基酚敏感膜传感器。该传感器对米托蒽醌具有良好的选择性和敏感度,米托蒽醌浓度分别在2.0×10^-7—1.0×10^-5mol/L及1.0×10^-5—5.0×10^-5mol/L范围内与峰电流减小量呈线性关系,检出限为1.2×10^-7mol/L。本文同时对分子印迹膜的结构和性能进行了探讨与研究。 相似文献
9.
10.
本文提出邻氨基酚 (OAP)-H2O2-辣根过氧化物酶(HRP)伏安酶联免疫分析体系并用于人血清中甲胎蛋白(αFP)的测定。该方法是将HRP催化H2O 2 氧化 OAP 的酶催化反应与邻氨基酚的氧化中间产物(邻苯醌亚胺)在滴汞电极上的还原反应相偶合, 在BR缓冲溶液中, 在-0.87 V (vs.SCE) 左右产生灵敏的极谱波。根据测定标记在甲胎蛋白抗体上的HRP的量, 求得发生免疫反应的αFP的含量。该方法对甲胎蛋白测定的线性范围为1.25~400 mg/L。用所建立的方法对病人血清样品进行了测定, 并与酶联免疫吸附测定光度法(ELISA)进行对照,二者相关性很好。 相似文献
11.
A bead based sandwich enzyme immunoassay coupled to electrochemical detection for ovalbumin has been developed. The enzyme label alkaline phosphatase was used to convert the substrate 4-aminophenyl phosphate to electroactive product 4-aminophenol. The detection was done in a microdrop by continuously monitoring the enzyme turnover with a rotating disk electrode. This reduces dilution of the enzyme product, a key to achieving low detection limits. The assay developed has a detection limit of 0.1 ng ml-1. Assay sensitivity in complex matrices such as food and serum was compared. 相似文献
12.
V. A. Safronova J. V. Samsonova V. G. Grigorenko A. P. Osipov 《Moscow University Chemistry Bulletin》2012,67(5):241-248
A new express method based on lateral flow immunoassay (LFIA) for progesterone detection was developed. To increase the assay sensitivity an enzyme label (horse-radish peroxidase) was used instead of colloidal gold. An optimal assay format was chosen and the influence of a range of buffer supplements (detergents, proteins and sucrose) was investigated by enzyme-linked immunosorbent assay (ELISA). Linear range of LFIA was between 2 and 40 ng/mL in buffer. Limit of detection was 2 ng/mL, assay time was within 15 min. 相似文献
13.
The principles of biocatalytic and bioaffinity biosensors are reviewed with emphasis on electron transfer-type enzyme sensors, optical enzyme sensors and optical immunosensors for homogeneous immunoassay. An enzyme sensor for ethanol was fabricated by electrochemical polymerization of pyrrole onto the surface of platinized platinum-adsorbed alcohol dehydrogenase—NAD—Meldola Blue. Ethanol was determined amperometrically by measuring the oxidative current through polypyrrole. An optical enzyme sensor is exemplified by an acethylcholine sensor based on an optical pH fibre sensor using a thin polyaniline film. The optical immunosensor for homogeneous immunoassay consists of an optical fibre, the end of the which is coated with an optically transparent platinum electrode. With using luminol as a label, highly sensitive homogeneous immunoassay is carried out by measuring the electrochemical luminescence of the label. 相似文献
14.
Frank F. Bier Eva Ehrentreich-Förster Christian G. Bauer Frieder W. Scheller 《Analytical and bioanalytical chemistry》1996,354(7-8):861-865
The amplification cycle consisting of NADH independent oligosaccharide dehydrogenase (ODH) and laccase has been recently reported to be highly sensitive to several catecholamines and p-aminophenol. A competitive immunoassay for 2,4-dichlorophenoxyacetic acid has been developed by combining this amplification cycle with β-galactosidase as enzyme label resulting in p-aminophenol as product. The combination of enzymatic amplification cycles with a competitive immunoassay yields a highly sensitive measurement of 2,4-dichlorophenoxyacetic acid. Using a monoclonal antibody the linear range of the assay was between 0.02 and 100 ng/l and the c50 was found at 0.2 ng/l; the detection limit was at 5 pg/l (25 fmol/l) corresponding to 5 amol. 相似文献
15.
E. I. Rainina I. E. Badalian O. V. Ignatov A. Yu. Fedorov A. L. Simonian S. D. Varfolomeyev 《Applied biochemistry and biotechnology》1996,56(2):117-127
A microbial sensor for concentration measurement of phenol in aqueous solutions has been developed. Phenol-utilizing cellsPseudomonas putida GFS-8 immobilized in poly(vinyl)alcohol cryogel were used as a biological transducer. Relationships between phenol concentration
in the activating medium and endogenic cell respiration have been established. Cell respiration and phenol concentration in
the assay solution positively correlated at a phenol concentration range of 0.1–2.0 mg/L and were linearly dependent in the
range of 0.1–1.0 mg/L. A Clark membrane electrode was the physiochemical transducer. The assay may be completed within 5 min.
The cells oxidize phenol, pyrocatechol, mesityl oxide, aniline, and do not react with a number of xenobiotics, sugars, and
alcohol. With the exception of aniline, most components found in waste waters from phenol production affect neither the assay
process nor the ability of these cells to use phenol as exogenic respiratory substrate. The immobilized cells retained their
ability to utilize phenol as an exogenic respiratory substrate for up to 1 mo. 相似文献
16.
We have developed a competitive enzyme immunoassay for a drug, which was a newly synthesized anti-ulcer agent, using an enzyme immunoassay. The polyclonal anti-drug antibody coupled to biotin, peroxidase labeled drug derivatives as a tracer, and a small column of Sepharose 4B covalently bound to avidin were used in the assay. This assay is simple and rapid, and the sensitivity and the measuring range can be controlled by the flow rate of the substrate solution. The correlation between serum drug concentrations (0.1-10 micrograms/ml) measured by gas chromatography and this assay was good (r = 0.991). This principle for the assay is very practical and applicable to the enzyme immunoassay for small and large molecules. 相似文献
17.
High sensitive competitive immunodetection of 2,4-dichlorophenoxyacetic acid using enzymatic amplification with electrochemical detection 总被引:1,自引:0,他引:1
Frank F. Bier Eva Ehrentreich-Förster Christian G. Bauer Frieder W. Scheller 《Fresenius' Journal of Analytical Chemistry》1996,354(7-8):861-865
The amplification cycle consisting of NADH independent oligosaccharide dehydrogenase (ODH) and laccase has been recently reported to be highly sensitive to several catecholamines and p-aminophenol. A competitive immunoassay for 2,4-dichlorophenoxyacetic acid has been developed by combining this amplification cycle with -galactosidase as enzyme label resulting in p-aminophenol as product. The combination of enzymatic amplification cycles with a competitive immunoassay yields a highly sensitive measurement of 2,4-dichlorophenoxyacetic acid. Using a monoclonal antibody the linear range of the assay was between 0.02 and 100 ng/l and the c50 was found at 0.2 ng/l; the detection limit was at 5 pg/l (25 fmol/l) corresponding to 5 amol. 相似文献
18.
An amperometric immunoassay was developed by coupling the enzyme-linked immunosorbent assay (ELISA) microtiter-plate system with a polyaniline-perfluorosulfonated ionomer composite (PA/NF) electrode incorporated flow injection analysis (FIA) system and used for the analysis of Tal 1 protein, found in leukemic T cell. Rabbit polyclonal antibody (pAb) against Tal 1 and urease-pAb were used, respectively as the captured protein and enzyme labeled conjugate for sandwich immunoassay of Tal 1. Characteristics of the PA/NF electrode such as reproducibility, stability and sensitivity were studied. The detection limits of the PA/NF electrode for NH4+ and urease were found to be 5 μM and 0.05 nM, respectively. Assay conditions such as the amount of pAb needed for coating the plate, the concentration of urease-pAb conjugate appropriate for the immunoreaction and the incubation time for urea to react with the bound urease-pAb in the microtiter-wells were also studied. A detection limit as lower as 0.5 ng/ml and a dynamic range of 1.0-100 ng/ml were found for the immunoassay of Tal 1 protein with the developed immunoassay system. 相似文献
19.
A sensitive and specific immunoassay method for detecting α-fetoprotein (AFP) based on electrogenerated chemiluminescence (ECL) was described. ECL could perform detection for a series of different concentrations of AFP. CdSe quantum dots (QDs) were used as labels and were linked to AFP antibody (anti-AFP, the secondary antibody, Ab2*). Immunoassay was carried out on a modified electrode using a sandwich assay approach, where anti-AFP (Ab1) was covalently bound to the surface of an Au electrode to be allowed to capture AFP specifically. Afterwards, Ab2* was allowed to bind selectively to the captured AFP. The non-specific adsorption was negligible. In the presence of H(2)O(2), the ECL intensity increased with the increase of AFP, which indicated that an immunosensor for AFP was constructed. The detection of AFP based on measuring the ECL intensity of CdSe without the enzyme and mediator can promote the stability of the immunosensor. The linear range of the AFP assay was from 0.002 to 32 ng mL(-1). Furthermore, the immunosensor showed high sensitivity, good precision, stability, and reproducibility and could be used for the detection of real samples with consistent results in comparison with those obtained by the enzyme-linked immunosorbent assay (ELISA) method. The strategy was successfully demonstrated as a simple, cost-effective, specific, and potential method to detect AFP in practical samples. 相似文献
20.
A new electrochemical immunoassay strategy was proposed based on electrostatic interaction of natural polymers. The chitosan-entrapped carbon paste electrode (CCPE) was used as the base electrode, alginates as carriers for the reactants and horseradish peroxidase (HRP) as enzyme label in the immunoassay. The immunoassay was firstly carried out using the homogeneous competitive immune format and a very high rate of immune reaction was reached since both reacting antibodies and antigens were in a solution phase. Subsequently quick heterogeneous separation of immune complexes attached to the alginates molecule from the solution phase was realized by making use of the strongly electrostatic attraction between the protonated amino groups of chitosans on the surface of CCPE and carboxylic groups of alginates. After washing the surface of CCPE, amperometric detection with hydroquinone and hydrogen peroxide as enzymatic substrates was carried out. A new surface of CCPE for repeated use in another assay can be obtained by polishing the original used one. The feasibility of the above approach was demonstrated using transferrin and transferrin-antibody as a model system. The dynamic concentration range for transferrin assay was 1.9 to 78.8 μg ml−1. 相似文献