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101.
Giuseppe Palleschi Mohammad H. Faridnia Glenn J. Lubrano George G. Guilbault 《Analytica chimica acta》1991
Electrochemical biosensors for lactate were assembled and used for the determination of lactic acid in saliva. Saliva was collected from healthy subjects and immediately screened for its lactate content. The electrochemical and biological interferences from saliva were discriminated by using a dual platinum electrode and blocking membranes. The stability, reproducibility and lifetime of the probe were studied. Lactate was measured in eight subjects in fasting conditions and after eating, showing an increase in lactate for each subject after meals. Correlation with a spectrophotometric lactate measurement is reported. Subjects before, during and after physical exercise showed consistent variations of lactate in saliva. 相似文献
102.
聚邻苯二胺修饰电极抗坏血酸氧化酶生物传感器的研究 总被引:6,自引:0,他引:6
本文报道了聚邻苯二胺/抗坏血酸氧化酶生物传感器,用这种传感器测定人体血清中的抗坏血酸,线性范围在1.0×10^-4~2.5×10^-7mol/L之间,响应时间为7s,检测限为1.0×10^-8mol/L。该传感器具有选择性好、灵敏度高和响应时间短等特点。 相似文献
103.
104.
Abu Zeid Abd El Basat Hassanein 《合成通讯》2013,43(21):3883-3895
Synthesis of indenopyridine-2-thione derivatives 6a-e via reaction of compound 1 with thioamides 2a-e in good yields. Several thieno[2,3-b]indeno[2,1-e]pyridine 9a-e have been synthesized. Some of them was used as a key intermediate in synthesis of 10-12. On the other hand, compound 1 reacted with various reagents to yield 16, 19, 21-24. 相似文献
105.
Enantioselective biocatalysis in nonaqueous media is becoming increasingly important in preparative synthetic chemistry. This article discusses (1) the general catalytic properties of enzymes in nonaqueous environments, (2) the basic principles that govern lipase-catalyzed enantioselective esterification and transesterification reactions in organic media for the preparation of optically active acids and alcohols, (3) the determination of kinetic and thermodynamic parameters, and (4) the quantitative analysis of published data. 相似文献
106.
107.
Monoamine oxidase (MAO) enzymes regulate the level of neurotransmitters by catalyzing the oxidation of various amine neurotransmitters, such as serotonin, dopamine and norepinephrine. Therefore, they are the important targets for drugs used in the treatment of depression, Parkinson, Alzeimer and other neurodegenerative disorders. Elucidation of MAO-catalyzed amine oxidation will provide new insights into the design of more effective drugs. Various amine oxidation mechanisms have been proposed for MAO so far, such as single electron transfer mechanism, polar nucleophilic mechanism and hydride mechanism. Since amine oxidation reaction of MAO takes place between cofactor flavin and the amine substrate, we focus on the small model structures mimicking flavin and amine substrates so that three model structures were employed. Reactants, transition states and products of the polar nucleophilic (proton transfer), the water-assisted proton transfer and the hydride transfer mechanisms were fully optimized employing various semi-empirical, ab initio and new generation density functional theory (DFT) methods. Activation energy barriers related to these mechanisms revealed that hydride transfer mechanism is more feasible. 相似文献
108.
报道用催化反应热诱导激光光偏转法测定痕量尿素。发现将脲酶制成一定浓度的乙醇浓液能显著地增强激光光偏转信号强度。探讨了增强作用机理以及光偏转号强度与尿素浓度的关系,并应用于尿样中尿素含量的测定,结果满意。 相似文献
109.
110.
《Analytical letters》2012,45(18):1607-1624
Abstract An extremely specific creatinine electrode was successfully developed for selective analysis of aqueous creatinine with a linear response over the range from 5 mg/l to 100 mg/l. The endogenous and exogenous species generally present in the serum do not interfere in the assay with the exception of ammonia. With the use of the electrode serum samples containing high creatinine can be assayed directly after pre-treatment. However, the electrode is not sensitive enough to detect the normal level serum creatinine due to the dilution of the serum after treatment. 相似文献