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导数—同步荧光法同时测定尿液肾上腺素和去甲肾上腺素   总被引:2,自引:0,他引:2  
吴惠毅  陈晋 《分析化学》1997,25(4):496-496
1引言尿液肾上腺素(E)、去甲肾上腺素(NE)含量测定通常采用高效液相色谱、荧光分光光度法,前者虽然准确,但需要价格昂贵的仪器;后者由于E、NE氧化后产生的荧光光谱严重重叠,因而影响测定结果的准确性。本文将同步荧光扫描和导数光谱两种技术结合起来用于E、NE同时检测,获得了成功,建立一种简单、可靠、成本低廉、适合于常规开展的尿液E、NE测定方法。2实验部分2.1仪器与试剂HitachiF-4010型荧光分光光度讣(日本日立);石英亚沸蒸馏器。2mol/LpH8.6Tris-HCI缓冲液(含0.13…  相似文献   

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连串反应速差动力学分析中的数据处理方法的研究吴新国,蔡汝秀,林智信,程介克(武汉大学化学系,武汉,430072)关键词连串反应,速差动力学分析,比例方程法,肾上腺素,去甲肾上腺素动力学分析在分析化学中的作用和重要性已广为人知[1],速差动力学分析是其...  相似文献   

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胡深 《分析化学》1998,26(6):752-756
用自组装的毛细管电泳微电极安培检测系统,分析了鼠的单个交感神经细胞。大白鼠经麻醉、微解剖及酶解分离出新鲜的单个交感神经细胞。采用全细胞进样,用异丙肾上腺素 作内标。测定了儿茶酚胺类神经递质去甲肾上腺素和肾上腺素。检测限分别达 57 amol和 59 amol。八个活细胞分析结果,每个细胞平均含去甲肾上腺素 455 amol及肾上腺素 65 amol。  相似文献   

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利用紫外吸收光谱法结合计算机模拟研究了肾上腺素(Adin)在Cu(Ⅱ)离子催化下,用H2O2氧化产生肾上腺素红(Adorn)及其进一步反应的动力学。考察了有关反应的速率随Adin的初始浓度、Cu(Ⅱ)高子浓度和H2O2浓度的变化情况。并提出有关反应可能的机理,半定量地解释了相应的动力学行为。  相似文献   

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考察各种因素对β-环糊精及其衍生物分离肾上腺素类药物的影响.采用毛细管区带电泳法(CZE)对去甲肾上腺素、肾上腺素和异丙肾上腺素的手性分离进行研究.未涂渍熔融石英毛细管50 μm×58.5 cm(有效长度50 cm);温度20℃,操作电压30 kV,正极进样50 mbar×3 s,检测波长204 nm.β-环糊精(β-CD)及其两种衍生物作为手性选择剂.异丙肾上腺素得到了基线分离,肾上腺素和去甲肾上腺素未分离.  相似文献   

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本文基于肾上腺素、去甲肾上腺素和多巴胺对鲁米诺-铁氰化钾化学发光体系的增敏作用,建立了一种高效液相色谱分离-化学发光检测体系同时检测三种物质;研究了试剂浓度、酸碱条件、流动相成分等参数对分析结果的影响。在优化发光条件下,以邻苯二甲酸氢钾-甲醇溶液(92:8)为色谱流动相,用C18柱分离检测肾上腺素、去甲肾上腺素和多巴胺样品,肾上腺素线性范围为1×10-8~5×10-6g/mL,检测限4.0×10-9g/mL;去甲肾上腺素线性范围是 5.0×10-9~1.0×10-6g/mL,检测限1.0×10-9g/mL;多巴胺线性范围为5.0×10-9~1.0×10-6g/mL,检测限8.0×10-10g/mL。本方法快速、简便而准确,且已成功用于血清中三种物质的分析。  相似文献   

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孟昭仁  奚洪民 《分析化学》2001,29(3):371-371
1 引  言盐酸肾上腺素和重酒石酸去甲肾上腺素均为邻苯二酚的同系物 ,其药物制剂的含量测定文献报道为高氯酸非水滴定法和重量法 ,电分析方法目前还未见报道。本文根据盐酸肾上腺素和重酒石酸去甲肾上腺素因具邻苯二酚结构 ,极易氧化变色 ,可先失一个电子形成半苯醌游离基 ,后再失去一个电子为苯二醌 ,为一强氧化剂 ,在以Zn2 +作催化剂 ,K2 CrO4 可与其发生快速定量的氧化还原反应 ,且在 1 5mol/LNH4 Ac NH4 OH(pH 8.0 )底液中 ,K2 CrO4 可使汞膜 银电极的示波极谱图形呈现一敏锐切口 ,因此本文建立了以K2 C…  相似文献   

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本文推导了玻璃碳电极上可逆溶出催化过程的理论电流方程、峰电流及峰电势方程,得知溶出催化伏安法所得的峰电流比溶出伏安法的峰电流提高了数十倍,从而进一步提高了溶出伏安法的灵敏度。本文还用碲的溶出催化实验验证理论方程。所得实验结果均与理论方程相吻合。  相似文献   

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本文对在玻璃碳电极上不可逆溶出催化的理论进行了研究,推导了溶出催化过程的电流方程,峰电流和峰电势方程,并用微计算机模拟出各种关系曲线,从理论方程得知溶出催化伏安法所得的峰电流比溶出伏安法的峰电流提高了二个数量级。本文还用钯的溶出催化实验验证理论方程,所得的实验结果均与理论方程相吻合。  相似文献   

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We describe the method of achieving the first completely general simulation of ac linear sweep and cyclic voltammetry making use of the fully implicit Richtmyer modification (FIRM) method. The simulation technique is applied to a reversible process under conditions where a sinusoidal waveform of any amplitude is superimposed onto the dc potential which is swept at a finite scan rate. Results, where possible, are compared with the existing theory derived at constant dc potential to confirm the fidelity of the simulation. In particular, we demonstrate excellent agreement with the results of Engblom et al. [J. Electroanal. Chem. xxx (1999) xxx] for large amplitude ac voltammetry described in the companion paper immediately preceding this article. The use of conventional and Fourier transform methods of data analysis are compared to highlight the advantages of the use of the fast Fourier transform algorithm in ac voltammetry.  相似文献   

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An electroanalytical method for the determination of morpholine, a corrosion inhibitor, was developed at a cathodically pretreated boron-doped diamond electrode (BDDE). The voltammetric response of morpholine at the BDDE in 0.1?mol L?1 KCl (pH 10) shows an irreversible oxidation process at approximately 1.3?V vs. Ag/AgCl in 3.0?mol L?1 KCl. Using cyclic voltammetry, the number of electrons involved in the morpholine electroxidation mechanism was found to be 1. The application of chronoamperometry showed that the apparent diffusion coefficient (D0) was 2.99?×?10?6 cm2 s?1. Using square wave voltammetry under the optimized conditions (frequency of 30.0?Hz, pulse amplitude of 100?mV and step potential of 20?mV at pH 10.0), the developed method provided limits of detection and quantification of 2.1 and 6.9?mg L?1, respectively, with a linear range from 5.0 to 100.0?mg L?1 (r?=?0.991). Intraday (n?=?10) and interday (two consecutive day) precision values assessed as the relative standard deviation for solutions containing 30.0, 60.0, and 90.0?mg L?1 of morpholine were from 0.41 to 5.86% and 0.92 to 3.19%, respectively. The feasibility of the method for the interference-free determination of morpholine was verified by the analysis of synthetic boiler water samples containing CaCO3, Na2SO3, Na3PO4, FeCl3, and humic acid as organic matter. In addition, hydrazine was added as a possible interfering compound because of its widespread use in corrosion inhibition. Recovery values from 90.9 to 109.4% were obtained in the synthetic boiler water, thereby attesting to the accuracy of the method.  相似文献   

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莫金垣  张润建 《分析化学》1995,23(3):255-258
本文提出平行催化体系的对位叠式循环方波伏安法,并对共作了系统的研究,推导了这一方法的催化电流理论方程,并用验验证这理论的正确性,得到其各脉冲电流皆为同方向,对位叠式循环催化电流相当于将电流叠加4次,而波形不受方波幅度大小的影响,因而灵敏度和分辨率有较大提高,优于其它方波伏安法。  相似文献   

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《Electroanalysis》2017,29(11):2672-2677
We report the design of an electrochemical sensor capable of detecting levofloxacin (LEVX) in complex biological samples. This detection strategy is simple, fast, and does not require sample pretreatment or electrode modification. Unlike previously developed electrochemical LEVX sensors that require direct oxidation of LEVX, the sensing mechanism is based on the complexation reactions between LEVX and iron(III), resulting in a concentration‐dependent decrease in the iron(III) reduction peak current and a shift in the peak potential. These changes are presumably attributed to the decrease in the concentration of uncomplexed Fe(III) in the solution. The concentration‐dependent change in both the current and potential can be used for quantification of LEVX in various samples, including 50 % synthetic urine and 25 % synthetic human saliva. The limit of detection was estimated to be in the range of 1.5 to 2.3 μM, concentrations that are much lower than the concentration of LEVX found in urine and saliva samples of patients administered this drug for conditions such as urinary tract infection. With further optimization, this sensing strategy could find applications in clinical pharmacokinetic studies.  相似文献   

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采用线性扫描伏安法和循环伏安法研究司帕沙星的电化学行为。在0.05 mol·L~(-1)硫酸溶液中,司帕沙星于-1.29 V(vs.Ag/AgCl)处产生一灵敏的还原峰,司帕沙星的浓度在1.0×10~(-6)~1.5×10~(-4)mol·L~(-1)范围内与其峰电流呈线性关系,检出限(3S/N)为2.0×10~(-7)mol·L~(-1)。该法用于司帕沙星片剂的分析,回收率为96.2%~105.0%,相对标准偏差(n=6)为2.4%。试验证实:司帕沙星在电极上产生的峰为具有吸附性的完全不可逆的还原峰。  相似文献   

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An applicable square wave anodic adsorptive stripping voltammetric (SWAdASV) technique was utilized for linagliptin determination. A glassy carbon electrode was modified with graphene oxide to increase the electrode reactivity. The method is cheap, accurate, precise, and selective, with a good linearity range and a low detection limit. The proposed method was the first one to determine linagliptin in the feces, which is the main route for excreting the drug from the body. The electrode was characterized using various techniques, including Scanning Electron Microscope (SEM), Fourier-transform infrared (FTIR), and X-ray powder diffraction (XRD), and the oxidation mechanism of the drug was examined. The proposed method has a linear range of 9.45–103.96 ng mL?1. The detection limit was 4.0 ng mL?1. The modified electrode was employed efficiently to determine the drug in tablet formulations, spiked human urine, plasma, and rats' feces with high recoveries. The proposed method's results were statistically compared with those of another previously published method.  相似文献   

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本文研究了微盘电极上单扫描、一次导教、二次导数及三次导数的稳态扩散电流方程,一次导数的电流峰与扫描速率v成正比,二次导数及三次导数的电流峰分别与v2、v3成正比,从而提高了响应灵敏度,通过它们的波形可以很方便地求得电极反应的标准电极电位,判断反应的可逆性,用碳纤维微盘电极进行了验证,结果与理论方程一致。  相似文献   

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用微分脉冲阴极吸附溶出伏安法测定了利多卡因针剂的含量。浓度与波高的线性范围为1×10~(-7)~3×10~(-4)mol/dm~3。最低检测限l×10~(-8)mol/dm~3。回收率98.07±0.05%。  相似文献   

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