Determination of Some Phenothiazine Drugs Based on Colour Reaction with Potassium Periodate

ABSTRACT

A simple, rapid and sensitive method for the determination of six phenothiazine drugs, either in pure form or in pharmaceutical formulations, is described. The method is based on the formation of stable phenothiazine free radical by the use of potassium periodate as the chromogenic reagent in sulphuric acid medium. The reaction is suggested to proceed via oxidation of the phenothiazine nucleus into a semiquinonoid radical. The wavelengths of maximum absorption range from 500 to 525nm. Molar absorptivities range from     

锌试剂和高碘酸钾反应动力学测定超痕量锰

在 p H4.74的 HAc- Na Ac缓冲溶液中 ,以氨三乙酸为活化剂 ,KIO4 氧化锌试剂的反应受 Mn( )的催化加速 ,从而建立了测定超痕量锰的新方法。研究了影响反应速率的条件 ,测定了反应的表观活化能及表观速率常数。该法的检出限为 2 .4× 1 0 -11g/m L,测定范围是 0 .0～ 2 0 ng/1 0 m L。可用于蒸馏水中超痕量锰及大豆、面粉中痕量锰的测定     

乙基罗丹明B和高碘酸钾反应动力学测定痕量铑

研究了一个动力学测定铑的方法。在氯化钠－磷酸溶液和加热下铑催化乙基罗丹有Ｂ褪色,１ｇ（Ａ０／Ａ）与铑浓度呈线性的范围是０．２－４．０μｇ／２５ｍＬ,检出限为２．２４×１０＾－１０ｇ／ｍＬ,对２．０μｇ铑标准溶液测定１１次的相对标准偏差为２．１３％。     

丁基罗丹明B-高碘酸钾动力学光度法测定铑

报道了以铐催化高碘酸钾氧化丁基罗丹明B为基础的动力学测定痕量铑的方法,详细研究了动力学条件,建立了动力学光度测定痕量铑的新方法,铑浓度在0～180μg/L范围内与log(A_o/A)呈线性关系,检出限为2.84×10~(-7)g/L,该反应对Rh(Ⅲ)或丁基罗丹明B为一级反应,表观活化能为64.04kJ/mol.本方法用于某些催化剂中铑的测定,其相对标准偏差为1.76%～3.46%,回收率为96.8%～104.7%.     

SpectrophoStonetric Determination of IO4- by Fading Reaction of Chlorophosphonazo-pN with Potassium Periodate

2-(4-chloro-2-phosphonophenylazo)-7-(4-nitrophenylazo)-1,8-dihydroxy-3,6-napht-halenedisulfonic acid (Chlorophosphonazo-Pn) has been proposed as a sensitive color reagent for the determination of metal ions by spectrophotometry,1,2 but the determination of IO4-by fading reaction of chlorophospho nazo-Pn has not been reported.     

Determination of Catecholamines by Resonance Raman Spectroscopy of Their Aminochromes

Abstract

Catecholamines are oxidized by ferricyanide to the corresponding aminochromes. The band intensities of the resonance-enhanced Raman active C=N⁺ stretches of the aminochromes (1400–1500 cm^?1) are used to determine the catecholamines at the 10^?5 M level without prior separation.     

Catalymetric Determination of Rhodium Based on the Reaction of the Oxidation of Triphenylamine-4-Sulfonic Acid by Sodium Periodate

The catalytic activity of rhodium(III) was studied in the reaction of the oxidation of triphenylamine-4-sulfonic acid by sodium periodate at pH 3. The dependence of the reaction rate on the technique of catalyst preparation, the presence of activators, the concentrations of the components, and the acidity and temperature of solutions was revealed. A sensitive and selective method for the catalymetric determination of rhodium(III) is proposed and tested with synthetic mixtures.     

单宁协同高碘酸钾氧化亚甲基蓝褪色动力学光度法测定单宁

1 引言。单宁是一类广泛存在的多元酚类化合物,来源于某些植物(如茶、水果等)。单宁具有收敛性,可用于治疗胃肠道出血、溃疡和水泻等症;外用于创伤、灼伤,可减少分泌和防止感染,有局部止血作用;此外单宁还具有抗癌变、抗衰老、消炎、驱虫、降血压等医疗作用,成为近年来酚类物质的研究热点。因此,研究简单、快速,操作简便的单宁测定方法具有重要意义。目前测定单宁的方法有滴定法、蛋白质预沉淀法、高效液相色谱法和化学发光法等;实验观察到在碱性和室温条件下,高碘酸钾氧化亚甲基蓝的反应较慢;而加人少量的单宁后,高碘酸钾与单宁反应,产生单线态活性氧。单线态活性氧极为活泼,高碘酸钾和单线态活性氧共同作用于亚甲基蓝,从而加快了亚甲基蓝的氧化,单宁起了协同氧化的作用。据此建立了测定单宁的协同氧化动力学光度法,应用于巾药五倍子、诃子中单宁的测定,结果满意。     

Determination of Some Catecholamines by Coulometric Titration and Cyclic Voltammetry

Catecholamines quantitatively react with electrogenerated halogens. The reactions of adrenaline with bromine and iodine involve three electrons, and the reactions of dopamine with chlorine and bromine involve two electrons. Possible reaction schemes are proposed. Adrenaline and dopamine are reversibly oxidized at graphite and glassy-carbon electrodes in acid media at 0.7 and 0.58 V, respectively, to form corresponding quinones. Determination limits and linearity ranges of oxidation current were found as functions of catecholamine concentrations. The relative standard deviation was 1–4% for model solutions. A procedure was proposed for the electrochemical determination of adrenaline and dopamine in pharmaceuticals.__________Translated from Zhurnal Analiticheskoi Khimii, Vol. 60, No. 7, 2005, pp. 753–758.Original Russian Text Copyright © 2005 by Ziyatdinova, Budnikov.     

高碘酸钾氧化溴甲酚紫动力学光度法测定间苯二酚

在碱性和沸水浴条件下,微量的间苯二酚对高碘酸钾氧化溴甲酚紫褪色的反应具有显著的促进作用,据此建立了测定间苯二酚的新动力学光度法。该方法测定间苯二酚的线性范围为0．10～5．0μg／mL,检出限为0．041μg／mL,对于2．0μg／mL的间苯二酚11次测定的相对标准偏差是1．94％。方法用于皮炎宁酊及水样中间苯二酚的测定,结果满意。     

A Study on the Reaction of Periodate with Paracetamol and Its Application

Abstract

Periodate has been determined using fluorometric analysis of the fluorescent product when periodate and paracetamol were mixed in acidic medium. The calibration graph was linear between 4.8×10^?7–5.6×10^?6 mol/liter, and the detection limit is 4.0×10^?8 mol/liter. The proposed method was applied to the determination of the total content of different iodine forms in kelp samples, and the results were satisfactory.     

高碘酸盐氧化罗丹明B催化光度法测定钌

在０．７２ｍｏｌ／Ｌ磷酸和９０℃水浴条件下,钌催化高碘酸盐氧化罗丹明Ｂ（ＲＢ）,据此建立了高灵敏催化光度测定钌的方法。方法的检出限为８．０×１０＾－１２ｇ／ｍＬ,测定范围为０．２～１５ｎｇ／２５ｍＬ,对５、１０、１５ｎｇ／２５ｍＬＲｕ（Ⅲ）测定的相对标准偏差分别为８．６７％,５．９４％和１．８５％。本反应对Ｒｕ（Ⅲ）、ＲＢ、ＫＩＯ４和Ｈ３ＰＯ４均为一级反应,表观活化能为３６．０５ｋＪ／ｍｏｌ。１３     

甲基红-高碘酸钾催化光度法测定铱

在稀硫酸介质中 ,铱可催化高碘酸钾氧化甲基红褪色 ,据此建立了一个测定铱的催化光度新方法。铱的浓度在 0～ 2 .0μg/ 2 5 m L范围内与催化反应速率呈线性关系 ,检出限为 6.44× 1 0 - 4μg/ m L。对 0 .1 μg Ir( )及 1 .0 μg Ir( )独立测定 1 0次的相对标准偏差分别为 1 .98%和 1 .82 %。本法对冶金产品和岩矿中铱测定的相对标准偏差为 0 .64%～ 2 .30 %,标准加入回收率为 98.8%～ 1 0 3.8%。     

Simultaneous Determination of Fourteen Catecholamines and Their Metabolites by High Performance Liquid Chromatography with Electrochemical Detection

Abstract

A simple method has been developed for simultaneous determination of 14 catecholamines and their metabolites in cerebrospinal fluid and brain tissue by reversed-phase, ion-pair high-performance liquid chromatography with electrochemical detection. The time required for complete separation and analysis of all compounds was less than 35 min. Quantitation was based on the use of an internal standard isoproterenol. The mobile phase consisted of a 91:9 (v/v) mixture of 0.1 M formic acid and acetonitrile containing sodium-1-octane sulfonic acid. Using this method, analysis of neurotransmitters in brain tissue can be accomplished without a clean-up procedure.     

高碘酸盐氧化耐尔蓝动力学光度法测定锇

在硫酸介质和热水浴中 ,Os( )对高碘酸盐氧化耐尔蓝有催化作用。研究了反应速率对酸度、浓度、温度和离子强度的依赖关系 ,采用 0 .0 1 0mol/ L硫酸 ,反应的灵敏度随温度升高而增大 ,反应速率对反应混合物的离子强度依赖较小。线性范围为 0～ 0 .2 5μg/ 2 5m L;检出限为 8.0 2× 1 0 -5 μg/ m L;对质量浓度为 0 .1 0 μg/ 2 5m L 的 Os( )测定的相对标准偏差为 1 .0 2 % ( n=1 1 ) ;导出了催化反应的动力学方程 ;探讨了反应机理。4 0 0倍量以上常见金属离子不干扰锇的测定 ,1 0倍量以上的 Ru( )、Fe3 +有干扰。本法已用于贵金属冶金样品中锇的测定。     

高碘酸钾氧化荧光素动力荧光法测定痕量锰

本文报道了酸性介质,以氨三乙酸为活化剂,高碘酸钾氧化荧光素,动力荧光法测定痕量锰的新体系。方法检出限为7.3×10~(-2)ng/ml,线性范围为0.1～3.2ng/ml,常见离子基本上不干扰测定。用于直接测定水样中锰。     

过碘酸钾氧化鸡冠花红动力学光度法测定食品中痕量碘

基于硫酸介质中，草酸钠作活化剂，碘催化过碘酸钾氧化鸡冠花红而使其褪色的反应，建立了测定痕量碘的新方法。方法灵敏、简便、选择性好。测定碘的线性范围为０－２０μｇ／Ｌ；检出限为０．６６μｇ／Ｌ。用于食品中痕量碘的测定，结果满意。     

Flow-injection Chemiluminescence Determination of Catecholamines

Catecholaminesarenowwidelyusedinthetreatmentofbronchialasthma,hypertension,heartfailureassociatedwithorganicheartdiseases,andcardiacsurgery'.Thedeterminationofcatacholaminesinpharmaceuticalpreparationshasappearedespeciallyattractive.Chemiluminescence(CL)hasbeenexploitedinanumberofanalyticalapplicationsowingtoitsgreatsensitivity.SomeCLreactionshavenotfoundmanyapplicationsduetotheinstabilityofoxidationreagentssuchashypochlorite.WeproposedthatunstablereagentsrequiredforCLreactioncanbegenerated…     

高碘酸钾-鲁米诺后化学发光反应的研究——流动注射-后化学发光法测定异烟肼

实验发现了异烟肼在高碘酸钾-鲁米诺化学发光反应体系中的后化学发光反应。在对这一后化学发光反应的动力学性质、化学发光光谱、荧光光谱、紫外可见吸收光谱以及一些相关问题研究的基础上,讨论了其可能的反应机理;建立了利用此后化学发光反应测定异烟肼的流动注射化学发光新方法。方法的线性范围为1.0×10-9~4.0×10-7g/mL,检出限为6×10-10g/mL,对5.0×10-8g/mL的异烟肼进行11次平行测定的相对标准偏差为1.7%。此法已用于异烟肼片剂中异烟肼含量的测定,结果与药典法测定值一致。