银微盘电极上碘离子的示差脉冲溶出伏安法

基于Ｉ能与Ａｇ生成难溶出化合物特性，在银微盘电极上研究了Ｉ的示差脉冲溶出伏安法（ＤＰＳＶ）。该法不需镀汞，不要搅拌，可在较稀稀的支持电解质溶液中实施。于０．０８ｍｏｌ／ＬＨＡｃ－ＮａＣ及０．０１ｍｏｌ／ＬＥＤＴＡ介质中，能检出１．００×１０＾－８ｍｏｌ／Ｌ的Ｉ，Ｉ的浓度为５．００×１０＾－６－－１．２０×１０＾－８ｍｏｌ／Ｌ范围与峰电流有良好的线性关系。该法用于自来水中Ｉ的测定，相对偏差为４．３％     

头孢噻肟钠的降解及其产物伏安行为的研究

头孢噻肟钠在ＮａＯＨ溶液中降解后，于０．１ｍｏｌ／ＬＮａＯＨ中得一灵敏的吸附伏安原峰，Ｅｐ＝－０．７８Ｖ（νｓＡｇ／ＡｇＣｌ），ｉｐ与头孢噻肟钠浓度在１．０×１０＾－＾９－１．０×１０＾－＾８，１．０×１０＾－＾８－１．０×１０＾－＾７，１．０×１０＾－＾７－１．０×１０＾－＾６ｍｏｌ／Ｌ范围内呈线性关系，检出限为５．０×１０＾－＾１＾０ｍｏｌ／Ｌ。用多种电化学手段研究其降解产物的伏安行为，测定了     

银微盘电极上谷胱甘肽降解产物的伏安行为

谷胱甘肽是一个含硫三肽 ,基于谷胱甘肽降解产物中的L_半胱氨酸 (RS- )能与Ag+形成难溶化合物的性质 ,在银微盘电极上研究了其水解产物的伏安行为 ;运用示差脉冲溶出伏安法 (DPSV) ,在0.1mol/LHAc -NaAc介质中 ,谷胱甘肽降解产物的还原峰电流与谷胱甘肽浓度于9.0×10-7～4.0×10-5 mol/L范围内有较好的线性关系 ,测定限为5.0×10 -8mol/L ,用于模拟样品测定 ,结果令人满意     

半微分阴极溶出伏安法研究硫离子在银电极上的电化学行为

用半微分阴极溶出伏安法研究硫离子在银电极上的电化学行为。在ＮａＯＨ－ＥＤＴＡ－Ｎａ２ＳＯ３底液中，可消除溶解氧及部分重金属离子Ｃｕ２＋，Ｐｂ２＋，Ｚｎ２＋，Ｃｄ２＋和Ｎｉ２＋的干扰。一些阴离子Ｃｌ－，Ｉ－，ＮＯ－３和ＳＯ２－４不干扰。硫离子浓度在３．１９×１０－６ｍｏｌ／Ｌ至３．１３×１０－５ｍｏｌ／Ｌ范围内与溶出峰高成线性关系。对两种人发样品中硫含量测定的回收率分别为９３．９％和９７．８％。     

微分脉冲阴极溶出伏安法测定阿米卡星

硫酸阿米卡星(Am ikacin sulfate)是一种氨基糖苷酸类抗生素,化学名为O-3氨基-3-脱氧-а-D-蒲吡喃糖基-(1-6)-O-[6-氨基-6-脱氧-а-D-蒲吡喃糖基-(1-4)]-N-(4-氨基-2-羟基-1-氧丁基)-2-脱氧?D-链霉胺硫酸盐。目前报道的测定方法主要有高效液相法[1]、镍毛细管电泳法[2]。本文研究了阿米卡星在玻碳电极上的电化学行为。微分脉冲溶出伏安法是一种灵敏度很高的痕量分析方法,本文利用该方法对阿米卡星进行了测定,发现阿米卡星在pH=2的盐酸底液中,产生一灵敏的还原峰,可用于定量测定。平行测定了7次,RSD为2·05%,该方法可用于注射液及血清中…     

氨青霉素降解产物在汞膜电极上的伏安法研究

考察了氨苄青霉素在酸、碱条件下的降解产物于玻碳汞膜电极上的伏安行为,降解产物在醋酸缓冲溶液（pH5.5)的底液中均产生了灵敏的阴极还原峰,以碱降解条件为好。已将方法应用于模拟样品的分析。     

银微盘电极上头孢氨苄降解产物的伏安行为及其应用

基于头孢氨苄降解产物中含有巯基，能与Ａｇ＾＋生成难溶化合物的特性，在银微盘电极上研究了ＣＥＸ降解产物的伏安行为，探讨了电极反应的机理。运用示差脉冲溶出伏安法，在０．１ｍｏｌ／Ｌ ＨＡｃ－ＮａＡｃ介质中，ＣＥＸ降解产物的还原峰电流与ＣＥＸ浓度于８．０×１０＾－８－７．０×１０＾－６ｍｏｌ／Ｌ范围内呈良好线性关系；检测限为１．０×１０＾０８ｍｏｌ／Ｌ；测定了头孢氨苄胶囊中ＣＥＸ含量为９２．０％，与药典     

头孢唑啉降解产物在银亚微盘电极上的电化学行为及其测定

基于头孢唑啉在 ０．１０ｍｏｌ／Ｌ ＮａＯＨ溶液中水浴降解产物中含有巯基（－ＳＨ），在 ｐＨ ５．０ＮａＡｃ－ＨＡｃ介质中，于银亚微盘电极上产生一灵敏的吸附伏安氧化还原峰，其峰电位分别为 Ｅｐａ＝－０．５３０Ｖ和 ＥＰｃ＝－０．４００Ｖ。动力学研究表明：电极反应的电子转移数为０．９１，表观电子传递速率为ｋｓ＝０．１０ｓ－１，峰电流与头孢唑啉浓度在１．０×１０－６～５０×１０－１ｍｏｌ／Ｌ范围内呈良好的线性关系。方法可应用于人工合成样品头孢啉的检测。     

Electrochemical Behavior of 6-Mercapto-Purine at Hanging Copper Amalgam Dropping Electrode and Its Trace Determination by Differential Pulse Adsorption Cathodic Stripping Voltammetry

Abstract

The electrochemical behavior of 6-MP was studied by cyclic voltammetry at a hanging copper amalgam dropping electrode (HCADE). It was found that 6-MP could form a complex with the Cu(II) stripped from the HCADE, showing a new peak at ?0.19V in the medium of 0.1mol/L LiClO₄-0.5mol/L HClO₄ solution. The mechanism of the reaction was proposed. This new peak was sensitive and could be used for the determination of trace 6-MP by differential pulse adsorption cathodic stripping voltammetry (DPAdCSV). The linear range was from 3.6×10^?10 to 5.3×10^?6 mol/L, and the detection limit was about 1.2×10^?10 mol/L (S/N=3). The method was also successfully applied to the determination of 6-MP in pharmaceutical tablets.     

Coprecipitative Preconcentration and Differential Pulse Cathodic Stripping Voltammetric Determination of Selenium (IV)

Abstract

A DPCSV procedure for the determination of selenium (IV) with a prior preconcentrative coprecipitation on iron (III) hydroxide has been developed. The experimental conditions for coprecipitation of selenium (IV) onto iron (III) hydroxide, viz. pH, iron (III) concentration, volume of aqueous phase and selenium concentration, were optimized. The coprecipitated selenium (IV) is dissolved in 10 ml of 0.1 M HCl and analysed using DPCSV in the presence of copper (II). Selenium concentrations as low as 10–100 ng present in 500 ml of the aqueous phase could be determined. The method is precise and has been applied to the analysis of sea water and reference material samples.     

Cathodic Stripping Voltammetry Of Cerium

Abstract

The experimental conditions for the accumulation of cerium as insoluble Ce₃(PO₄)₄ on a platinum indicator electrode were studied. The determination of cerium down to 0.01% in oxides of other lanthanides is described.     

微分脉冲阴极吸附溶出伏安法测定利多卡因

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%。     

Nafion修饰电极阴极溶出伏安法测定痕量钛

本文采用Ｎａｆｉｏｎ修饰玻碳电极阴极溶出伏安法测定痕量钛。研究了Ｎａｆｉｏｎ膜的有关特性和测定的佳化条件。当富集时间为１ｍｉｎ时，Ｔｉ（Ⅳ）浓度与峰电流在１．０～５０ｎｇ／ｍｌ范围内呈线性关系。本法应用于铝合金和白泥标样中钛的测定，结果满意。