离子色谱中的安培检测方法及其应用

介绍了离子色谱中的安培检测方法(包括恒电位安培检测法、脉冲安培检测法和积分脉冲安培检测法)的原理和应用。脉冲安培检测法与高效阴离子交换色谱结合(HPAEC-PAD)是一种新的分析糖类化合物的方法;积分脉冲安培检测法与高效阴离子交换色谱结合(HPAEC-IPAD)是一种新的氨基酸分析方法。     

高效液相色谱-脉冲安培检测法测定脑微透析溶液中单胺类神经递质

详细对比了脉冲安培与恒电位安培检测单胺类神经递质的响应值,结果表明冲安培检测上述物质的响应值是恒电位安培检测的1.2倍。建立了以3.4 -二羟基苄胺（DHBA）为内标的定量方法。在微透析溶液中的微量神经递质的回收率在74％－101％之间。     

几种样品中溴与碘的离子色谱安培法测定

1 引言 许多样品通常要求测定溴和碘的含量,往往含量甚微,电导检测的离子色谱法达不到要求。本文研究了离子色谱安培法连续测定溴和碘的可行性,拟定了一个快速、简便,无干扰的、可同时测定各种样品中痕量溴和碘的方法。本法以艾斯卡半熔,抗坏血酸为还原剂,使样品中的碘全部转变成适合于离子色谱安培法检测     

高效阴离子交换色谱-脉冲电化学检测方法和应用

评述了高效阴离子交换色谱和脉冲电化学检测方法。内容包括：色谱柱和流动相;糖和氨基酸在色谱柱上的保留行为;脉冲安培法(PAD)和积分脉冲安培法(IPAD);方法在糖和氨基酸分析中的应用。     

糖的高效阴离子交换色谱-脉冲安培检测法分析

高效阴离子交换色谱-脉冲安培检测法是新近发展的一种分析糖的有效方法。本文讨论了糖的高效阴离子交换色谱分离和脉冲安培法检测的原理,色谱条件的选择,包括分离糖的固定相、流动相以及检测糖的脉冲电位波形,并对方法的应用进行了较为详细的叙述。     

高效液相色谱-喷壁/薄层安培检测器用于同时测定5种环境优先污染酚

结合传统的喷壁式和薄层式安培检测器,制备了一种新型的喷壁/薄层安培检测器。联合高效液相色谱(HPLC)同时对5种环境优先污染酚进行了检测。实验发现,安培检测工作电极面积的增大会导致响应电流的增大,但同时也会增大噪声,因此,基于信噪比优化电极面积是重要的。选用色谱柱SHIM-PACK VP-ODS(150 mm×4.6 mm),流动相V(甲醇)∶V(0.1 mol/L PBS,pH=7.5)=40∶60,柱温40℃,流速1 mL/min,进样量20μL,安培检测电位为1.0 V,紫外检测波长为220 nm,喷壁-薄层安培检测器不经富集对对硝基酚、苯酚、间甲酚、2,4-二氯苯酚和2,4,6-三氯苯酚共5种酚类物质的检测下限均低于1μg/L(S/N=3),优于相同条件下的紫外检测器和商品电化学检测器。用于实际水样分析亦获满意结果。     

高效液相色谱-喷壁/薄层安培检测器用于同时测定5种环境优先污染酚

结合传统的喷壁式和薄层式安培检测器,制备了一种新型的喷壁/薄层安培检测器。 联合高效液相色谱（HPLC）同时对5种环境优先污染酚进行了检测。 实验发现,安培检测工作电极面积的增大会导致响应电流的增大,但同时也会增大噪声,因此,基于信噪比优化电极面积是重要的。 选用色谱柱SHIM-PACK VP-ODS（150 mm×4.6 mm）,流动相V（甲醇）∶V（0.1 mol/L PBS,pH=7.5）=40∶60,柱温40 ℃,流速1 mL/min,进样量20 μL,安培检测电位为1.0 V,紫外检测波长为220 nm,喷壁-薄层安培检测器不经富集对对硝基酚、苯酚、间甲酚、2,4-二氯苯酚和2,4,6-三氯苯酚共5种酚类物质的检测下限均低于1 μg/L(S/N=3),优于相同条件下的紫外检测器和商品电化学检测器。 用于实际水样分析亦获满意结果。     

局部麻醉药的反相色谱安培法检测

本文系统研究了普鲁卡因,利多卡因,丁卡因等3种局部麻醉药的液相色谱安培法检测行法,并与液相色谱光度法检测结果进行了比较。     

高效阴离子交换-脉冲安培法测定化妆品中葡萄糖酸锌含量

建立了高效阴离子交换-脉冲安培法测定化妆品中葡萄糖酸锌的含量.样品用水超声提取后,离心取上清液过On Guard Ⅱ RP柱除去疏水性化合物,再经CarboPac PA1和CarboPacPA20保护柱分离,脉冲安培检测,葡萄糖酸锌在0.1～5.0mg/L范围内线性关系良好(r2=0.9999),加标回收率在98.9～107.7％之间,方法检出限为0.042mg/L,对应样品中检出限为4.2mg/kg,方法简单,灵敏度高.     

高效阴离子交换色谱-积分脉冲安培检测法分析糖类化合物影响因素的研究

研究了高效阴离子交换色谱-积分脉冲安培检测法分离测定糖类化合物的一些影响因素。这些因素包括NaOH淋洗液浓度、色谱柱温度和积分脉冲安培检测的采样电位。实验用AminoPac PA10阴离子交换柱分离糖类化合物。当NaOH淋洗液浓度增大时,糖类化合物的保留值减小,并有洗脱顺序的变化。糖的保留只表现为放热行为,但是每种糖的保留受温度的影响程度不同,即当温度改变时每种糖保留时间的变化程度不同。一般规律是随糖分子增大(依单糖、双糖、三糖、四糖顺序),其保留时间的变化程度增大。通过改变温度可以改善两种相近洗脱糖之间的分离状况。糖的范特霍夫(Van’t Hoff)曲线具有良好的线性关系。积分脉冲安培检测的采样电位增大,糖检测的峰面积增大。通过提高采样电位,可以改善糖的检测。     

Integrated pulsed amperometry for the analysis of organic compounds

Integrated pulsed amperometric detection (IPAD) was applied for the detection of organic compounds for flow injection analysis. The pulse waveform used in the integrated pulsed amperometry consisted of three steps: detection potential, oxidation potential, and adsorption potential. The pulse waveform was applied to the working electrode as the analyte flowed through the electrochemical cell. Unlike ordinary pulsed amperometry, a faradaic current was integrated over the duration period of the detection potential in the IPAD. Therefore, the total charge was measured by integrating the current after the detection potential was applied. The current for the initial 10 ms, after applying the detection potential, was excluded from the integration due to a large charging current at the initial period. Compared with pulsed amperometry, integrated pulsed amperometry provides a better signal-to-noise ratio and a lower detection limit. This method was applied to the quantitative analysis of thiourea as a representative analyte of organosulfur compounds in a flow injection analysis.     

Recent developments in electrochemical flow detections--a review part II. Liquid chromatography

This article is a review of the progress in application of electrochemical detections in liquid chromatography in recent 15–20 years. Based on 238 references, mostly to original research papers, it presents applications of amperometric and voltammetric detections, as well as coulometric, conductimetric and potentiometric ones. In case of those which have reached already the stage of routinely employed detections with commercially available instrumentation (amperometry, coulometry, conductometry) especially novel and original applications are presented. In case of voltammetric and potentiometric detections a ways of their improvements are showed, directed towards obtaining competitive results with other detection methods.     

Ion chromatographic analysis of amines, alkanolamines, and associated anions in concrete

In order to assess the effectiveness of applying penetrating corrosion inhibitors to the surface of reinforced concrete, it is necessary to devise accurate methods for their detection and quantification. In this paper, methods for ion chromatographic analysis of a variety of amines, alkanolamines, and associated anions, which may be used as corrosion inhibitors for steel reinforcement in concrete, are described. By careful adjustment of the conditions for analysis, these inhibitors were readily identified and quantified in concrete/cement pore solutions or digests. Characterisation of the cationic inhibitors, ethanolamine, quaternary methylammonium, dimethylethanolamine, cyclohexylamine, guanidine, and arginine, and the anionic inhibitors, nitrite, molybdate, acetate, benzoate, and azelate, was carried out conductimetrically. To enhance the sensitivity of detection, amperometry was used for the analysis of triethanolamine and low concentrations of ethanolamine. Ion chromatography was also used as a means of obtaining a distribution profile of the concentrations of inhibitor ions present throughout a concrete structure.     

Determination of aspartame by ion chromatography with electrochemical integrated amperometric detection

In this paper, the separation and determination of the sweetener aspartame by ion chromatography coupled with electrochemical amperometric detection is reported. Sodium saccharin, acesulfame-K and aspartame were separated using 27.5 mmol/l NaOH isocratic elution on a Dionex IonPac AS4A-SC separation column. Aspartame can be determined by integrated amperometric detection without interference from the other two sweeteners. The method can be applied to the determination of aspartame in powered tabletop, fruit juice and carbonated beverage samples, and the results obtained by integrated amperometry were in agreement with those obtained using a UV detection method. A method for determining analytes with an NH₂ group by ion chromatography with integrated amperometry was developed.     

New approach to the simultaneous analysis of catecholamines and tyrosines in biological fluids

New high-performance liquid chromatographic (HPLC) methods with amperometric-CoulArray detection were developed for simultaneous analyses of norepinephrine, epinephrine, L-DOPA, dopamine, 3-nitrotyrosine, m-, o-, and p-tyrosines. Overall, detection limit was in the low pmol range with amperometry, and in the low fmol range for the CoulArray method. Linear (r2 = 0.99) detector performances were observed in the ranges of 2-200 pmol with amperometry, and 0.2-20 pmol for the CoulArray method. Analytical precision values were better than 80 and 95% for HPLC-amperometry and HPLC-CoulArray method, respectively. These methods offer sensitivity, specificity, minimal sample requirement, and especially the HPLC-CoulArray method allows simultaneous assessment of various similar biomolecules.     

Selective detection of metal species in HPLC and FIA by means of pulsed amperometric detection (PAD)

Triple-step pulsed amperometry is used to detect selectively metal complex species after HPLC separation in the presence of coeluting matrix compounds. Optimized pulse parameters enable accurate and selective detection of species even in the presence of electroactive compounds such as phenols or sulfurcontaining peptides. Complexes of tin(IV) with rutin and of platinum(II) with glutathione are presented as examples for these classes of compounds. It is demonstrated that by changing the pulse waveform direct and indirect detection modes can be realized. The method is applied to detect platinum species in a grass extract and iron(II)-lactate in fruit juice. Furthermore it is shown, that pulsed amperometry can be used as a detector in FIA for determining the fraction of metal complex formed after mixing of metal and excess ligand without separation.     

毛细管电泳安培及电导检测最新进展

对毛细管电泳安培检测和电导检测的研究近况进行了综述,分别介绍了电导法和安培法与毛细管电泳的联接及应用,并对其发展方向作了展望。     

Determination of several sugars in serum by high-performance anion-exchange chromatography with pulsed amperometric detection

In this paper, a sensitive, simple and direct method for simultaneous determination of glucose, ribose, isomaltose and maltose in serum sample by high-performance anion-exchange chromatography coupled with integrated pulsed amperometric detection was developed. The four target analytes were easily and completely separated on an anion-exchange column at a flow-rate of 0.25 mL/min by binary step gradient elution in about 16 min and the two eluents were deionized water and 500 mM sodium hydroxide, respectively. The separated four analytes were detected directly by using a gold electrode and quadruple-potential waveform integrated pulsed amperometry without derivatization. Under the optimized conditions, when the injection volume was 25 microL, the detection limits (signal-to-noise ratio equal to 3) for glucose, ribose, isomaltose and maltose were 0.92, 7.50, 12.9 and 10.3 ng/mL, respectively. The calibration graphs of peak area for the four analytes were linear over two to three orders of magnitude with correlation coefficients greater than 0.998. R.S.D. of peak areas of the four analytes for five determinations were no more than 5.6%. The analytical method had been applied to the determination of glucose, ribose, isomaltose and maltose in real serum samples and good results with low relative standard deviation not more than 5.3% were obtained. The accuracy of the proposed method was tested by recovery measurements on spiked samples and good recovery results (98.1-107.9%) were obtained.     

Recent developments concerning the investigation of exocytosis with amperometry

In this article, we have summarized the recent important results related to the electrochemical detection of vesicular exocytosis by amperometry with microelectrodes over the past three years. In this fascinating scientific field that began 40 years ago, the historical carbon fiber amperometry method still continues to be used to address biological questions by the pioneered groups of the field but also by other research groups thus showing this has become an indispensable routine technique for analyzing exocytosis. Furthermore, new methodologies (coupling with fluorescence, use of nanoelectrodes, microarrays) have blossomed and demonstrated how new analytical methods could be built to push back the limits of the initial technique.     

Electrooxidation of ethylenediaminetetraacetic acid at a polycrystalline boron-doped diamond anode

Electrooxidation of ethylenediaminetetraacetic acid at a thin-film boron-doped polycrystalline diamond anode is studied by cyclic voltammetry and amperometry. It is shown that diamond electrodes can be used in the analytical determination of ethylenediaminetetraacetic acid: they have low background current; the detection limit is also rather low.