Determination of phenolic whitening agents in cosmetics by micellar electrokinetic capillary chromatography with amperometric detection

A sensitive method for simultaneous determination of six phenolic whitening agents,including arbutin, phenol,resorcinol,hydroquinone,kojic acid,and salicylic acid in cosmetics has been developed using micellar electrokinetic capillary chromatography with amperometric detection（MECC-AD）.Effects of several factors,such as the pH value and concentration of running buffer,potential applied to the working electrode,separation voltage,and injection time were investigated to obtain optimum conditions for separation and detection.With a 75 cm long fused-silica capillary tube,well-defined separation of six phenolic compounds was achieved in 10mmol/L SDS/40 mmol/L H₃BO₃-Na₂B₄O₇ running buffer（pH 9.0）.Good linear relationship was obtained for each analyte over three orders of magnitude with correlation coefficients（r2） between 0.9985 and 0.9994,and the detection limit（S/N=3） ranged from 0.04μg/mL to 0.45μg/mL The proposed method has been successfully applied for the determination of phenolic whitening agents in real cosmetic samples with satisfactory results,providing an alternative monitoring method for cosmetics safety regulation.     

Simultaneous determination of active ingredients in blueberry wine by CE-AD

A method based on capillary electrophoresis coupled with amperometric detection（CE-AD） has been developed for the separation and determination of kaempferol,ferulic acid,vanillic acid,caffeic acid,gallic acid and protocatechuic acid in blueberry wine for the first time.In order to get the optimum conditions of separation,the effects of working electrode potential,pH value and concentration of running buffer,separation voltage and injection time on CE-AD were investigated.Under the optimum conditions, the analytes could be separated in Na₂B₄O₇-KH₂PO₄ buffer at pH 7.8 within 18 min.A 300μm diameter carbon disk electrode had good current responses at +0.95 V（vs.SCE） for all analytes.The responses were linear with concentrations over three orders of magnitude with detection limits（S/N = 3） at 10^-8 g/mL magnitude for the analytes and the recoveries were in the range of 95.8- 106.7%.The method could be successfully applied to the analysis of real sample with satisfactory results and therefore recommended for use by the quality control departments of fruit wine producers.     

场放大样品进样-压力辅助毛细管区带电泳测定饮用水中的百草枯

1 引 言 百草枯属有机杂环类季铵盐除草剂,由于它具有优良的除草效果,已广泛应用于多种作物的杂草防治.百草枯具有极强的水溶性,极易迁移至水体环境中,从而对饮用水的质量安全构成潜在威胁.目前,百草枯的残留检测方法主要有分光光度法[1]、液相色谱-质谱联用法[2]、气相色谱质谱联用法[3]和毛细管电泳法(CE) [4～6].采用分光光度法测定百草枯,不仅操作繁琐费时,而且灵敏度低.采用气相色谱法测定百草枯,通常需要衍生化,应用较少[3].采用液相色谱法测定百草枯,通常需要在流动相中添加离子对试剂[2].毛细管电泳具有分离效率高,分析速度快等优点,已被广泛用于水样中百草枯残留的测定.然而,毛细管电泳灵敏度不高,极大地限制了其在实际样品分析中的应用.场放大样品进样(FASI)是一种简单有效的在线富集方法,其富集倍数可达1000倍[7],可有效提高毛细管电泳技术的灵敏度,因此应用较为广泛.本实验建立了场放大样品进样-压力辅助毛细管区带电泳法(CZE),用于测定饮用水中百草枯的残留量.     

Study on Rapid Determination of Aristolochic Acids in Aristolochia Medicinal Plants

Aristolochic acid (AA) composed of AA-Ⅰ and AA-Ⅱ (Fig. 1 ) is the major toxic component extracted from Aristolochia plants. Recently, it has been proved by several researches that high doses of aristolochic acids (AA) can result in a severe kidney disease named Chinese herbs ne-     

毛细管区带电泳技术快速分离检测爆炸残留物中的无机离子

利用间接紫外毛细管区带电泳方法完成了对爆炸残留物中7种无机离子(K+,NH+4,NO-2,NO-3,SO2-4,ClO-3,ClO-4)的分离检测。阳离子测定采用的缓冲体系为10 mmol/L吡啶（pH 4.5）-3 mmol/L冠醚,K+和NH+4在2.6 min内达到基线分离,检出限分别为0.25 mg/L和0.10 mg/L(S/N=3)。阴离子测定采用的缓冲体系为40 mmol/L硼酸-1.8 mmol/L重铬酸钾-2 mmol/L硼酸钠（pH 8.6）,氢氧化四甲铵为电渗流改性剂,5种阴离子在4.6 min内达到基线分离,检出限为0.10～1.85 mg/L。该方法已成功地应用于实际爆炸物样品种类的判定分析,取得了很好的结果。     

毛细管区带电泳技术快速分离检测爆炸残留物中的无机离子

利用间接紫外毛细管区带电泳方法完成了对爆炸残留物中7种无机离子(K+,NH+4,NO-2,NO-3,SO2-4,ClO-3,ClO-4)的分离检测。阳离子测定采用的缓冲体系为10 mmol/L吡啶（pH 4.5）-3 mmol/L冠醚,K+和NH+4在2.6 min内达到基线分离,检出限分别为0.25 mg/L和0.10 mg/L(S/N=3)。阴离子测定采用的缓冲体系为40 mmol/L硼酸-1.8 mmol/L重铬酸钾-2 mmol/L硼酸钠（pH 8.6）,氢氧化四甲铵为电渗流改性剂,5种阴离子在4.6 min内达到基线分离,检出限为0.10～1.85 mg/L。该方法已成功地应用于实际爆炸物样品种类的判定分析,取得了很好的结果。     

Chiral Separation of Ibuprofen and Terbutaline by Nonaqueous Capillary Electrophoresis with Conductance Detection

IntroductionThe separation of chiral substances is a chal-lenge task to analytical chemistry and pharmaceuti-cal chemistry.HPLC[1] and GC[2 ] are the commonchiral separation techniques.Unfortunately,theyare time- consuming and strenuous.In addition,thechiral separation columns are expensive and thebaseline separation is hard to be obtained.Recently,the researches of chiral separationwith capillary electrophoresis have been active[3 ,4 ] .However,the instrument with an optical detectorcosts …     

毛细管电泳电化学检测

综述了毛细管电泳的电化学检测,包括电位法、电导法和安培法检测的研究进展,重点讨论了电化学检测与毛细管电泳的耦联,并对电化学检测的原理及其应用进行了较详细的叙述,引用文献72篇。     

毛细管电泳与芯片毛细管电泳的双检测技术

综述了毛细管电泳和芯片毛细管电泳的3种双检测技术,包括荧光-散射等光学双检测技术、安培-非接触电导等电化学双检测技术和荧光-非接触电导等光电联用双检测技术.介绍了3种双检测方法的仪器的检测原理及应用,并展望了双检测技术的发展前景.引用文献54篇.     

动平衡毛细管电泳的研究进展

动平衡毛细管电泳(KCE)是一种既能测定配受体间相互作用热力学参数、还可获得配受体间动力学参数的新方法.本文对动平衡毛细管电泳的发展历史、作用模式和原理,以及动平衡毛细管电泳目前存在的一些问题进行了评述.     

用毛细管电泳法对某些药物的分离试验

本文采用毛细管电泳法,以50μm内径,45cm长的弹性石英毛细管作为分离管,选用磷酸盐-硼酸盐-十二烷基硫酸钠缓冲溶液体系,在柱254nm紫外检测器,在不同的电泳电压下,对水溶性维生素,磺胺类药物、头孢菌素抗生素,解热镇痛药物有效成份进行了分析,取得较满意的结果。     

对映异构体的高效毛细管电泳分离与测定

高效毛细管电泳是８０年代发展起来的一种高效、快速的新型分离技术，在对映异构体分离方面有着广泛的应用前景，本文介绍了这一新型分离技术用于对映体分离的基本原理，并列举了一些对映异构体分离的实例。     

毛细管电泳在线电推扫测定蔬菜中3种氯化烟碱类农药残留

以采用电动进样模式的毛细管电泳在线电推扫技术建立了测定蔬菜中吡虫啉、啶虫脒和噻虫嗪残留的新方法.研究了缓冲液浓度、pH值、十二烷基硫酸钠浓度、分离电压和进样量对峰高的影响,优化后缓冲液为40 mmol/L硼酸盐、60 mmol/L十二烷基硫酸钠、pH 7.8,进样电压10 kV,进样时间120 s,分离电压25 kV.在此条件下,吡虫啉、啶虫脒和噻虫嗪的富集倍数可达626,788和443倍;检出限分别为5.6,2.9和2.5 μg/kg;相对标准偏差为1.65%,1.92%和0.96%;平均加标回收率为87.4%～102.5%,95.3%～103.1%和78.7%～93.9%.本方法可满足相关标准中的残留限量要求,已用于蔬菜中这3种农药残留的检测.     

非水体系毛细管电泳-紫外检测法测定对乙酰氨基苯酚的研究

本文报道了用非水相体系高效毛细管电泳-紫外检测法测定对乙酰氨基苯酚的新方法;考察了运行电压、非水相介质和电解质等因素的影响。在25℃下,以50mmol／L NaOH的乙醇溶液为电泳缓冲介质,30mmol／L乙酸钠的乙醇溶液为样品溶剂;选择重力进样30S,运行电压-25kV,及检测波长250nm。测定对乙酰氨基苯酚的线性范围为5．2～52μg／mL;检出限为2．88μg／mL;RSD为2．34％。本法应用于维C银翘片中对乙酰氨基苯酚的测定,结果满意。     

高效毛细管电泳的电导检测和紫外光度检测研究

本文自制商效毛细管电泳装置.研究了毛细管区带电泳电导检测和毛细管胶束电动色谱紫外光度检测。在电导检测中,制作铂丝微电导池,并由用电池隔膜制作的导电接口连接电泳毛细管和电导池,高压被有效隔离,实现柱后电导检测,用内径200μm、长70cm(到接口)石英毛细管在10kV电压下分离检测Li~-、Na~-、K~-。在电动色谱中将高效液相色谱仪与高压电源组成电泳装置,用内径100μm,长50cm(到检测器)石英毛细管和SDS胶束溶液在14kV电压下分离检测电中性化合物。     

毛细管电泳法测定双氢青蒿素的含量

使用自行设计的毛细管电泳柱端安培检测系统,在乙醇为有机添加剂的条件测定了双氢青蒿素。研究了工作电极、缓冲溶液浓度及其pH、有机溶剂的选择及其含量、检测电位和分离高压对测定的影响。结果表明：选用Ag工作电极,检测电位为-O．6V,在20mmol／L硼砂,pH为9的运行介质的优化条件下,双氢青蒿素在4min左右出峰,在1～200mg/L范围内,峰高与浓度呈良好的线性关系,检出限为O．05mg/L。     

毛细管区带电泳在氧氟沙星含量分析中的应用

氧氟沙星（ＯＦ）是第三代喹诺酮类药物中效果最好的广谱抗菌素之一。由于它在ｐＨ２～１１范围内难溶于水与醇，给用ＨＰＬＣ法检测其含量带来一定困难。本文报告了用毛细管区带电泳（ＣＺＦ）分离检测该药的方法。由于使用ｐＨ调制样品引入技术，克服了其溶解性不好给ＨＰＬＣ法所带来的困难。其实验条件为：５０ｍｍｏｌ／Ｌ硼砂（ｐＨ１．５）为电泳缓冲液，２８０ｎｍ为紫外检测波长，２５ｋＶ为电泳电压。样品由高差进样方式引入分离毛细管（５．１２ｃｍ×５０μｍｉ．ｄ．，有效分离长度为３８．５ｃｍ）。用磺胺作内标，ＯＦ在４８～５３０ｍｇ／Ｌ及５８０～９７０ｍｇ／Ｌ范围内可进行定量分析。保留时间（ｔｒ）及相对紫外吸收（Ａ（样品）／Ａ（内标））的日内－ＲＳＤ值分别小于１．０％和２．４％（ｎ＝６）。     

毛细管胶束电动色谱分离测定大米中农药类环境激素乐果、克百威和灭多威残留

用毛细管胶束电动色谱分离测定了3种农药类环境激素乐果、克百威和灭多威在大米中的残留。考察了电泳缓冲溶液的pH值、浓度及表面活性剂浓度等影响因素,在pH=7.0的20mmol/L硼酸-四硼酸钠缓冲溶液+70mmol/L十二烷基硫酸钠(SDS)+10%甲醇体系中,三组分在16min内得到基线分离。乐果、克百威及灭多威的检测限分别为0.01、0.02和0.008mg/kg,回收率范围为101.31%～102.63%,相对标准偏差(RSD)<5%。该方法具有操作简单、快速、重现性好等优点。     

Capillary electrophoresis-based methods for the determination of lipids--a review

Capillary electrophoresis (CE) is a high-resolution technique for the separation of complex biological and chemical mixtures. CE continues to emerge as a powerful tool in the determination of lipids. Here we review the analytical potential of CE for the determination of a wide range of lipids. The different classes of lipids are introduced, and the different modes of CE and optimization methods for the separation of lipids are described. The advantages and disadvantages of the different modes of CE compared to traditional methods like gas chromatography (GC) and liquid chromatography (LC) in the determination of lipids are discussed. Finally, the potential of CE in the determination of lipids in the future is illustrated.     

Determination of piribedil in pharmaceutical formulations by micellar electrokinetic capillary chromatography

A fast and simple micellar electrokinetic capillary chromatographic method was developed for the analysis of piribedil in pharmaceutical formulations. The effects of buffer concentration, buffer pH, sodium dodecyl sulphate (SDS) concentration, organic modifier, applied voltage and injection time were investigated. Optimum results were obtained with a 50 mM borate buffer at pH 8.0 containing 50 mM SDS by using a fused silica capillary (50 m internal diameter, 72 cm effective length). The sample was injected hydrodynamically for 4 s at 50 mbar pressure and the applied voltage was +30 kV. The detection wavelength was set at 205 nm. Diflunisal was used as an internal standard. The analysis was performed at 25 °C and the total run time was 14 min. The method was suitably validated with respect to linearity range, limit of detection and quantification, precision, accuracy, specificity and robustness. The linear calibration range was 5–100 g mL^–1 and the limit of detection was determined as 1 g mL^–1. The method developed was successfully applied to the determination of piribedil in pharmaceutical formulations. The results were compared with a spectrophotometric method reported in the literature and no significant difference was found statistically.