毛细管电泳中影响径向电场控制电渗的主要因素

利用自制的二维电场毛细管电泳系统研究了不同因素对径向电场控制电渗能力的影响,发现缓冲液的ｐＨ值、浓度、种类以及管壁表面状态、管径等对电渗的电场调控有关键性的影响。有趣的是,添加剂不影响电场的调控能力,而杯芳烃涂层毛细管却能提高电渗对径向电场的响应能力。利用这种涂层效应有可能实现较高ｐＨ值下电渗的电场调控。     

毛细管区带电泳法测定血浆中的苯妥英钠

 建立了以毛细管区带电泳测定血浆中苯妥英钠含量的方法。此法具有良好的重现性和线性关系 ,日内、日间的平均相对标准偏差分别为 3.1%和 4 .7% ,平均回收率大于 95 % ,标准曲线的相关系数为 0 9985 ,是一种简便、快速、准确、灵敏的测定方法 。     

Simultaneous determination of paraquat and diquat in serum using capillary electrophoresis.

The use of capillary electrophoresis for simultaneous separation and detection of the two bipyridylium herbicides, paraquat and diquat, was investigated. Both herbicides were extracted from fortified sera with disposable ODS-silica cartridges. Separation was carried out using a capillary tube (50 microns i.d., 750 mm) of fused silica containing 10 mM glycine-HCl buffer (pH 3.0), 40 mM NaCl and 20% methanol as the carrier. Paraquat and diquat were completely separated in 10 min at an applied potential of 20 kV. On-column UV monitoring allowed detection of both herbicides simultaneously. The assay sensitivity was 0.05 micrograms/mL (signal-to-noise ratio, 2:1), which probably increases with increase in the sample volume of serum. Analytical recovery of both herbicides added to serum was about 97% at concentrations of 0.5-2.0 micrograms/mL.     

胶束电动毛细管色谱法测定消糖灵中的优降糖

 以甲氧苄氨嘧啶为内标,采用胶束电动毛细管色谱法分离测定了新药消糖灵中的优降糖。电泳条件：以25 mmol/L硼砂-30 mmol/L十二烷基硫酸钠（pH 9.0）为电泳介质,未涂层石英毛细管（50 μm i.d.×39.5 cm,有效分离长度34.8 cm）为分离通道,压力进样(68.95 kPa.s),17 kV恒压电泳（28 ℃）,检测波长228 nm。优降糖在14 min内与其他成分得到很好分离,且质量浓度为25 mg/L～275 mg/L时,优降糖可进行定量分析,加标回收率为(100.6±1.4)%。方法简便、快速,结果准确,重现性好,可用于优降糖复方制剂的质量控制。     

毛细管区带电泳法测定葡萄籽中儿茶素类化合物

 采用毛细管区带电泳法测定了 10种中国产葡萄籽中的 4个主要儿茶素类化合物 :(+)儿茶素、(- )表儿茶素、(± )表没食子儿茶素、(± )表儿茶素没食子酸酯的含量。在 0 0 2mol/L硼砂和 0 0 0 5mol/L磷酸盐的混合缓冲体系 (pH 10 0 )的背景缓冲液中 ,4个化合物在 10min内取得了令人满意的分离。迁移时间的重现性(RSD)小于 2 % ,峰面积的重现性 (RSD)小于 5 %。在质量浓度为 0 0 0 5g/L～ 0 5 g/L时 ,线性相关系数大于0 995。检测限为 3mg/L～ 10mg/L。该方法简单、快速、准确 ,可作为葡萄籽分析和药用开发过程中分析儿茶素类化合物的有效方法推广使用。     

固相萃取和高效液相色谱相结合快速测定苦瓜甙A的含量(英文)

 建立了一个快速、简单、准确的固相萃取和高效液相色谱相结合的测定苦瓜甙A含量的方法。样品经石墨碳固相萃取管 (3mL/ 2 5 0mg)纯化后以高效液相色谱检测。色谱柱为C18,流动相为V(乙腈 )∶V(甲醇 )∶V(5 0mmol/L磷酸二氢钾缓冲液 ) =2 5∶2 0∶6 0 ,流速为 0 .8mL/min ,检测波长为 2 0 8nm。标准曲线自 10mg/L到 10 0 0mg/L呈线形关系 (r2 =0 .9992 )。该方法具有很好的重现性 ,日内或日间的相对标准偏差和相对平均误差均小于 10 %。样品回收率大于 90 %。     

气相色谱法直接测定植物生长素

 建立了一种采用 5 3 0 μm大口径毛细管色谱柱、不经衍生化处理而直接测定吲哚乙酸 (IAA)、吲哚丁酸(IBA)和萘乙酸 (NAA)等植物生长素的气相色谱分析方法。以邻苯二甲酸二丁酯为内标物 ,用 FID检测 ,IAA,IBA和 NAA的相对标准偏差分别为 1 .1 4% ,0 .61 %和 0 .78%。方法简便、快速、准确、重现性好 ,可用于生长素类单组分和混合制剂的质量检测。     

Side-entry excitation and detection of square capillary array electrophoresis for DNA sequencing.

In high throughput DNA sequencing based on capillary electrophoresis, efficient coupling of the laser to each capillary is a challenge. Our group previously reported two multiple point irradiation schemes. The present work describes a more efficient excitation and detection method in which the laser light propagates through the capillary array without undergoing a serious reduction in power. An array of square capillaries (340 microns O.D. x 75 microns I.D.) was sandwiched between two fused-silica plates with an index-matching solution in between. The light was directed into the channel across the capillary array from the side. DNA sequences of PGEM/U from 24 capillaries were obtained even with a relatively low-power laser. The excitation scheme can be scaled up to hundreds of capillaries to achieve high-speed, high-throughput DNA sequencing, genetic typing and drug screening.     

反相高效液相色谱法测定罐头食品中乙二胺四乙酸的残留量

 将罐头食品捣碎后用水稀释,加氯化铜溶液和抗坏血酸,用水定容,过0.45 μm滤膜后立即供液相色谱分析,在254 nm波长处测定。色谱柱：Hypersil ODS(125 mm×4 mm i.d., 5 μm);流动相：水-甲醇（体积比为80∶20）,含有20 mmol/L四丁基溴化铵,0.03 mol/L 醋酸钠缓冲液（pH 4） ,流速：0.8 mL/min;进样量：20 μL。EDTA在10 mg/L～400 mg/L范围内呈线性。方法回收率为95.5%～98.9%,其RSD为0.82%～1.32%。     

Capillary waveguide fluoroimmunosensor with improved repeatability and detection sensitivity

An optical capillary waveguide fluoroimmunosensor based on glass capillaries internally coated with an ultrathin poly(dimethylsiloxane) (PDMS) film is presented. The evaluation of the capillaries developed was done in comparison with aminosilanized [3-(aminopropyl)triethoxysilane, APTES] glass and poly(methylpentene) (PMP) capillaries by immobilizing rabbit γ-globulins on the internal capillary wall. Following reaction with (R)-phycoerythrin-labelled antibody, the capillary was scanned with a laser beam and the fluorescence waveguided through the capillary wall was detected by a photomultiplier placed at one of its ends. The capillaries developed provided considerably improved protein coating homogeneity (intracapillary coefficients of variation 2.9–6.6%) and repeatability (intercapillary coefficients of variation 2.1–5.0%) compared with APTES-treated ones (7.9–13.4 and 8.5–15.2%, respectively). With use of these capillaries in a sandwich-type immunosensor for the determination of rabbit γ-globulins, the assay detection limit was improved eightfold (4.4 ng/mL) compared with that obtained using PMP capillaries (35.3 ng/mL), whereas the assay repeatability was improved threefold (intra-assay coefficients of variation 5.9–13.1%) compared with APTES-treated capillaries (15.6–36%). Optoelectronic set-up used to scan the capillaries (left) and representative fluorescence scannings of dual-band poly(methylpentene) (PMP), PDMS-modified glass and APTES treated glass capillaries     

On-line cation-exchange preconcentration and capillary electrophoresis coupled by tee joint interface

An on-line preconcentration method based on ion exchange solid phase extraction was developed for the determination of cationic analytes in capillary electrophoresis (CE). The preconcentration-separation system consisted of a preconcentration capillary bonded with carboxyl cation-exchange stationary phase, a separation capillary for zone electrophoresis and a tee joint interface of the capillaries. Two capillaries were connected closely inside a 0.3 mm i.d. polytetrafluoroethylene tube with a side opening and fixed together by the interface. The preparations of the preconcentration capillaries and interface were described in detail in this paper. The on-line preconcentration and separation procedure of the analysis system included washing and conditioning the capillaries, loading analytes, filling with buffer solution, eluting analytes and separating by capillary zone electrophoresis (CZE). Several analysis parameters, including sample loading flow rate and time, eluting solution and volume, inner diameter and length of preconcentration capillary etc., were investigated. The proposed method enhanced the detection sensitivity of CE-UV about 5000 times for propranolol and metoprolol compared with normally electrokinetic injection. The detection limits of propranolol and metoprolol were 0.02 and 0.1 microg/L with the proposed method respectively, whereas those were 0.1 and 0.5 mg/L with conventional electrokinetic injection. The experiment results demonstrate that the proposed technique can increase the preconcentration factor evidently.     

高效毛细管区带电泳法分离人血清蛋白质的研究

 研究了高效毛细管区带电泳分离人血清蛋白质的电泳行为及实验条件 ,建立了分离血清蛋白质的高效毛细管区带电泳法。血清样品经硼酸缓冲液 (5 0 mmol/L,p H8.80 )稀释后 ,以 0 .1 mol/L硼酸缓冲液 (p H9.3 5 ,含4g/L PEG80 0 0 )为电泳介质 ,在 5 0 μm i.d.× 3 7cm弹性石英毛细管柱 (有效柱长为 3 2 cm)中进行电泳分离 ,以2 0 0 nm紫外波长检测。方法简便、快速、重复性好 ,1 2 min内便可完成对血清中蛋白质的电泳分离。     

Electroosmotic flow changes due to interactions of background electrolyte counter-ions with polyethyleneimine coating in capillary zone electrophoresis of proteins

The properties and behavior of polyethyleneimine (PEI) covalently coated capillaries with respect to different background electrolytes used in capillary zone electrophoresis (CZE) are described. The coating stability and changes of inner surface charge in the capillary were followed by measurement of electroosmotic flow (EOF). Interest was focused mainly on conjugate bases of carboxylic acids as anionic background electrolyte components (acetate, citrate, malate, malonate, tartrate, and succinate). An interesting phenomenon was observed in PEI-coated capillaries: The direction (and the magnitude) of EOF depends on the composition of the background electrolyte and at a certain pH it can undergo reversible change. Ionic complex formation was suggested as a hypothesis to explain this behavior. With this knowledge, the PEI-coated capillary was used for the separation of basic proteins in the above-mentioned background electrolytes. A standard protein mixture of cytochrome c, ribonuclease A, and lysozyme at a concentration of 0.25 mg/mL each was chosen as model sample.     

高效毛细管电泳法同时测定多种肽类药物的方法研究

  以血管紧张素Ⅰ,Ⅱ,Ⅲ和P物质、神经激肽、生 长激素释放的抑制因子、神经紧张肽等7种肽类药物混合物为测定对象,用胺涂层的毛细管 柱(57 cm×75 μm i．d．,有效长度为50 cm)对上述混合物的分离条件进行了研究。在 f工作电压为10 kV［（－）→(＋)］、电流为42 μA、检测波长为214 nm、测定温度为2 5 ℃、虹吸进样10 s的条件下,在50 mmol/L的醋酸铵缓冲液(pH 4.5)中,上述混合物可在8 min内得以完全分离。 关键词：     

Determination of quinolizidine alkaloids in Sophora flavescens and its preparation using capillary electrophoresis

A simple and accurate capillary electrophoresis method was developed for the determination of four quinolizidine alkaloids in Sophora flavescens and Kuhuang injection. Optimum separation of the analytes was obtained on a 65 cm x 75 microm i.d. uncoated fused-silica capillary using a aqueous buffer system of 60 mmol L(-1) sodium borate at pH 8.5, with applied voltage and capillary temperature of 12 kV and 25 degrees C, respectively. Detection wavelength was set at 204 nm and jatrorrhizine was used as the internal standard. Good linear relationships between peak-area ratios and concentrations of the analytes were observed over the concentration range 0.044-0.792 mg mL(-1) for matrine, 0.142-1.926 mg mL(-1) for oxymatrine, 0.0377-0.3393 mg mL(-1) for sophocarpine and 0.0664-1.062 mg mL(-1) for sophoridine. The recoveries of four alkaloids ranged between 93.08 and 101.4% with relative standard deviations from 0.7 to 9.2% (n = 6) as determined by standard addition. The limits of detection for four alkaloids were determined to be over the range 8.8-48.0 microg mL(-1). Contents of four alkaloids in Sophora flavescens and three alkaloids in Kuhuang injection were successfully determined under the optimum conditions.     

银黄冲剂中黄芩甙和绿原酸的毛细管电泳分离分析

摘要：用毛细管电泳法分离并测定了银黄冲剂中黄芩甙和绿原酸。以对硝基苯甲酸为内标,未涂层融硅毛细管（50μmi.d.,370μmo.d.,总长47cm,有效分离长度40cm）为分离通道,25mmol/L硼砂缓冲液（pH8.5）为电泳介质,17kPa·s压力进样,25kV恒压电泳,310nm检测。黄芩甙和绿原酸线性范围分别为160～960mg/L(r=0.9993,RSD=1.76％～2.33％）和80～960mg/L（r=0.9989,RSD=1.07％～2.51％）,加入回收率：黄芩甙为（102.09±1     

高效液相色谱法测定食品中的香豆素

介绍了用反相高效波相色谱（RP－HPLC）测定食品中香豆素含量的方法。样品用无水乙醚萃取,在40℃水浴上用氮气吹干,残留物用V（甲醇）：V（水）=9：1反萃取,用RP－HPLC定量分析。方法最小检出限为0.015mg／L,在2～10mg／L范围内有良好的线性关系,测定准确、重现性好,回收率为97.6％～100．8％,方法可行。     

毛细管电泳法测定白头翁汤中黄连和黄柏共煎生物碱的煎出量

 建立了利用毛细管电泳简便、准确地测定白头翁汤中黄连和黄柏共煎生物碱煎出量的方法。采用自组装毛细管电泳装置,采用75μmi.d.×50cm弹性石英毛细管,以0 05mol/LNa2B4O7 CH3OH(体积比为85∶15)溶液作缓冲液,运行电压为14kV,检测波长为232nm。另外,通过实验优化了提取溶剂中乙醇的含量。实验结果表明:以小檗碱、巴马汀提取量为指标,30%(体积分数)的乙醇水溶液是提取白头翁汤中黄连和黄柏共煎生物碱的最佳溶剂。小檗碱和巴马汀的质量浓度分别在15 0mg/L～65 0mg/L、12 5mg/L～50 0mg/L时与其峰面积有良好的线性关系;小檗碱的平均回收率不低于95%。     

Characterizing the adsorption of proteins on glass capillary surfaces using electrospray-differential mobility analysis

We quantify the adsorption and desorption of a monoclonal immunoglobulin-G antibody, rituxamab (RmAb), on silica capillary surfaces using electrospray-differential mobility analysis (ES-DMA). We first develop a theory to calculate coverages and desorption rate constants from the ES-DMA data for proteins adsorbing on glass capillaries used to electrospray protein solutions. This model is then used to study the adsorption of RmAb on a bare silica capillary surface. A concentration-independent coverage of ≈4.0 mg/m(2) is found for RmAb concentrations ranging from 0.01 to 0.1 mg/mL. A study of RmAb adsorption to bare silica as a function of pH shows maximum adsorption at its isoelectric point (pI of pH 8.5) consistent with literature. The desorption rate constants are determined to be ≈10(-5) s(-1), consistent with previously reported values, thus suggesting that shear forces in the capillary may not have a considerable effect on desorption. We anticipate that this study will allow ES-DMA to be used as a "label-free" tool to study adsorption of oligomeric and multicomponent protein systems onto fused silica as well as other surface modifications.     

Analysis and quantitation of rotenoids and flavonoids in Derris (Lonchocarpus urucu) by high-temperature high-resolution gas chromatography

A glass capillary column coated with PS-086 (15% phenyl-80% methylpolysiloxane, 15 m x 0.30-mm i.d., 0.1-microm film thickness) is used to analyze extracts from Lonchocarpus urucu (Derris urucu). Several secondary metabolites (8 flavonoids, 10 rotenoids) are characterized without derivatization, and the rotenoids are quantitated by high-temperature high-resolution gas chromatography (HTHRGC) and HTHRGC coupled with mass spectrometry (HTHRGC-MS). The limit of detection in flame ionization detection of rotenone is approximately 0.5 microg/mL, and the limit of quantitation was 2 microg/mL. Derris urucu bark is an excellent source of rotenone isomers (80 mg/g), deguelin (30 mg/g), and rotenolone (26 mg/g). Single solvent extractions (hexane, methylene dichloride, acetone, or methanol) are not able to fully extract the flavonoids and rotenoids. Complete extraction is achieved using a mixture of methanol-methylene dichloride (1:1), indicating a complex association of these compounds with the plant tissue. HTHRGC and HTHRGC-MS are shown to be quick and informative tools for the rapid analysis of crude extracts without the need for prior derivatization and fractionation.