几种核苷的毛细管胶束电动色谱分离

在胶束电动色谱模式下,考察了影响核苷分离的缓冲溶液、SDS浓度、pH、表面活性剂、有机添加剂、分离温度及外加电压等重要因素,并优化了关键的分离条件,建立了一种简单快速的利用毛细管胶束电动色谱DAD检测器分离分析核苷的新方法。当缓冲溶液为36 mmol/L硼酸缓冲液(pH 9.0)、30 mmol/L SDS和3%(V/V)乙腈,分离电压为25 kV和分离温度为25℃时,5种核苷在6 m in内实现了令人满意的基线分离。在优化的条件下,对其线性范围、检出限和重现性进行了测定。结果表明,核苷的迁移时间的重现性<1%;面积的重现性<3%。所建立的分离方法的线性范围宽,检出限低,重现性好。     

毛细管胶束电动色谱在扁桃酸合成中的应用

扁桃酸是药物中间体,可以苯甲醛为原料在相转移催化剂作用下合成制得.为了选择最佳合成条件,提高扁桃酸的转化率,需要对合成过程中各组分的含量进行快速测定,及时指导最优合成条件的选择.产品扁桃酸中可能含有未反应的苯甲醛和副产品苯甲酸、苯甲醇等杂质.以往采用非水溶剂酸碱滴定分析法测定产品中扁桃酸的含量,但当产品中有苯甲酸等酸性物质存在时,会使测定结果偏高.由于待测样品中组分扁桃酸、苯甲酸酸性使沸点较高,     

胶束电动力学毛细管色谱法测定尿中核苷

用胶束电动力学毛细管色谱法测定尿中核苷.通过苯基硼酸亲和色谱柱对尿中核苷进行纯化,以十二烷基磺酸钠(SDS)-十水合四硼酸钠-磷酸二氢钠为缓冲液(pH=6.96),在未涂层石英毛细管上,于7kV恒压,29℃下进行电泳分离,检测波长为254nm.此方法用于28个正常人尿中14种核苷的测定,确定了正常成年人(汉族)尿中核苷的排放范围.     

胶束扫集-电动色谱分离-毛细管电泳法测定升麻中三种有机酸含量

采用电场增强胶束扫集-电动色谱-毛细管电泳法对升麻中异阿魏酸、阿魏酸和咖啡酸的含量进行了测定,电泳缓冲体系为90 mmol·L~(-1)SDS-20 mmol·L~(-1)NaH_2PO_4(pH 2.20)-甲醇(10+90),分离电压为20 kV,检测波长214 nm。在优化的试验条件下,胶束扫集-电动色谱法对异阿魏酸、阿魏酸和咖啡酸富集倍数为4.3,4.8,2.9,3种有机酸均在14 min内出峰,线性范围分别为0.50～20.0,0.50～20.0,1.0～40.0 mg·L~(-1)。应用此方法分析了升麻样品并进行了回收率和精密度试验,测得回收率在93.2%～113.3%之间,测定值的相对标准偏差(n=5)小于6%。     

苯胺类化合物的胶束电动毛细管色谱优化分离

研究了用胶束电动毛细管色谱分离对-氯苯胺、对-溴苯胺、2,4-二氯苯胺、对-碘苯胺;在选定的实验条件下,各化合物迁移时间的相对偏差(RSD)＜0.5%,峰面积RSD＜3.0%,苯胺化合物的检出限为(1.2～4.2)×10-6mol/L;方法用于实验室废水分析,结果令人满意.     

毛细管胶束电动色谱对复方药物有效成分的定量研究

本文报道采用毛细管胶束电动色谱法对复方药物去痛片和感冒灵中有效成分进行了分离和定量研究。以0.05毫米内径、45厘米长的弹性石英毛细管为分离柱,用十二烷基硫酸钠胶束溶液,在选定的实验条件下,各组分在十几分钟内就能很好的分离。采用两点内标法定量,所得结果与HPLC法测定结果相一致。该法具有装置简单,无需价格昂贵的分离柱,样品预处理简单等优点,可在药物分析中推广。     

电动流动分析-胶束电动毛细管色谱联用测定食品防腐剂

采用电动流动分析(EFA)和胶束电动毛细管色谱(MEKC)联用系统测定了食品中的防腐剂.EFA系统设备简单便携、易于实现自动化.EFA由一台自制电渗泵、5个电磁切换阀(由计算机通过自制接口卡和自编VC语言程序控制)和一个固相萃取微柱组成,采用EFA-MEKC低试剂消耗接口,可减少含贵重试剂的缓冲液消耗.MEKC缓冲溶液为100 mmol/L十二烷基硫酸钠(SDS) 20 mmol/L Na2B4O7(pH 9.3).使用对羟基苯甲酸(PBA)为内标物,方法可在15 min内分离测定6种防腐剂,峰面积相对标准偏差小于3.4%;检出限范围为0.04～0.1 mg/L;实际样品的回收率为91.4%～104%.     

Micellar Electrokinetic Chromatography of X-Ray Film Developing Baths

A simple and fast micellar electrokinetic chromatographic (MEKC) method for the determination of five main compounds (hydroquinone, metol, phenidone, 2-hydroxy-5-methylaminobenzenesulphonate and 2,5-dihydroxybenzenesulphonate) in X-ray film developing solutions was developed. The optimal conditions for the separation were established by varying the concentration of sodium dodecyl sulfate (SDS), the electrolyte pH and the temperature. Successful results were obtained with a 25mmolL^–1 Tris-phosphate buffer at pH 9.0 in the presence of 50mmolL^–1 SDS using direct UV detection at 214nm. Under these conditions, baseline separation of the five compounds was achieved in less than 8min. The method was validated in terms of precision, linearity, accuracy, and successfully applied to the analysis of X-ray film developing baths.     

Micellar Electrokinetic Chromatography of Cephalosporin Antibiotics

A simple micellar electrokinetic chromatographic (MEKC) method is described for the simultaneous separation of twelve cephalosporin antibiotics. The separation was performed in a phosphate buffer (0.1 M, pH 6.6) with sodium dodecyl sulfate (SDS) (0.1 M) as an anionic surfactant. The complete separation of twelve cephalosporins was attained in 36 min. Application of the method to the quantitative analysis of cefuroxime, cephalexin, cephapirin and cephradine in pharmaceutical preparations was demonstrated.     

电中性物质的毛细管胶束电动色谱

在自制的高效毛细管电泳装置上,使用内径为0.05毫米,长为450毫米的熔融石英毛细管,十二烷基硫酸钠胶束溶液,254nm检测波长,进行了电中性化合物的毛细管胶束电动色谱研究。并将乙醇-水混合溶剂引入体系,成功地进行了多环芳烃的分离。考察了电场强度,SDS浓度及乙醇含量对柱效的影响。     

5种生物胺的毛细管胶束电动色谱分离

在胶束电动色谱模式下考察了影响生物胺分离的几个因素(如缓冲溶液及SDS浓度、pH、表面活性剂、分离温度及外加电压等)并优化了分离条件,建立了一种简单快速的利用毛细管胶束电动色谱DAD检测器分离分析生物胺的新方法。当缓冲溶液为40mmol/L硼酸缓冲液(pH8.5)、68mmol/LSDS,分离电压为25kV、分离温度为25℃时,5种生物胺在7min内实现了令人满意的基线分离。在优化的条件下,对其线性范围、检出限和重现性进行了测定。结果表明,生物胺的迁移时间的重现性<0.8%,面积的重现性<4%。     

胶束电动毛细管电泳同时测定饮料中的多种添加剂

建立了分析饮料中山梨酸,苯甲酸,１０－羟基基癸烯酸,咖啡因和糖精钠五种添加剂的胶束电动细管电泳法。讨论了电压,缓冲溶液浓度和ＰＨ值,胶束浓度对分析结果的影响。５种添加剂的迁移时间和测定回收率的变异系数分别小于１．５％和５％,检测限分别为１０,１０,５,１０,２０μｇ／ｋｇ。     

Roles of Organic Modifiers in Micellar Electrokinetic Capillary Chromatography

In the present work, four organic modifiers, viz. urea, dioxane, methanol, and tetrahydrofuran, were comparatively and systematically studied in terms of their effects on electrokinetic migration behavior and the retention mechanism of homologous solutes in MECC. The results showed that the electroosmotic mobility, μ_eo, and the electrophoretic mobility of a micelle, μ_ep,mc, decrease linearly with increasing organic modifier concentration. The ability of organic modifiers to lower μ_eo is greater than their ability to lower μ_ep,mc. The negative values of the slopes of these linear relationships, D_eo and D_ep,mc, increase along the series the order urea < methanol < dioxane < tetrahydrofuran. The logarithm of the capacity factor (ln k′) of uncharged homologous solute, which is mainly determined by the hydrophobic interaction, decreases linearly with increasing organic modifier concentration, due not only to the decrease in the partition coefficient but also to the decrease in the phase ratio. A linear relationship was observed between the slope of the plot of ln k′ vs. organic modifier concentration and the carbon number of homologous compound. The slope of such a relationship can characterize the hydrophobicity of the organic modifier. The hydrophobicity of such organic modifiers is also found to increase along the series urea < methanol < dioxane < tetrahydrofuran.     

毛细管胶束电动色谱分离苯胺及甲基苯胺位置异构体

芳香胺类化合物作为一类环境科学必须检测的有机污染物,对其分析测定方法的研究已有很多报道,主要是气相色谱法[1-5],液相色谱法[6-9]以及薄层色谱法[10]。气相色谱法通常需要进行程序升温和样品富集,而且分析温度高,分析程序复杂;液相色谱法需要使用大量对健康有害的有机溶剂,     

竹荪加工中废弃物多糖水解液的胶束毛细管电泳研究

本文建立了胶束毛细管电泳测定竹荪加工废弃物的多糖组成的新方法。考察了缓冲溶液、表面活性剂、运行电压、温度等因素对分离效果的影响。选择25mmol/L硼酸盐(pH=9.4)-20mmol/L十二烷基磺酸钠(SDS)为电泳介质,分离电压为15kV,分离温度为25℃,9min中内可实现对竹荪加工中废弃物中多糖的单糖组分的分离检测。     

毛细管胶束电动色谱在线高盐堆积技术检测3-硝基酪氨酸

利用毛细管胶束电动色谱在线高盐堆积技术研究NaNO2-H2O2-氯高铁原卟啉(hemin)-酪氨酸(tyro-sine)体系中3-硝基酪氨酸(3-NT)的测定,建立了一种新的测定生物样品中微量3-NT的方法。最佳分离条件为:含SDS(30mmol/L)的Na2B4O7(36mmol/L)缓冲液(pH9.3),进样压力为3.4kPa,进样时间为30s,毛细管柱温度25℃,分离电压20kV,样品中NaCl100mmol/L。在此条件下,3-NT检出限为0.1μmol/L(S/N=3);线性范围为0.78～50μmol/L;线性相关系数为0.9953。保留时间日内与日间的RSD(n=5)分别为1.6%和2.8%,加标回收率为95.2%～103.1%;样品不同浓度添加水平的日内和日间的RSD(n=5)均小于3%。本方法简单、快速、灵敏度高,为直接分析生物样品中的微量3-NT提供了方法。     

非离子表面活性剂Tween 20的胶束电动毛细管色谱分离

采用非离子表面活性剂Tween20胶束电动毛细管色谱法(MEKC),成功分离了莨菪亭、芸香苷和七叶亭3种多酚化合物。分离缓冲液为50mmol/LTween20 60mmol/LNa2B4O7(pH9.4)溶液,并用示差分光光度法测定Tween20与芸香苷和七叶亭的反应平衡常数和结合比,反应平衡常数分别为4.53×105和2.23×105(L/mol)2,结合数均为n=2。结果表明:Tween20-MEKC分离3种多酚是基于多酚与Tween20结合作用和电泳淌度的差异。     

Separation of Six Pyridoncarboylxic Acid Derivatives by Micellar and Microemulsion Electrokinetic Chromatography

Micellar electrokinetic chromatography (MEKC) and microemulsion electrokinetic chromatography (MEEKC) are two kinds of electrokinetic capillary chromatography (EKC), which are characterized of high solubilization capacity and separation efficiency. In our previous work, some polar organic compounds and hydrophobic neutral compounds were separated successfully by EKC1-3. In this paper, these methods were used for separating six pyridoncarboylxic acid derivatives with similar structures. T…     

胶束电动色谱分离5种二氢吡啶类钙拮抗剂

应用胶束电动毛细管色谱,以４０ｍｍｏｌ／Ｌ硼砂－４０ｍｍｏｌ／Ｌ十二烷基硫酸钠（ＳＤＳ）为运行缓冲溶液,柱温６０℃,在１３ｍｉｎ内分离了５种二氢吡啶类钙拮抗剂药物。讨论了它ＳＤＳ浓度、硼砂浓度、缓冲溶液ＰＨ、柱温对迁移时间和分离的影响。