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1.
用β-环糊精(β-CD)和去氧胆酸钠(SDC)的环糊精改性毛细管胶束电动色谱,实际拆分了EMD-56431和扑尔敏两种手性药物,研究了SDC和β-CD浓度及pH值对分离的影响。初步讨论了分离的机理。认为CD-SDC体系中胶束单体分子几乎均被CD包合;CD可能与部分胶束单体包合而存在于SDC的胶束中;该拆分体系中SDC与β-CD的浓度比在4∶1~4∶3时拆分效果最好。并发现SDC对β-CD有显著的增溶作用。  相似文献   

2.
陆豪杰  阮宗琴  李菊白  欧庆瑜 《分析化学》2000,28(12):1567-1567
1引言环糊精及其电中性衍生物(二甲基-β-环糊精(DM-β-CD)、三甲基-β-环糊精(TM-β-CD)、羟丙基-β-环糊精(HP-β-CD))是毛细管电泳(HPCE)手性分离中最常采用的手性选择剂,带电环糊精是HPCE手性分离中另一类重要的手性选择剂,它的带电性质使其在手性拆分过程中起到非常重要的作用。本文分别考察了带电的磺丁基-β-环糊精(SBB-β-CD)与电中性的DM-β-CD、TM-β-CD以及HP-β-CD等3种双环糊精体系的手性拆分性能,研究了双环糊精在手性分离中所体现出的协同效应…  相似文献   

3.
李益民  戚文彬 《分析化学》1994,22(6):548-551
本文从β-环糊精(β-CD)的包合作用及其对表面活性剂(SF)包合后引起的包合常数增大等方面,探讨了β-CD-与离子表面活性剂对显色反应的协同增敏作用机理,研究表明:β-CD与SF形成包合物SF-β-CD及SF-β-CD对显色剂及其显色络合物包合作用的增强,是产生协同增敏作用的主要因素,但还须考虑对空白值的影响以及配合物的稳定性,还提出了对一同显色体系应用不同SF-β-CD估计协同增敏趋势的方法。  相似文献   

4.
本文以β-环糊精(β-CD)和表面活性剂为增效试剂,分别研究了它们对以Fe-meso-(四(4-磺基苯)卟啉)(Fe-TPPS4)为催化剂,催化过氧化氢氧化4-氨基安替比林(4-AAP)与苯酚衍生物显色反应的速度和灵敏度的影响,发现β-CD和十二烷基苯磺酸钠(SDBS)对该体系具有明显的增效作用.在3×10-3mol/Lβ-CD存在下,测定H2O2的灵敏度比文献报道的提高了1.56倍.利用SDBS浓度与催化显色反应初速度的增加值之间的线性关系,建立了测定微量SDBS的方法  相似文献   

5.
研究了CD-SDS胶束电动色谱(CD-MEKC)对电中性及疏水性的手性化合物的分离,并讨论了不同类型CD的手性识别作用。使用γ-CD可以有效地拆分十八甲基块诺酮(NOG)旋光异构体。选择了最佳分离条件,通过调节CD和SDS浓度以及其它操作条件可以把NOG异构体很好的分离。  相似文献   

6.
刘玉  顾俊岭  傅若农  王晓霞 《色谱》1995,13(5):387-389
 研究了CD-SDS胶束电动色谱(CD-MEKC)对电中性及疏水性的手性化合物的分离,并讨论了不同类型CD的手性识别作用。使用γ-CD可以有效地拆分十八甲基块诺酮(NOG)旋光异构体。选择了最佳分离条件,通过调节CD和SDS浓度以及其它操作条件可以把NOG异构体很好的分离。  相似文献   

7.
苏小笛  朱敏 《应用化学》1997,14(3):33-36
本以β-环糊精(β-CD)和表面活性剂为增效剂,分别研究了它们对以Fe-meso-(四(4-磺基苯)卟啉)(Fe-TPPS4)为催化剂,催化过氧化氢氧化4-氨基安替比林(4-AAP)与苯酚衍生物显色反应的速度和灵敏度的影响,发现β-CD和十二烷基苯磺酸钠(SDBS)对该体系具有明显的增效作用,在3×10^-3mol/Lβ-CD存在下,测定H2O的灵敏度比献报道的提高了1.56倍,利用SDBS深  相似文献   

8.
张书胜  梁丽  袁倬斌 《色谱》1999,17(1):52-54
在玻碳纤维微电极上研究了电解液中β-环糊精(CD)的浓度对邻、间、对苯二酚的循环伏安特性的影响,从实验结果和分子结构水平方面考察了β-CD与邻、间、对苯二酚的包结作用。研究结果表明,β-CD与邻、间、对苯二酚的包结作用强弱顺序为间苯二酚、邻苯二酚、对苯二酚。讨论了电泳缓冲液中ΝΗ4Cl,SDS,β-CD的浓度及pH值对邻、间、对苯二酚迁移时间的影响。建立了苯二酚异构体胶束电动毛细管色谱-玻碳微电极柱上安培检测分析方法,方法的回收率在98%~103%之间。  相似文献   

9.
阮宗琴  康经武  欧庆瑜 《色谱》1998,16(6):481-484
分别测定了毛细管区带电泳环糊精手性拆分体系中α,β-环糊精和二甲基、三甲基、羟丙基-β-环糊精与药物对映体特布他林形成包结络合物的稳定常数以及手性拆分过程的热力学函数的变化。数据分析表明,环糊精稳定常数的大小反映了环糊精空腔与分离对象之间的匹配程度。环糊精稳定常数的相对值反映了手性拆分体系的分离能力。两对映体与环糊精所形成包结络合物的Δ(ΔH)和Δ(ΔS)分别反映了手性拆分过程中立体作用与构象匹配的差异。与甲基化β-环糊精相比,羟丙基-β-环糊精和β-环糊精提供的氢键作用在手性拆分中起着重要作用。  相似文献   

10.
疏水条件下甾体化合物的分离及环糊精的作用   总被引:2,自引:0,他引:2  
分别应用胶束电动毛细管色谱法(MECC)、反相色谱法和串联柱HPLC法分离 左旋十八甲基炔诺酮(LNG)、睾酮(T)、孕酮(P-雌二醇(E2)等甾体化合物MECC分离在未涂层毛细管柱上进行。当电泳缓冲溶液为含20mmol/L的2,6-二甲基-β环糊精((DM-β-CD)添加剂和50mmol/L的十二烷基硫酸钠(SDS)的10mmo/L四硼酸钠(PH9.2)时,可实现快速分离。通过与反相色谱法和串联  相似文献   

11.
A cyclodextrin-modified micellar capillary electrophoretic method (MECC) was developed using mixtures of beta, cyclodextrins (beta-CD) and mono-3-O-phenylcarbamoyl-beta-CD as chiral additives for the chiral separation of miconazole with the dual CDs systems. The enantiomers were resolved using a running buffer of 50 mmol/L borate pH 9.5 containing 15 mmol/L beta-CD and 15 mmol/L mono-3-O-phenylcarbamoyl-beta-CD containing 50 mmol/L sodium dodecyl sulfate and 1 mol/L urea. A study of the respective influence of the beta-CD and the mono-3-O-phenylcarbamoyl-beta-CD concentration was performed to determine the optimal conditions with respect to the resolution. Good repeatability of the method was obtained.  相似文献   

12.
程燕  白敏  王新梅  明永飞  尤进茂 《色谱》2006,24(2):188-191
以咔唑-9-乙基氯甲酸酯(CEOC)作为柱前衍生试剂,采用毛细管电泳对14种二肽进行了手性拆分。以5种二肽为代表,考察了缓冲液种类、浓度、pH值、二元手性选择剂的组合配比等因素对二肽的拆分效果,优化了实验条件。在各自的优化条件下,14种二肽手性拆分的分离度均在3.63以上,最高分离度可达43.14(Gly-Ala)。  相似文献   

13.
姚彤炜  曾苏  丁海青 《色谱》1997,15(4):316-318
以β-CD为手性流动相添加剂、苯巴比妥为内标,于FLC-C8反相柱上建立了鼠肝微粒体中5-(对-羟基苯基)-5-苯基乙内酰脲(p-HPPH)外消旋体的拆分方法。测得p-HPPH对映体的线性范围为0.5~110mg/L(r=0.9996);最低检出量为5ng(S/N=3);S-p-HPPH的回收率为93.6%±2.8%,R-p-HPPH的回收率为94.7%±1.8%;日内和日间精密度RSD值均小于2%。所建立的方法具有结果准确、操作方便等特点。  相似文献   

14.
The chiral separation of simendan enantiomers using capillary electrophoresis was studied with beta-cyclodextrin (beta-CD) as chiral selector. The influences of the concentration and pH of borate buffer solution, beta-CD concentration and methanol content in the background electrolyte were investigated. These factors were compared with those in an HPLC with beta-CD as chiral mobile phase additive (CMPA-HPLC). The quantification properties of the developed CE method were examined. A baseline separation of simendan enantiomers was achieved in the background electrolyte of 20 mmol/L borate buffer (pH 11.0) containing 12 mmol/L beta-CD-methanol (50:50 in volume ratio). The CE method is comparable with CMPA-HPLC in chiral resolution, although the optimal pH in CE (11.0) is much higher than that (6.0) in CMPA-HPLC. This chiral CE method is applicable to the quantitative ananlysis and enantiomeric excess value determination of L-simendan.  相似文献   

15.
An efficient micellar electrokinetic capillary chromatography method was developed to analyze three major active components including morroniside, loganin and gallic acid in Fructus corni and its six preparations for the first time. The factors that could affect the separation were studied, such as the pH of the buffer, concentrations of SDS, organic modifier and beta-CD, and the applied voltage. The optimum analysis conditions were 10 mmol/L NaH(2)PO(4)-5 mmol/L Na(2)B(4)O(7) (pH 6.8) buffer containing 140 mmol/L SDS, 1 mmol/L beta-CD, 5% (v/v) methanol and 12.5 kV applied voltage. The linearity between the peak-areas and the concentrations of the analytes were investigated, and they exhibit excellent linear behavior over the concentration ranges (correlation coefficients 0.9953-0.9995). In addition, the pK(a) of gallic acid was determined using capillary zone electrophoresis. The result was consistent with that reported by the literature.  相似文献   

16.
A new beta-cyclodextrin (beta-CD) derivative, 2-O-(2-hydroxybutyl)-beta-CD (HB-beta-CD), was successfully synthesized and used as chiral selector in capillary zone electrophoresis. Six chiral drugs, such as anisodamine, ketoconazole, propranolol, promethazine, adrenaline and chlorphenamine enantiomers, belonging to different classes of compounds of pharmaceutical interest were resolved. The chiral resolution (R(S)) was strongly influenced by the concentrations of the cyclodextrin derivative, the background electrolyte, and the pH of the background electrolyte. Under the conditions of 50 mmol/L tris-phosphate buffer at pH 2.5 containing 5 mmol/L 2-O-(2-hydroxybutyl)-beta-CD, the baseline separation of enantiomers, such as anisodamine (R(S) = 3.10), ketoconazole (R(S) = 3.01), propranolol (R(S) = 3.87), promethazine (R(S) = 3.63), adrenaline (R(S) = 3.42) and chlorphenamine (R(S) = 2.96), could be achieved.  相似文献   

17.
 采用 5种环糊精衍生物对碱性药物硫喷妥钠、盐酸氟桂利嗪、山梗菜碱进行了毛细管区带电泳的手性拆分。结果表明 ,采用含 2 % (质量分数 ,其余相同 )聚合 β 环糊精 (P β CD)或 0 5%羧甲基聚合 β 环糊精 (CM P β CD) 30mmol/L的Tris H3PO4缓冲液可使这 3种药物达到基线分离 ;使用CM P β CD时 ,分离度高达 4~35。  相似文献   

18.
毛细管电泳分离与测定尿液中扑尔敏对映体   总被引:2,自引:0,他引:2  
以HP-β-CD作为手性分离添加剂,对标样和实际尿液中的扑尔敏进行了手性分离和测定研究。在实际样品的分离测定时,用液液萃取时间样品预处理,并采用电堆集进样以提高检测灵敏度,对于尿液中扑尔敏对映体的检测限为1.5×10^-7g/L。  相似文献   

19.
In this study, enantioseparations of five phenothiazines in cyclodextrin (CD)-modified micellar electrokinetic chromatography (MEKC) were investigated using a citrate buffer containing tetradecyltrimethylammonium bromide (TTAB) as a cationic surfactant at low pH. Beta-cyclodextrin (beta-CD) and hydroxylpropyl-beta-CD (HP-beta-CD) were selected as chiral selectors. The results indicate that the separation window is greatly enlarged by beta-CD concentration and that the separability and selectivity of phenothiazines are remarkably influenced by the concentrations of both beta-CD and TTAB, as well as buffer pH. The interaction of thioridazine with beta-CDs is considerably reduced in the presence of TTAB micelles due to competitive complexation of thioridazine with TTAB micelles, which is pH-dependent. As a result, effective enantioseparation of thioridazine is simultaneously achievable with that of trimeprazine and promethazine or ethopropazine in MEKC with addition of either beta-CD or HP-beta-CD, respectively, to a micellar citrate buffer containing TTAB at pH 3.5. Better enantioresolution of thioridazine in MEKC than in capillary zone electrophoresis can be obtained.  相似文献   

20.
成禹杉  杨晓兰  余瑜 《色谱》2007,25(4):478-481
建立了毛细管电泳手性分离多沙唑嗪中间体对映体的方法,并同时分离了多沙唑嗪对映体。考察了不同种类季铵盐对电渗流及分离的影响,其中四甲基氢氧化铵(TMB)能有效控制电渗流并提高组分的分离度。实验还考察了其他因素,如pH值、分离电压和磷酸二氢钠浓度对分离的影响。所用的毛细管为40 cm(有效长度30 cm)×50 μm,缓冲液为12 mmol/L β-环糊精、30 mmol/L TMB、60 mmol/L 磷酸二氢钠(pH 2.2),分离电压为20 kV。在此条件下多沙唑嗪及其中间体的对映体均达到了基线分离。实验结果表明,一些用β-环糊精不能完全分离的对映体通过加入TMB控制电渗流能达到满意的分离效果。  相似文献   

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