双相（O/W）识别手性萃取分离多巴对映体研究

为了研究多巴在D（L）-2酒石酸异丁酯1,2二氯乙烷有机相和羟丙基-β-环糊精水相萃取体系中的分配行为;运用双相（O/W）识别手性萃取,考察酒石酸构型和浓度、羟丙基-β-环糊精浓度、水相pH值等因素对萃取性能的影响。羟丙基-β-环糊精对S-多巴对映体的识别能力大于对R-多巴对映体的识别能力,而L-酒石酸异丁酯的识别能力刚好相反;在羟丙基-β-环糊精和L-酒石酸异丁酯萃取体系中,多巴外消旋体一次萃取分离后R和S对映体的分配系数（kR和kS）分别为8.92和5.34,分离因子α达1.67;同时pH值和萃取剂浓度对手性分离能力有显著的影响。双相（O/W）识别手性萃取具有较强的手性分离能力,它对外消旋体化合物的制备性分离有着十分重要的意义。     

非手性柱高效液相色谱法拆分盐酸西布曲明

采用非手性的Cu色谱柱,通过在流动相中加入手性选择剂β-环糊精和在样品中加入β-环糊精的方法实现对盐酸西布曲明对映体的拆分.流动相组成为含β-环糊精的甲醇-水(50∶50,V/V,pH=6).当手性选择剂β-环糊精的浓度为0.8mmol/L时,盐酸西布曲明对映体在进样后的5.7min得到了基线分离.     

羟丙哌嗪手性拆分的HPCE新方法

以组氨酸-β-环糊精（β-CD-E_2）衍生物作为手性选择剂,利用原位聚合反应制得新型β-CD衍生物手性高效毛细管电泳（HPCE）整体柱,将其应用于手性药物羟丙哌嗪的消旋体拆分。分别探究了不同缓冲体系的洗脱能力、缓冲液pH对分离的影响以及羟丙哌嗪手性拆分的线性范围。结果表明,在最佳条件下,羟丙哌嗪对映体在β-CD-E_2整体柱上能得到较好拆分,分离度Rs达到40.52,且羟丙哌嗪浓度在9.8×10~(-6)～2.0×10~(-5)mol/L范围内与对映体峰高、峰面积具有一定的线性关系。此工作将β-CD-E_2作为HPCE固定相,为手性药物羟丙哌嗪建立了一种新的分离分析体系。     

新型高效毛细管电泳手性整体柱拆分普罗帕酮

以双-(6-氧-间硝基苯磺酰基)-β-环糊精作为手性选择剂,利用原位聚合反应制得双-(6-氧-间硝基苯磺酰基)-β-环糊精手性高效毛细管电泳(HPCE)整体柱,采用HPCE法考察该柱对手性药物普罗帕酮(Propafenone)的手性拆分能力,并对其拆分条件进行优化。结果表明:在最佳条件下,普罗帕酮两对映体分离度RS达到52.82,建立了一种有效的普罗帕酮两对映体分离分析新方法。     

HPLC手性流动相添加剂法拆分盐酸美西律对映体

以羟丙基-β-环糊精(HP-β-CD)作为手性流动相添加剂,于C18柱高效液相色谱建立了盐酸美西律对映体的拆分方法.方法:本文选用ODS Hypersil柱(4.6 mm×200 mm,4.5μm),以羟丙基-β-环糊精(HP-β-CD)作为手性流动相添加剂,流动相:乙腈-水(30:70,v/v),其中含17mmol·L-1HP-β-CD.pH值为6.32,流速0.20mL·min-1;紫外检测波长:261nm;进样量:10μL.考察了流动相种类、pH值和手性流动相添加剂浓度等因素对手性拆分的影响.结果:建立了羟丙基-β-环糊精手性流动相添加剂法拆分盐酸美西律对映体的方法.结论:此方法简便、快速,分离度好.     

羧甲基聚合-β-环糊精在毛细管电泳中分离酪氨酸对映体

采用羧甲基聚合-β-环糊精为手性选择剂对酪氨酸对映体以毛细管区带电泳形式进行手性拆分。考察了手性选择剂浓度、背景电解质溶液pH值、柱温及分离电压对分离的影响。在优化的实验条件下,使酪氨酸对映得到了基线分离。     

羟丙基-β-环糊精萃取苯基琥珀酸的动力学特性

为研究β-环糊精衍生物类萃取剂萃取芳香酸对映体的动力学行为,以苯基琥珀酸对映体（PSA）为分离溶质,羟丙基-β-环糊精（HP-β-CD）为萃取剂,采用恒界面池法考察了搅拌速率、两相接触面积、萃取剂和溶质浓度等操作参数对苯基琥珀酸对映体萃取动力学的影响。实验结果表明：HP-β-CD萃取PSA为准一级反应萃取过程;且萃取发生在相界面,萃取速率随PSA的初始浓度的增大而增大,且呈线性关系。     

高效液相色谱手性流动相添加法分离氟比洛芬对映体及其分离机制

以羟丙基-β-环糊精(HP-β-CD)为手性流动相添加剂,研究了氟比洛芬对映体在反相高效液相色谱中的拆分。考察了羟丙基-β-环糊精的浓度、流动相pH值、有机调节剂、柱温对手性分离的影响,同时探讨了HP-β-CD对氟比洛芬对映体在反相高效液相中的分离机制且计算出相应的包结常数。确定了色谱条件:YMC-Pack ODS-A C18(150 mm×4.6 mm,5μm)色谱柱,流动相为0.5%乙酸(pH3.5,三乙胺调节)含25 mmol/L羟丙基-β-环糊精:甲醇(80:20,v/v),流速为1.0 mL/min,柱温为30℃,紫外检测波长为247 nm。通过容量因子(k’)的倒数1/k’对[HP-β-CD]的良好的线性关系证明氟比洛芬与HP-β-CD形成包结比为1:1包结物,(+)-氟比洛芬的包结常数为1.83 L/mol,(-)-氟比洛芬的包结常数为1.67 L/mol。     

环糊精手性流动相添加剂高效液相色谱法分离乳酸对映体的研究

分别将β-环糊精、2,6-二甲基-β-环糊精和2,3,6-三甲基-β-环糊精作为手性流动相添加剂,系统地研究了乳酸对映体在反相HPLC系统中的拆分,考察了流动相种类、pH值、流速和手性流动相添加剂的浓度对手性分离的影响,建立了甲基化β-环糊精动态手性固定相法分离乳酸对映体的方法.工作曲线的线性范围为0.02～0.18g/L(D-,L-乳酸),线性相关系数为rL-乳酸=0.9990,rD-乳酸=0.9890,精密度(n=8)为RSDLL-乳酸=0.80%,RSDD-乳酸=1.54%.     

组氨酸对映体的环糊精超分子体系手性识别研究

采用β－环糊精超分子体系对映体利用荧光分析法进行手性识别作了研究。阐明了β－环糊精对不同氨基酸对映体的手性包络作用。     

Determination of Kinetics in Biphasic Recognition Chiral Extraction for Separation of Phenylsuccinic Acid Enantiomers

This paper reports on the determination of the intrinsic kinetics in biphasic recognition chiral extraction of phenylsuccinic acid enantiomers (H₂A) by L-IBTA and HP-β-CD in a modified Lewis cell. The two-phase homogeneous reaction model was selected, because there is a finite physical solubility of phenylsuccinic acid enantiomers in both the aqueous phase and the organic phase. The regime analysis was split up in three parts: a regime analysis on the aqueous phase reaction in the absence of organic phase reaction, a regime analysis of the organic phase reaction in the absence of the aqueous phase reaction, and a regime analysis of reactions in both phases. The reactions have been found to be first order with respect to H₂A and second order with respect to L-IBTA and HP-β-CD. Competitive extraction of H₂A enantiomers with HP-β-CD and L-IBTA has great influence on the extraction process. With increase of HP-β-CD concentration, high enantioselectivity was obtained, but the extraction rate decreases.     

Reaction kinetics in reactive extraction for chiral separation of α-cyclohexyl-mandelic acid enantiomers with hydroxypropyl-β-cyclodextrin

This paper reports on determination of the intrinsic reaction kinetics in reactive extraction of α-cyclohexyl-mandelic acid (α-CHMA) enantiomers with hydroxypropyl-β-cyclodextrin (HP-β-CD) in a modified Lewis cell, in which HP-β-CD dissolved in 0.1 mol/l NaH₂PO₄/H₃PO₄ buffer solution was selected as chiral extractant. α-CHMA enantiomers were extracted from an organic phase to an aqueous phase in the extraction module. The theory of extraction accompanied by chemical reactions has been used to obtain the intrinsic kinetics of this extraction module. The different factors affecting the extraction rate, such as agitation speed, interfacial area, initial enantiomers concentration in an organic phase as well as HP-β-CD concentration in an aqueous phase were separately studied. The experimental results demonstrate that the extraction reaction kinetics is fast. The reactions between α-CHMA enantiomers and HP-β-CD in a stirred cell fall in regime 3 and are first order with respect to α-CHMA enantiomers and second order with respect to HP-β-CD with forward rate constants of 6.9×10⁻² m⁶/(mol² s) and 2.5×10⁻² m⁶/(mol² s) for S-α-CHMA and R-α-CHMA, respectively. These data will be useful in the design of the extraction process.     

固相萃取-荧光猝灭法测定氧氟沙星

在pH=7.7的Tris-HCl介质中,当加入氧氟沙星(OFLX)时,羟丙基-β-环糊精(HP-β-CD)与中性红(NR)所产生的荧光会被猝灭,对于浓度较低的实际样品采取了固相萃取前处理的方法,据此建立了固相萃取荧光猝灭法测定氧氟沙星的新方法.在优化的实验条件下,氧氟沙星工作曲线的线性范围为0.8～6.0 mg/L,回...     

Effect of 2-Hydroxypropyl-β-cyclodextrin on Solubility of Sparingly Soluble Drug Derivatives of Anthranilic Acid

Guest-host complex formation of three drug derivatives of anthranilic acid, mefenamic acid, niflumic acid, and flufenamic acid with 2-hydroxypropyl-β-cyclodextrin (2HP-β-CD) in aqueous solutions was investigated using "Phase solubility study" with UV-vis spectrophotometry. Solubility of sparingly soluble drugs has been improved by addition of 2HP-β-CD at two temperatures 298.15 K and 310.15 K and two pH values 2 and 7. The influence of different 2HP-β-CD concentration on solubility of drugs at different pH and temperatures has been investigated. The 2HP-β-CD-drug complex stability constants (K(s)), and dissociations constants (K(d)), as well as the thermodynamic parameters of reaction, i.e., the free energy change (ΔG), the enthalpy change (ΔH) and the entropy change (ΔS), were determined. The experimental data indicated formation of 1:1 inclusion complexes, which were found effective binders increasing the solubility of drugs.     

羟丙基-β-环糊精及β-环糊精与十六烷基三甲基溴化铵混合体系的电导研究

用电导法研究了十六烷基三甲基溴化铵 (CTMAB)与羟丙基 β 环糊精 (HP β CD)及 β 环糊精 (β CD)混合体系的电导行为。结果表明 ,由于CTMAB与HP β CD或 β CD间形成了包合物 ,使体系电导率增加的幅度减缓。当体系中HP β CD或 β CD的浓度增加时 ,CTMAB的临界胶束浓度 (CMC)增加 ,即转折点后移 ,且HP β CD对CTMAB的CMC转折点后移的影响较 β CD明显     

青藤碱与羟丙基-β-环糊精的包合作用

通过溶液共混法制备青藤碱-羟丙基-β-环糊精包合物,纯化后利用体视显微镜观察包合物的结晶形态,通过差热示重扫描、红外光谱、X射线粉末衍射及核磁共振波谱等方法对包合物进行性质分析,并通过相溶解度法计算包合物的包合常数。结果表明,青藤碱、羟丙基-β-环糊精包合后性质发生明显变化,羟丙基-β-环糊精能显著增加青藤碱的溶解度,包合物中青藤碱与羟丙基-β-环糊精包合分子个数比为1∶1,其包合常数为150.0 L/mol,反应的吉布斯自由能为-12.41 kJ/mol。     

毛细管电泳测定手性邻氯扁桃酸及在拆分微生物筛选中的应用

为用微生物法拆分邻氯扁桃酸对映体,建立了用毛细管电泳检测邻氯扁桃酸对映体的方法。毛细管电泳分离最佳条件为100 mmol.L-1硼酸缓冲液,110 mmol.L-1羟丙基-β-环糊精,pH=8.0,温度25℃,分离电压18kV。用该方法对来源于土壤、食堂油污、炼焦厂工业废水的210种细菌、霉菌和酵母进行了筛选,其中在土壤中筛选得到1株水解混旋邻氯扁桃酸甲酯生成R(-)-邻氯扁桃酸的细菌菌株,其水解活性高,ee值达91%。     

HP-β-CD对依达拉奉的增溶研究

采用相溶解度法探讨羟丙基-β-环糊精(HP-β-CD)对依达拉奉的增溶作用。在水溶液中,依达拉奉的浓度随HP-β-CD浓度的增加而呈线性增加,相溶解度曲线为AL型。经HP-β-CD包合后依达拉奉在水中的溶解度最高可达包合前的5.026倍,包合物的稳定常数Kc=10.31。