苯磺酸氨氯地平对映体的高效毛细管电泳手性分离

目的：建立一种快速有效拆分苯磺酸氨氯地平对映体的分析方法。方法：采用高效毛细管电泳法。以羟乙基-β-环糊精为手性选择剂对苯磺酸氨氯地平对映体进行拆分,并考察了缓冲液的pH值、手性选择剂的浓度、缓冲液浓度、电压及柱温等对分离效果的影响。结果：确定了最佳分离条件：背景电解质为含30mmol·L^-1羟乙基-β-环糊精的100mmol·L^-1磷酸-三乙醇胺（pH4．0）体系,电压为28kV,柱温为20℃,进样压力为6kPa·s,检测波长为214nm。在此条件下,10分钟内完全分离了1．0g·L^-1苯磺酸氨氯地平外消旋体,分离度为4．5,并测得3批市售苯磺酸左旋氨氯地平片的光学纯度均不低于99．6％。结论：该法可快速有效地分离苯磺酸氨氯地平对映体,可用于其手性拆分及光学纯度测定。     

毛细管区带电泳法分离盐酸吡格列酮对映体

目的建立盐酸吡格列酮对映体的毛细管区带电泳的手性分离方法。方法通过手性拆分剂的种类及浓度、缓冲液的pH及浓度、温度及电压的优化,选择合适的手性分离条件。结果选定的分离条件为40mmol·L^-1磷酸盐缓冲液（pH3．0,含6mmol·L^-1羟丙基-γ-环糊精）;检测波长为200mm;电压为18kV;温度为20℃,基线分离了盐酸吡格列酮对映体。结论本方法简便快速,可用于盐酸吡格列酮对映体的拆分。     

磺化-β-环糊精为手性选择剂拆分文拉法辛等5种碱性药物

目的以磺化-β-环糊精(S-β-CD)为手性选择剂,建立毛细管区带电泳法分离文拉法辛、奥昔布宁、维拉帕米、萘哌地尔、氟西汀对映体。方法采用未涂壁熔融石英毛细管柱,磷酸二氢钠缓冲溶液为背景电解质,分离电压为-15 kV,考察了环糊精质量浓度、缓冲溶液的pH值、缓冲盐浓度对对映体分离的影响。结果在最优的电泳条件下5种药物均达到基线分离。结论 S-β-CD是一种具有较强分离选择性的手性选择剂。     

氧氟沙星对映体的高效毛细管电泳法手性拆分

目的 建立氧氟沙星对映体高效毛细管电泳拆分的新方法.方法 以三甲基-β-环糊精(TM-β-CD)作为手性添加剂,tris-H3PO4 作背景电解质,检测波长为 282 nm,对运行缓冲溶液的pH值和浓度、TM-β-CD的浓度、分离电压、有机改性剂等因素对分离的影响进行了考察,并对拆分机制进行了初步探讨.结果 在运行缓冲液为pH2.5的75 mmol/L的tris-H3PO4溶液,30 mmol/L的TM-β-CD,操作电压为 30 kV,柱温为20℃的条件下氧氟沙星对映体达到良好分离,分离度为 3.5.结论 所建立的高效毛细管电泳方法分析时间短,重复性好,灵敏度高,适用于氧氟沙星对映体的分离.     

西布曲明对映体的毛细管电泳分离及结合常数的测定

目的 采用毛细管电泳法分离西布曲明对映体并测定其结合常数.方法 考察手性添加剂浓度、缓冲溶液pH及浓度、温度、分离电压等因素对分离度的影响,并采用双倒数法计算西布曲明对映体与2,6-二甲基-β-环糊精(DM-β-CD)的结合常数.结果 在12.5 mmol·L~(-1)DM-β-CD、100 mmol·L~(-1)Tris-H_3PO_4(pH 2.5)缓冲液、16℃柱温,30 kV操作电压的毛细管电泳条件下,西布曲明对映体在9 min内获得了良好分离,分离度达2.0;结合常数分别为154.4、173.3 L·mol~(-1).结论 所用高效毛细管电泳方法快速、准确、可靠,适用于西布曲明对映体的分离;结合常数的计算可为研究西布曲明对映体的拆分机理提供依据.     

坦洛新对映体的HS-β-环糊精的HPCE手性拆分研究

目的:建立坦洛新对映体的毛细管电泳手性拆分法。方法:10 mmol·L~(-1)HS-β-环糊精为手性添加剂,以25 mmol·L~(-1)的磷酸缓冲液,用三乙醇胺调节 pH 为3.0为背景电解质溶液,运行电压为-20 kV,毛细管温度为20℃,检测波长200nm,对坦洛新对映体进行手性分离研究,并考察了多种因素对分离的影响。结果:在该毛细管电泳条件下,坦洛新对映体能得到基线分离。结论:本方法简单、快捷、经济,可适用于坦洛新对映体分离和纯度检查。     

高效液相色谱流动相添加剂法拆分头孢氨苄对映体

目的：建立HPLC法拆分头孢氨苄对映体。方法：选用ODS Hypersil柱（4．6mm×200mm，4．5μm），以羟丙基-β-环糊精（HP-β-CD）作为手性流动相添加剂，乙腈-水（25：75）为流动相，pH为8．50，流速为0．6mL·min^-1，紫外检测波长623．8nm。考察了流动相种类、pH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头孢氨苄对映体的方法。结论：此方法简便、快速，分离度好。     

左舒必利的毛细管电泳手性分离与纯度检查

目的:建立手性分离方法并检查左舒必利光学纯度。方法:通过手性拆分剂的种类及浓度、缓冲液的pH及浓度、温度及电压的优化,选择最佳的手性分离条件。结果:最佳分离条件缓冲液为100 mmol·L~(-1)磷酸盐缓冲液(用磷酸调pH4．0,内含18 mmol·L~(-1)β-环糊精硫酸钠盐);检测波长为254 nm;电压为15 kV;温度为22℃,基线分离了舒必利2个对映体。结论:建立的毛细管电泳法可用于左舒必利的质量控制和稳定性研究。     

HPLC手性流动相添加剂法拆分马来酸氨氯地平

目的建立HPLC-手性流动相添加剂法拆分马来酸氨氯地平。方法采用C18柱考察了手性添加剂种类及浓度、水相pH值、有机改性剂比例、柱温等对马来酸氨氯地平对映体拆分分离度的影响。结果流动相为含20mmol·L^-1SBE-β-CD的10mmol·L^-1磷酸盐缓冲液-乙腈（75∶25）,pH5.0,柱温30.0℃,流速为1.0mL·min^-1时,分离度可达到2.08。结论马来酸氨氯地平对映体在C18柱上得到了基线分离。     

毛细管区带电泳法分离盐酸异丙肾上腺素对映体

目的 采用毛细管区带电泳法拆分盐酸异丙肾上腺素对映体. 方法 比较3种衍生化β-环糊精(β-CD)为手性添加剂的分离效果,对缓冲液的pH及浓度、手性添加剂的浓度、柱温、分离电压等方面进行考察及优化. 结果确定采用75 μm×75 cm未凃渍石英玻璃管柱,运行缓冲液为含50 mmol.L-1的三羟甲基氨基甲烷和40 mmol.L-1的2,6-二甲苯-β-CD的水溶液(采用磷酸调节pH至2.0),分离电压为25 kV,柱温25 ℃,检测波长为205 nm. 结论 该方法简便、快速、重复性好,在14 min内分离度可达到2.6.     

Chiral separation of oxprenolol by affinity electrokinetic chromatography-partial filling technique using human serum albumin as chiral selector

The intrinsic characteristics of capillary electrophoresis have made this technique a powerful tool in the chiral separation field. The present paper deals with the enantiomeric separation of oxprenolol enantiomers by affinity electrokinetic chromatography-partial filling technique using human serum albumin (HSA) as chiral selector. Several experimental conditions and variables affecting the separation such as pH, HSA concentration and plug length, background electrolyte concentration, temperature and voltage were studied. Baseline separation of oxprenolol enantiomers was obtained in less than 8 min under the following selected conditions: electrophoretic buffer composed of 50 mM Tris-(hydroximethyl)-aminomethane (Tris) at pH 8.5; 190 microM HSA solution applied at 50 mbar for 225 s as chiral selector; oxprenolol samples contained 190 microM HSA solution injected hydrodynamically at 30 mbar for 2s and the electrophoretic runs performed at 30 degrees C applying 15 kV voltage. The proposed methodology was applied for the analysis of two pharmaceutical preparations. Resolution, accuracy, reproducibility, speed and cost of the proposed method make it suitable for quality control of the enantiomeric composition of oxprenolol in drugs. The results show that a different affinity between oxprenolol enantiomers and HSA exists and can contribute to the pharmacokinetic differentiation of these enantiomers.     

Chiral separation of bupivacaine hydrochloride by capillary electrophoresis with high frequency conductivity detection and its application to rabbit serum and pharmaceutical injection

Conductivity detection was employed to detect the enantiomers of bupivacaine hydrochloride (Bup), which were separated by high performance capillary electrophoresis. A computer-aided technique was used to calculate the binding energies, and the interaction between Bup enantiomers and cyclodextrins (CDs) is preliminarily discussed. Factors affecting the separation efficiency such as the types and concentration of chiral selectors, running buffer, pH value, separation voltage and capillary inside diameter and length were studied. Under optimized conditions, a baseline separation of Bup enantiomers was achieved in less than 15 min in 4mM NH4Ac-NaAc-HAc (pH 4.00) -0.48mM sulfobutyl ether-beta-cyclodextrin running buffer at a separation voltage of 12 kV. The lowest detectable concentration was 0.052 microg/mL. The proposed method was applied to chiral separation of Bup enantiomers in rabbit serum and pharmaceutical injections.     

毛细管电泳测定头孢曲松钠对映体含量

目的 :建立测定头孢曲松钠对映体含量的CD毛细管电泳方法。方法 :在不同电极性的条件下 ,运用 β-环糊精 (CD)手性添加剂毛细管电泳方法 ,同时考察了背景电解质pH值及 β-CD浓度对手性拆分的影响。结果 :拆分头孢曲松钠对映体的最佳条件 :缓冲液为50mmol/Lβ-CD ,3 0mmol/L三羟甲基氨基甲烷 ,分离电压为28kV ,pH为7 15。结论 :实验结果表明 ,在优化的实验条件下 ,头孢曲松钠对映体得到了基线分离。用该方法测定不同厂家的头孢曲松钠中两种对映体的含量 ,结果表明 ,不同厂家的头孢曲松钠中对映体的含量明显不同 ,故应建立控制头孢曲松钠对映体质量的方法。该方法可为药品质量控制及临床有效选择抗菌药物提供理论依据。     

高效毛细管电泳法分离氟西汀和联苯苄唑的对映体

目的:建立拆分氟西汀和联苯苄唑两种药物手性对映体的方法。方法:采用高效毛细管电泳法,以羧甲基-β-环糊精(CM-β-CD)为手性选择剂,以未涂层熔融石英毛细管柱为分析柱,重力进样5 s,高度差10 cm,柱温20℃。分别对缓冲盐浓度、手性选择剂的浓度、缓冲盐的pH、分离电压进行考察,确定两种药物最佳分离条件;并以分离度为指标对两种药物的原料药进行分离验证试验。结果:氟西汀对映体在pH 4.5的30 mmol/LNaH2PO4缓冲溶液(含1.0%CM-β-CD)为运行电解质时达到最佳分离,分离度为3.70;联苯苄唑对映体在pH 3.0的30 mmol/LNaH2PO4缓冲溶液(含1.0%CM-β-CD)为运行电解质时达到最佳分离,分离度为5.44。方法精密度的RSD均≤0.9%(n=6)。结论:CM-β-CD的加入对氟西汀和联苯苄唑有很高的对映体选择性,可有效分离两种药物;建立的方法精密度好、经济、简便、快捷。     

多聚乙酰神经氨糖酸毛细管电泳拆分新药马来酸氨氯地平对映体及手性分离机制

目的将多聚乙酰神经氨糖酸用作分离双氢吡啶类药物对映体的毛细管电泳手性选择剂，建立新药马来酸氨氯地平对映体的拆分方法。方法考察了手性选择剂浓度、运行缓冲液pH值、毛细管温度、工作电压和多糖分子量等因素对手性分离的影响。结果马来酸氨氯地平两对映体得到了完全分离，分离度为2.20，并研究了多聚乙酰神经氨糖酸对马来酸氨氯地平的手性识别机理。结论本法操作简便，可用于该新药对映体的分离分析。     

Capillary electrochromatography for chiral separation and purity testing of pharmaceutical drug substances

Chiral separation of D,L-Norgestrel was successfully performed by cyclodextrin-modified capillary electrochromatographic (CEC) method. Optimized CEC conditions for purity testing were achieved: Hypersil C-18 packed capillary and 10 mM 2-[N-morpholino]-ethanesulfonic acid buffer (MES) and 40 v/v % methanol as background electrolyte containing 10 mM gamma-cyclodextrin at pH = 5.5. The resolution was found to be strongly dependent on the concentration of chiral selector gamma-cyclodextrin, applied voltage and temperature of the capillary. Our results represent a simple, fast and reproducible method for the separation of D,L-Norgestrel and purity testing of D-Norgestrel. It can be concluded that cyclodextrin modified HPLC, HPCE and CEC offer inexpensive, attractive and reliable chiral separation methods.     

Enantiomeric determination of ephedrine derivatives in unregulated drugs using capillary electrophoresis

Capillary electrophoresis (CE) was applied to enantiomeric separation of chiral ephedrine derivatives (d/l-ephedrine, d/l-methylephedrine, d/l-pseudoephedrine, and d/l-norephedrine) in unregulated drug products. Unregulated drugs, referred to as dietary supplements in U.S.A., have been used legally as tonic agents, but illegal substances such as ephedrine were often detected. Baseline separation of all enantiomers of ephedrine derivatives was achieved using an electrophoretic solution containing heptakis (2,6-di-O-methyl)-beta-cyclodextrin (DM-CD) as a chiral selector. The optimal conditions were established to be: capillary column of fused silica (50 microm i.d. x 56 cm); running buffer of 20 mM DM-CD with 50 mM potassium dihydrogenphosphate background electrolyte, pH 2.6; capillary temperature of 20 degrees C; applied voltage of 30 kV; on-column detection at 195 nm; and injection pressure of 50 mbar x 3 s. Under these conditions, all four pairs of enantiomers were sufficiently resolved, and eight peaks were observed with resolution factors of greater than 1.5. The calibration curves of all enantiomers showed good linearity over the concentration range of 2.5-10 microg/ml (r =0.999). The present method was used in a survey of marketed products. The resultant chiral contents were reported and the analytical data were also compared with those from HPLC. This method is useful in the simple and rapid analysis of ephedrine derivatives in marketed products.