Lorin Marie, Delépée Raphaël, Morin Philippe, Ribet Jean-Paul
Institut de Chimie Organique et Analytique, CNRS FR 2708, UMR 6005, Université d'Orléans, BP 6759, Orléans 45067 Cedex 2, France.
Anal Chim Acta. 2007 Jun 5;592(2):139-45. doi: 10.1016/j.aca.2007.04.018. Epub 2007 Apr 19.
A rapid method for the enantiomeric purity determination of efaroxan has been developed by capillary electrophoresis (CE) using a dual cyclodextrin (CD) system. The influence of the nature and the concentration of CDs on separation parameters has been studied. High resolution (R(s)=7) and peak efficiency (104,000-121,000 theoretical plates) values were obtained for efaroxan enantiomers by adding two cyclodextrins, one neutral (7.5 mM DM-beta-CD) and the other negatively charged (3 mM CM-beta-CD) to the running buffer composed of 100 mM phosphoric acid-triethanolamine (pH 3). These resolution and peak efficiencies values allowed the quantitation of the (S)-enantiomer of efaroxan at very low enantiomeric excess even if the minor component migrates after the major one. This method was fully validated for the enantiomeric impurity determination of the (S)-form of efaroxan at the 0.05% level. Calibration curve, expressed by the peak areas ratio versus the enantiomeric purity was linear over the 0.05-1% enantiomeric impurity range (r2=0.9996). Limits of detection (LOD) and quantification (LOQ), expressed in term of (S)-enantiomer impurity were 0.02% and 0.05%, respectively. The accuracy of the method at 0.12%, 0.50% and 0.80% enantiomeric impurity levels for the (S)-form were determined. Recoveries were in 94-102% range for each quality control sample and were determined with good precision (intra-day R.S.D.=3.54%, inter-day R.S.D.=5.33%).
已开发出一种通过毛细管电泳（CE）使用双环糊精（CD）系统测定依发罗新对映体纯度的快速方法。研究了环糊精的性质和浓度对分离参数的影响。通过向由100 mM磷酸 - 三乙醇胺（pH 3）组成的运行缓冲液中加入两种环糊精，一种中性（7.5 mM二甲基-β-环糊精）和另一种带负电荷（3 mM羧甲基-β-环糊精），获得了依发罗新对映体的高分辨率（R(s)=7）和峰效率（104,000 - 121,000理论塔板数）值。即使次要成分在主要成分之后迁移，这些分辨率和峰效率值也允许在极低对映体过量情况下定量依发罗新的（S）-对映体。该方法已针对依发罗新（S）-形式的对映体杂质测定在0.05%水平进行了全面验证。以峰面积比与对映体纯度表示的校准曲线在0.05 - 1%对映体杂质范围内呈线性（r2 = 0.9996）。以（S）-对映体杂质表示的检测限（LOD）和定量限（LOQ）分别为0.02%和0.05%。测定了该方法在（S）-形式的对映体杂质水平为0.12%、0.50%和0.80%时的准确性。每个质量控制样品的回收率在94 - 102%范围内，测定精密度良好（日内相对标准偏差 = 3.54%，日间相对标准偏差 = 5.33%）。
