Allergan Pharmaceuticals, Westport, Mayo, Ireland; Irish Separation Science Cluster (ISSC), National Centre for Sensor Research, Dublin City University, Glasnevin, Dublin 9, Ireland.
Pharmaceutical and Molecular Biotechnology Research Centre (PMBRC), Department of Chemical and Life Sciences, Waterford Institute of Technology, Waterford, Ireland.
J Chromatogr A. 2014 Jan 17;1325:213-20. doi: 10.1016/j.chroma.2013.12.011. Epub 2013 Dec 14.
An enantioselective supercritical fluid chromatography (SFC) method was developed and validated to meet the current European Pharmacopoeia requirements of a limit test for the determination of S-timolol maleate enantiomeric purity in timolol maleate drug substance. The developed method is presented as an alternative to the current normal phase high performance liquid chromatography (NP-HPLC) method described in the European Pharmacopoeia (Timolol Maleate Monograph). Using a 4.6mm×250mm Chiralcel OD-H (dp: 5μm) column and a mobile phase of (93:7) CO2/0.1% (v/v) TEA in MeOH delivered at 4.0mLmin(-1) resolution of 2.0 was achieved within 5min, representing a 3-fold reduction in run-time and an 11-fold reduction in solvent consumption relative to the NP-HPLC method. Method robustness was examined by the variation of flow rate (±0.5mLmin(-1)), column temperature (±5°C) and column back-pressure (±10bar) and resolution was maintained at ≥1.9 in all cases. R-timolol was resolved from all potential impurities and the limit of detection was improved by increasing the sample concentration threefold compared to the NP-HPLC method such that the method could detect the R-timolol enantiomer at 0.5% (w/w) with respect to S-timolol maleate. Additional validation parameters demonstrated that the potential of the method to be used for routine release testing of timolol maleate raw material for drug product manufacturing in which the quantitation of R-timolol impurity in S-timolol maleate drug substance would be a requirement.
建立并验证了一种对映体选择性超临界流体色谱（SFC）方法，以满足当前欧洲药典中马来酸噻吗洛尔原料药中 S-噻吗洛尔马来酸盐对映体纯度限度检测的要求。该方法可替代欧洲药典（马来酸噻吗洛尔专论）中现行的正相高效液相色谱（NP-HPLC）方法。采用 4.6mm×250mm Chiralcel OD-H（dp：5μm）柱，以（93：7）CO2/0.1%（v/v）TEA 在 MeOH 中的流动相在 4.0mLmin-1 的流速下，5min 内实现了 2.0 的分辨率，与 NP-HPLC 方法相比，运行时间缩短了 3 倍，溶剂消耗减少了 11 倍。通过改变流速（±0.5mLmin-1）、柱温（±5°C）和柱背压（±10bar）考察了方法的稳健性，在所有情况下分辨率均保持在≥1.9。R-噻吗洛尔与所有潜在杂质得以分离，与 NP-HPLC 方法相比，通过将样品浓度提高三倍，检测限得以提高，使得该方法能够检测到马来酸噻吗洛尔原料药中 R-噻吗洛尔对映体的含量为 0.5%（w/w）。其他验证参数表明，该方法有望用于马来酸噻吗洛尔原料药的常规放行检测，在马来酸噻吗洛尔原料药中需要定量检测 S-噻吗洛尔马来酸盐中的 R-噻吗洛尔杂质。
