Enantiomeric separation of (RS)-atenolol, and (RS)-propranolol has been achieved by thin-layer chromatography (TLC) using both direct and indirect modes. (S)-naproxen, containing a carboxylic group, was utilized as the chiral selector. For direct TLC separation, (S)-naproxen was used as a chiral additive in the stationary phase in a non-covalent mode and there was no chiral additive in the mobile phase; the native enantiomers were isolated and characterized. For the indirect approach, the diastereomeric derivatives of analytes were synthesized with (S)-naproxen (as chiral derivatizing reagent) and the derivatives were then separated on achiral plates (without chiral selector); these were then isolated and characterized. The effect of the composition of the chiral selector, pH, and temperature was studied for the optimization of successful separation conditions. The developed method was validated. The limits of detection for enantiomers of atenolol and propranolol were found to be 1.2 μg mL⁻¹ and 1.6 μg mL⁻¹, respectively.

中文翻译：

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以（S）-萘普生为手性选择剂的阿替洛尔和普萘洛尔的薄层色谱对映体分离：直接和间接方法

（RS）-替诺洛尔和（RS）-普萘洛尔的对映体分离已通过使用直接和间接模式的薄层色谱法（TLC）实现。含有羧基的（S）-萘普生被用作手性选择剂。为了直接进行TLC分离，在固定相中以非共价模式将（S）-萘普生用作手性添加剂，而在流动相中则没有手性添加剂。分离和表征天然对映体。对于间接方法，分析物的非对映异构体衍生物用（S萘普生（作为手性衍生试剂），然后在非手性板上分离衍生物（无手性选择剂）；然后将其分离并鉴定。为了优化成功的分离条件，研究了手性选择剂的组成，pH和温度的影响。所开发的方法得到了验证。发现阿替洛尔和普萘洛尔对映体的检出限分别为1.2μgmL ^-1和1.6μgmL ^-1。