The current study focuses on the development and validation of an analytical method for quantifying cyanoacetic acid (CAA) in teriflunomide drug substance using a high-performance ion chromatography (IC) with cation suppressed conductivity detection (TFM). Water was used as the diluent for preparing the sample solution, which was injected into a standard chromatographic device with 250 mm, 4.0 mm ID, and 5.0 μm particle size Metrosep A Supp 5 Ion exchange column and a suppressed conductivity detector. At a flow rate of 0.6 mL min−1 and a temperature of 40 °C, the mobile phase was delivered in an isocratic mode. CAA and TFM had retention times of 12.78 and 15.82 min, respectively. CAA has a limit of detection (LOD) of 33 μg/g and a limit of quantification (LOQ) of 101 μg/g, respectively. For LOD and LOQ accuracy, the percentage RSD of CAA is 1.7 and 1.2, respectively. The average CAA recovery percentage was found to be between 98.6 and 100.1%. With a value of 0.9998, the calibration curve yielded an excellent linear correlation coefficient for CAA. According to the ICH guidelines, all verification parameters are within the range, indicating that the system is stable. The elution time and run time in the currently developed ion chromatography analytical method have been reduced, demonstrating that the method is cost-effective and generally accepted, as well as simple and functional, and can be used in routine quality control tests in the industry.

中文翻译：

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电导检测器离子色谱法定量测定特立氟胺原料药中氰乙酸含量

目前的研究重点是开发和验证一种使用具有阳离子抑制电导检测 (TFM) 的高效离子色谱 (IC) 对特立氟胺原料药中的氰乙酸 (CAA) 进行定量的分析方法。用水作为稀释剂制备样品溶液，将其注入具有 250 mm、4.0 mm 内径和 5.0 μm 粒径的 Metrosep A Supp 5 离子交换柱和抑制电导检测器的标准色谱设备中。在 0.6 mL min-1 的流速和 40 °C 的温度下，流动相以等度模式输送。CAA 和 TFM 的保留时间分别为 12.78 和 15.82 分钟。CAA 的检测限 (LOD) 分别为 33 μg/g，定量限 (LOQ) 分别为 101 μg/g。对于 LOD 和 LOQ 准确度，CAA 的 RSD 百分比为 1。分别为 7 和 1.2。发现平均 CAA 回收率在 98.6% 和 100.1% 之间。校准曲线的值为 0.9998，为 CAA 提供了极好的线性相关系数。根据ICH指南，所有验证参数都在范围内，表明系统是稳定的。目前开发的离子色谱分析方法的洗脱时间和运行时间有所减少，证明该方法具有成本效益和普遍接受性，并且简单实用，可用于行业的常规质量控制测试。所有验证参数均在范围内，表明系统稳定。目前开发的离子色谱分析方法的洗脱时间和运行时间有所减少，证明该方法具有成本效益和普遍接受性，并且简单实用，可用于行业的常规质量控制测试。所有验证参数均在范围内，表明系统稳定。目前开发的离子色谱分析方法的洗脱时间和运行时间有所减少，证明该方法具有成本效益和普遍接受性，并且简单实用，可用于行业的常规质量控制测试。