Thummala Veera Raghava Raju, Tharlapu Satya Sankarsana Jagan Mohan, Rekulapalli Vijay Kumar, Ivaturi Mrutyunjaya Rao, Nittala Someswara Rao
Analytical Research and Development, Integrated Product Development, Dr. Reddy's Laboratories Ltd., Bachupally, Hyderabad-500 072, India.
School of Chemistry, Andhra University, Visakhapatnam-530003, A.P., India.
Sci Pharm. 2013 Oct 21;82(1):99-115. doi: 10.3797/scipharm.1309-06. Print 2014 Jan-Mar.
A sensitive, stability-indicating gradient RP-HPLC method with PDA detection has been developed for the simultaneous analysis of drotaverine impurities in active pharmaceutical ingredient (API) and pharmaceutical formulations. Efficient chromatographic separation was achieved on an XTerra RP18, 150 × 4.6 mm, 5 μm column using gradient elution at 230 nm detection wavelength. The optimized mobile phase consisted of a 0.02 M potassium dihydrogen orthophosphate buffer of pH 3.0 as solvent A and acetonitrile as solvent B. The flow rate of the mobile phase was 1.0 mL min(-1) with a column temperature of 25°C. The method showed linearity over the range of 0.251-10.033 μg/mL, 0.231-9.995 μg/mL, 0.230-10.089 μg/mL, 0.334-10.011 μg/mL, and 0.324-10.050 μg/mL for impurities 1, 2, 3, 4, and drotaverine, respectively, with a correlation coefficient greater than 0.999. The relative retention times and relative response factors of impurities 1, 2, 3, 4 were 0.36, 0.90, 1.42, 1.55 and 1.04, 0.84, 1.10, 1.30, respectively. The drotaverine formulation sample was subjected to the stress conditions of acid, base, oxidative, thermal, humidity, and photolytic degradation. Drotaverine was found to degrade significantly in peroxide, base, and heat stress conditions. The degradation products were well-resolved from drotaverine and its impurities. The peak purity test results confirmed that the drotaverine peak was homogenous and pure in all stress samples and the mass balance was found to be more than 98%, thus proving the stability-indicating power of the method. The developed method was validated according to ICH guidelines with respect to specificity, linearity, limit of detection and quantification, accuracy, precision, and robustness.
已开发出一种采用光电二极管阵列（PDA）检测的灵敏、指示稳定性的梯度反相高效液相色谱（RP-HPLC）方法，用于同时分析活性药物成分（API）和药物制剂中的屈他维林杂质。在XTerra RP18（150×4.6 mm，5μm）色谱柱上，于230 nm检测波长下采用梯度洗脱实现了高效的色谱分离。优化后的流动相由pH值为3.0的0.02 M磷酸二氢钾缓冲液作为溶剂A和乙腈作为溶剂B组成。流动相流速为1.0 mL min⁻¹，柱温为25°C。该方法对于杂质1、2、3、4和屈他维林的线性范围分别为0.251 - 10.033 μg/mL、0.231 - 9.995 μg/mL、0.230 - 10.089 μg/mL、0.334 - 10.011 μg/mL和0.324 - 10.050 μg/mL，相关系数大于0.999。杂质1、2、3、4的相对保留时间和相对响应因子分别为0.36、0.90、1.42、1.55和1.04、0.84、1.10、1.30。屈他维林制剂样品经受了酸、碱、氧化、热、湿度和光解降解等应激条件。发现屈他维林在过氧化物、碱和热应激条件下显著降解。降解产物与屈他维林及其杂质得到了很好的分离。峰纯度测试结果证实，在所有应激样品中屈他维林峰均为均一纯峰，质量平衡大于98%，从而证明了该方法的指示稳定性能力。所开发的方法按照国际人用药品注册技术协调会（ICH）指南在特异性、线性、检测限和定量限、准确度、精密度和稳健性方面进行了验证。
