This paper deals with chromatographic method development for the simultaneous estimation of levocetrizine hydrochloride and montelukast sodium in their combined dosage form using analytical quality by design approach. The main objective for application of analytical quality by design approach was to identify conditions where an adequate separation could be achieved within a robust region. Critical method parameters that have the most influence on resolution and retardation factors of both drugs are volume of methanol and volume of modifier (triethylamine); these critical parameters were screened by using Taguchi orthogonal array (OA) design from the seven potential method parameters. Further 3² factorial design was used for establishing the relationship between critical process parameters: volume of methanol and volume of modifier (triethylamine) on critical quality attributes: resolution and retardation factors of both drugs. The chromatographic separation was performed using aluminium backed pre-coated silica gel 60 F₂₅₄ as stationary phase and ethyl acetate:methanol:triethylamine (5:5:0.04, % v/v) as the mobile phase. The quantification was carried out at 234 nm wavelength. The Rf values were found to be 0.23 ± 0.02 and 0.55 ± 0.02 for levocetrizine hydrochloride and montelukast sodium, respectively. The method was validated as per ICH Q2(R1) guidelines where the method was found to be specific, linear, precise, robust and accurate in the range of 100–500 ng/band for levocetrizine hydrochloride and 200–1000 ng/band for montelukast sodium. The developed HPTLC method was successfully applied for the routine analysis of levocetrizine hydrochloride and montelukast sodium in their combined tablet dosage form.

中文翻译：

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设计方法中的分析质量在方法开发中同时评估左旋西替利嗪盐酸盐和孟鲁司特钠的剂型

本文旨在通过设计方法，利用分析质量，同时测定左西替利嗪盐酸盐和孟鲁司特钠组合剂型的色谱方法开发。通过设计方法应用分析质量的主要目的是确定可以在稳健区域内实现充分分离的条件。对两种药物的分离度和阻滞因子影响最大的关键方法参数是甲醇量和改性剂（三乙胺）量。通过使用Taguchi正交阵列（OA）设计从七个潜在方法参数中筛选出这些关键参数。再3 ²析因设计用于建立关键工艺参数：甲醇量和改性剂（三乙胺）量之间的关系，其关键质量属性为：两种药物的分辨率和阻滞因子。色谱分离使用铝支持的预涂硅胶60 F ₂₅₄作为固定相和乙酸乙酯：甲醇：三乙胺（5：5：0.04，％v / v）作为流动相。定量在234nm波长下进行。盐酸左西替利嗪和孟鲁司特钠的Rf值分别为0.23±0.02和0.55±0.02。该方法已按照ICH Q2（R1）指南进行了验证，发现该方法具有特异性，线性，精确，稳健和准确度，盐酸左西替利嗪为100-500 ng / band，孟鲁司特为200-1000 ng / band。钠。所开发的HPTLC方法已成功地用于盐酸左西替利嗪和孟鲁司特钠的组合片剂剂型的常规分析。