Evaluation of Pharmaceutical Quality of Mesalamine Delayed Release Tablets Using a New High Sensitivity Reversed‐Phase UPLC Method for its Genotoxic/Aniline Impurity

A reversed phase ultra performance liquid chromatography (UPLC) method was developed and validated for the quantification of aniline in mesalamine delayed‐release tablets. The optimization of the experimental condition was carried out considering some important requirements like, detection limit, short run time and reproducibility. In the present study, isocratic reversed‐phase UPLC method was developed for determination and separation of aniline from the drug product. The drug and impurity are well separated by using a reversed phase (Reprosil Gold C18‐XBD) column and mobile phase comprising of buffer pH 6.0 and acetonitrile in the ratio of 90:10 v/v. Other UPLC parameters which were optimised are flow rate, 0.5 mL/min; detection wavelength, 200 nm; column oven temperature, 50 ° C and injection volume 7 µL. Stability indicating capability was also established by forced degradation experiments. The method was validated as per ICH guideline. LOQ (limit of quantification) concentration (18 ng/mL) was found precise with RSD of less than 2%. In essence, the present study provides an improved low detection limit and lower run time for evaluation of pharmaceutical quality of mesalamine delayed‐release formulation. Moreover, the developed method was also successfully applied for quantification of aniline in mesalamine delayed‐release formulation. The same method can also be used for determination of aniline from drug substances.