Determination of Sulphasalazine and Its Related Compounds by Simple, Smart, Validated, Green Spectrophotometric Methods

Sulphasalazine (SZ) is a prodrug. Its active metabolite (mesalazine, MZ), which is also available in pharmaceutical formulations, and the major active metabolite of MZ (N-acetyl-5-aminosalicylic acid, AS) are commonly used for the treatment of inflammatory bowel diseases.Two accurate, precise, sensitive, and specific spectrophotometric methods were developed and validated for determination of the studied components.The first method is a modified ratio difference spectrophotometric method. In this method, SZ was determined by measuring the peak area from 410-500 nm, while MZ and AS were determined by measuring the difference of the selected amplitude values. The second method is a mean centering of ratio spectra spectrophotometric method.The developed methods were linear over the concentration ranges of 2-35, 2-30 and 1-25 µg/mL for SZ, MZ and AS, respectively.The developed methods were validated according to International Conference on Harmonization guidelines. They were successfully applied for determination of studied analytes. A greenness assessment was undertaken using three different tools.Spectrophotometric methods were developed for determination of SZ and its related compounds for the first time. They were designated to be green and eco-friendly and their greenness profiles were evaluated using green solvents to keep the environment clean.