Studying the quenching resulted from the formation of an association complex between olsalazine or sulfasalazine with acriflavine

We report the detection and quantification of important ulcerative colitis drugs olsalazine (OLS) and sulfasalazine (SUL) by the spectrofluorometric method. The proposed method was optimized and validated by using the quenching effect on the acriflavine fluorescence. The method was applied on the detection and quantification of OLS and SUL under optimized conditions showing the calibration curves were linear (range: 1.0–10.0 µg ml(−1)), with correlation coefficients R(2) of 0.9999 for both drugs. The limits of detection (LOD) and quantification (LOQ) were 53 and 104 ng ml(−1) for the OLS and 160 and 315 ng ml(−1) for the SUL. This method permitted the analysis of OLS and SUL in their pure and pharmaceutical forms. The proposed spectrofluorimetric method was also evaluated against ‘green’ criteria and all the experimental results make it an eco-friendly and safe method for the detection of OLS and SUL.