A QUICK VISIBLE SPECTROPHOTOMETRY APPROACH FOR THE ASSESSMENT OF MESALAZINE IN PHARMACEUTICAL PREPARATIONS

A sensitive, quick and easy visible spectrophotometry method has been developed for the determination of a widely used anti-inflammatory drug Mesalazine (MSZ) in pure form as well as in pharmaceutical preparations. In this method, oxidation of MSZ was accompanied by the reduction of Fe(III) to Fe(II) and further complexation of Fe(II) with DMG and pyridine instantly in a pH range of 6 - 8. The resultant complex was imperial red in color that could be easily seen with naked eye, spectrophotometrically showing maximum absorption at 515 nm. To achieve the maximum intensity of absorption, different variables affecting the reaction were studied and optimum conditions were established. Linear relationship was found between the absorbance and drug concentration over a range of 0.2 - 1.6 mu g/mL with a correlation coefficient (r) of 0.998. The limit of detection (LOD) and limit of quantification (LOQ) were found to be 0.769 and 2.332 mu g/mL, respectively. Statistical results obtained by the proposed method and reported methods were compared by t-test and F-test, which showed good agreement in both accuracy and precision. Spectrofluorimetric studies using the proposed method gave information about changes in the fluorescent behaviour of MSZ before and after oxidation. Cyclic voltammetry studies have also been done for understanding the electrochemical behavior of reactions involved. The proposed method has been successfully applied to the quantification of MSZ in pure form and pharmaceutical compositions.

Automated summary

A sensitive and convenient method using visible spectrophotometry was developed to determine the anti-inflammatory drug Mesalazine (MSZ) in both pure form and pharmaceutical preparations. The method involved the oxidation of MSZ along with the reduction of Fe(III) to Fe(II), followed by complexation of Fe(II) with DMG and pyridine. The resulting complex exhibited a red color that could be easily detected and had maximum absorption at 515 nm. The method showed a linear relationship between absorbance and drug concentration, with a correlation coefficient of 0.998. The proposed method was successfully applied to the quantification of MSZ in pure form and pharmaceutical compositions.