Keywords : 2
Spectrophotometric Assay of Sulphacetamide Sodium in Ophthalmic Preparation Using 2,6-Dihydroxytoluene as a New Coupling Agent
Rafidain Journal of Science,
Volume 28, Issue 3, Pages 116-127
A simple and sensitive spectrophotometric method was described for the determination of sulphacetamide sodium (SAS) in aqueous solution. The proposed method depends on diazotization of drug compound using sodium nitrite in acidic medium to produce the corresponding diazonium salt which coupled with 2,6-dihydroxytoluene reagent in presence of sodium carbonate to form a colored water soluble and stable azo-dye, which has a maximum absorption at 435 nm with a molar absorptivity and Sandalʼs sensitivity of 4.6×104 l.mol-1.cm-1 and 0.00543 µg.cm-2 respectively. Beer's law is valid over the concentration range 0.25-12.5 µg.ml-1. The relative error is in between -0.40 and +3.60 % and the relative standard deviation from ±0.13 to ±1.25 % depending on the concentration level. The proposed method was applied successfully to determine sulphacetamide sodium in its pharmaceutical formulation as ophthalmic drops.