The Effect of Antioxidants in color formation of sulfacetamide sodium eye drop under light stress

Abstract

This experiment is designed to study the effect of antioxidants, sodium metabisulfite and sodium thiosulfate, and chelating agent, disodium EDTA in color formation of sulfacetamide sodium eye drop. The results show that sodium thiosulfate can prevent the color formation better than sodium metabisulfite at every concentration used. The use of chelating agent, disodium EDTA, in combination with antioxidants show a synergistic effect of the antioxidants on color formation. However, the results indicate that the drug will be darken faster when the solution is more acidic. Phosphate buffer used for controling pH will also have an accelerated effect on the color formation of sulfacetamide sodium. It may be concluded that the most suitable formular for 10 % sulfacetamide sodium eye drop derived from this experiment should contain 0.1 % sodium thiosulfate and 0.05 % disodium EDTA. The pH of the solution is about 8.0 which is acceptable for eye drop. The use of light resistant container can reduce the rate of color formation further.