The application describes the method to determine the precise amount of triclosan in personal care products. The absorption of colored azo derivative of Triclosan is measured at a wavelength of 452 nm using a UV/VIS Excellence spectrophotometer.
How is Triclosan Determined using UV Vis Spectrophotometry?
Triclosan is commonly used in personal care products because of its antibacterial and antifungal properties. It is a stable and lipophilic compound, which is widely found in river water, lake water, sediments, fish, and even human milk. Hence, it is a concern of environmental fate. According to European Economic Community Council directive 76/768 (Annex VI) the maximum authorized concentration of triclosan in cosmetics is not more than 0.3 % (w/w).
This application is based on a derivatization experiment. First, sodium nitrite reacts with p-sulfanilic acid in an acidic medium to form a diazonium ion. Subsequently, the formed diazonium ion is added to triclosan to form a yellow-colored azo compound in an alkaline medium. The absorption of this derived yellow-colored product is measured at a wavelength of 452 nm using a METTLER TOLEDO UV/VIS Excellence spectrophotometer.