In the present work, the fabrication of an optode for determination of low levels of mercury is described in which the sensing reagent is dithizone immobilized on triacetylcellulose membrane. Also a simple method is presented for immobilizing reagent on membrane. The reaction takes place within few minutes and a color change occurs from green to red, which is spectroscopically detected in the absorbance mode.
Contrary to the previous work [10], we did not observe any drift of signal upon exposure to light during measurements.