Development of Bromocresol Purple Immobilized Optical Sensor for the Determination of Dissolved Ammonia

In this work a fluorescent dye - bromocresol purple was immobilized to the xerogel prepared by the sol-gel technology. The effect of the solvent nature was explored to control the sensor properties and performance. Prepared final materials have shown stable and reproducible signals in a wide range of dissolved ammonia concentrations. Using i-butylalcohol leads to improved sensor properties because of the optimal match with the indicator dye with the immobilized environment. Developed optical ammonia sensors were investigated at different temperatures and their performance was also assessed.