Smartphone-based colorimetric determination of triclosan in water samples after ultrasound assisted- dispersive liquid-liquid microextraction microextraction under optimized RSM conditions

Currently, use of smartphones as cost-effective, easy-to-use and portable devices for advanced colorimetric detection is emerging as a powerful analytical tool. This capability has greatly increased in recent years due to the increase in camera quality and the improvement of their electronic equipment's.In the present study, a simple and low cost methodology based on ultrasonic assisted- DLLME followed by smartphone-based colorimetric measurement was introduced for the separation and determination of TCS. This method is based on the formation of an azo compound from the alkaline reaction of TCS with a diazonium ion resulting from the reaction of sodium nitrite and p-sulfanilic acid in an acidic medium. The produced orange-yellow color is extracted in a low volume of organic phase by UA-DLLME and RGB values are recorded with Color Grab app to measure its absorbance. The effective parameters namely solution pH, concentration of p-sulfanilic acid and nitrite, reaction time and extraction solvent volume were investigated and optimized by response surface methodology (RSM) based on a BBD model. The calibration curve was linear in the range of ۵.۰ and ۳۰۰ μg L-۱ of TCS and limit of detection (LOD) was ۱.۲ μg L-۱. Then, the proposed method was successfully used for the analyses of triclosan in several environmental water and wastewater samples and satisfactory results were obtained.

Keywords:

Triclosan , Smartphone , RGB data , Ultrasound Dispersive liquid-liquid microextraction , Color Grab