Anthracene boronic acid functionalized activated screen-printed carbon electrode: A strategy for direct phosphate voltammetric detection

Phosphates (Pi) in water can be beneficial for aquatic plants and animals as they serve as a nutrient source. However, excess amounts of Pi in water can lead to eutrophication, a process that leads to excessive plant growth and oxygen depletion and, thus affects the aquatic ecosystem. Pi can also contribute to the formation of harmful algal blooms, which can produce toxins that are harmful to both humans and animals. Therefore, maintaining Pi amount within the safe range is important and through the aid of analytical tools the concentration level can be managed. Electrochemical sensors are versatile and powerful tools for environmental monitoring. We herein report a direct voltammetric sensing of Pi using a screen-printed carbon electrode functionalized with anthracene boronic acid (SPCE/ANBA). The complexation of ANBA with Pi through specific BA-Pi binding leads to the quinone formation that has been utilized for Pi detection in an electrochemical system for the first time. Under optimized conditions, the SPCE/ANBA modified electrode exhibited a wide linear range between 10 mu M and 100 mM with high selectivity and sensitivity and a detection limit of 3.2 mu M (S/N = 3). Finally, the SPCE/ANBA modified electrode was successfully tested with an environmental water sample (tap and lake) by using standard addition method. It was found that the system has satisfactory real sample results.