An electrochemical sensor for phosphate detection in water samples

• Grant number: 22/00064-8
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• Start date: March 01, 2022
• End date: February 28, 2023
• Field of knowledge: Physical Sciences and Mathematics - Chemistry - Analytical Chemistry
• Principal Investigator: Mauro Bertotti
• Grantee: Luiz Fernando Zavatti Felipe
• Host Institution: Instituto de Química (IQ). Universidade de São Paulo (USP). São Paulo , SP, Brazil
• Associated research grant: 18/08782-1 - Miniaturized and integrated chemical sensors: new fabrication platforms for biological, clinical and environmental applications, AP.TEM

Abstract

The main goal of this project is the development of an electrochemical sensor for the detection of phosphate ions in river water samples based on a platform developed based on a nanoporous gold surface. Considering that phosphate is a non-electroactive ion, the detection will be performed indirectly by monitoring the response of the electroactive species formed between Mo(VI) and phosphate. Aiming at improving the sensitivity of the electroanalytical method, the electrodeposition parameters of the gold nanoporous film will be optimized. Scanning Electron Microscopy and X-Ray Diffraction images will be obtained to characterize the morphology of the films; hence information on the correlation between structure and electrocatalytic properties can be achieved. Since phosphate coexists with other substances in water, the sensor's selectivity will be investigated through an interference study. Determinations will be carried out in hydrodynamic conditions using a peristaltic pump and microfluidic devices to increase the analytical throughput. Calibration curves will be obtained at suitable concentration ranges, and other relevant analytical parameters such as repeatability, reproducibility, and detection limit will also be determined to evaluate the sensor performance, including real samples. (AU)