Characterization and Application of Electrochemical Oxygen Sensors Manufactured with Gold Nanopores Decorated with Palladium

• Grant number: 23/11383-0
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• Start date: November 01, 2023
• End date: October 31, 2025
• Field of knowledge: Physical Sciences and Mathematics - Chemistry - Analytical Chemistry
• Principal Investigator: Mauro Bertotti
• Grantee: Letícia Afonso Faria
• Host Institution: Instituto de Química (IQ). Universidade de São Paulo (USP). São Paulo , SP, Brazil

Abstract

Oxygen is an element that stands out notably as the second most electronegative element on the periodic table, influencing its chemical characteristics. Moreover, because molecular oxygen is a diradical, it acts as an oxidant, engaging in various industrial and biological reactions with organic and inorganic compounds. Endogenously, the molecule produces oxidizing agents known as reactive oxygen species (ROS), which cause damage to biomolecules. Some molecules are often used as priority targets of these agents, known as suppressors, and they are crucial for minimizing harm and serving as biomarkers. Within this context, electroanalytical methods are invaluable for scrutinizing the oxygen involved in the described process due to their sensitivity, moderate cost, and portability. In the case of electrochemical sensors, the possibility of functionalizing the electrode surface in order to facilitate specific electrochemical processes can be a powerful tool to enhance the selectivity and sensibility of analytical determinations. An example is metallic nanoparticles, which favor oxygen cathodic reduction. The palladium, a prominent metal, can be utilized to facilitate and promote these reactions when combined with gold. The combination of gold, which has a high affinity for oxygen, and palladium, which has a lower affinity, can generate a more active surface than both metals, which is ideal for electrochemical reactions. In this context, the project aims to develop electrochemical sensors composed of gold nanopores coated with palladium to detect oxygen in real time during biologically relevant processes.