Karina Torres-Rivero Andrade

Universitat Politècnica de Catalunya, Spain

Title: Sustainable Silver and Gold Nanoparticles for the Functionalization and Electrocatalytic Enhancement of Screen Printed Electrodes

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Biography

I am Karina Torres-Rivero; currently, I am a Ph.D. student and researcher at the Universitat Politècnica de Catalunya in Barcelona, Spain. I am working with the Resource Recovery and Environmental Management (R2EM) investigation group. We are focused on developing new sensors with nanoparticle surface modifications to determine heavy metal contaminants in water. Also, we are studying the nano and microparticles utilization to remediate contaminated soils. My ultimate goal is the possibility to use the modified electrodes for heavy metal determination in acid mine drainage and extract all the available heavy metal content to synthesize chemical and green nanoparticles within the circular economy action plan.

Abstract

Screen-printed electrodes (SPEs) functionalization can enhance the electrochemical response towards specific analytes. Usually, synthesized metal nanoparticles (MNPs) employing physical and chemical strategies are used to modify SPEs but, recent developments have shown the utilization of biological reactants such as leaf, flowers, and fruits extracts in the production of MNPs. Thus, green silver (G-AgNPs) and gold nanoparticles (G-AuNPs) were synthesized employing grape stalk waste extract as a reusable organic residue from the wine industry to modify commercial screen-printed carbon nanofiber electrodes (SPCNFEs) for the determination of Pb²⁺. The G-AgNPs and G-AuNPs were characterized using scanning and transmission electron microscopy (STEM) and nanoparticle tracking analysis (NTA). The G-AgNPs and G-AuNPs were deposited onto SPCNFEs surface using spin coating technique. Also, the modified sensors G-AgNPs-SPCNFE and G-AuNPs-SPCNFE were electrochemically characterized using differential pulse anodic stripping voltammetry (DPASV) towards the determination of Pb⁺² in aqueous samples using acetic acid/acetate buffer pH 4.5. The electrochemical characterization allowed the Pb²⁺ determination with detection limits (LODs) as low as 6.9 µg.L^-1 and 6.3 µg.L^-1 using G-AgNPs-SPCNFE and G-AuNPs-SPCNFE respectively. These values are even lower than the concentration limit value established by the drinking water European legislation, 10 µg.L^- 1, making the green synthesized silver and gold nanoparticles modified electrodes a promising alternative to those sensors modified with MNPs obtained by the conventional synthesis methods.