Synthesis of ultrasmall cerium oxide nanoparticles in deep eutectic solvent and their application in an electrochemical sensor to detect dopamine in biological fluid

Author(s)

Gomes-Junior, Paulo Cardoso ; Longatto, Gustavo Patelli ; Augusto, Karen Kenlderi de Lima ; Rocha, Josias da Silveira ; Piccin, Evandro ; Fatibello-Filho, Orlando

• Document type: Journal article
• Source: Microchimica Acta; v. 191, n. 7, p. 12-pg., 2024-07-01.

Abstract

A solvothermal synthesis of ultrasmall cerium oxide nanoparticles (USCeOxNPs) with an average size of 0.73 +/- 0.07 nm using deep eutectic solvent (DES) as a stabilizing medium at a temperature of 90 degrees C is reported. Transmission electron microscopy (TEM) and energy dispersive spectroscopy (EDS) were used to morphologically characterize the USCeOxNPs. These revealed approximately spherical shapes with emission lines characteristic of cerium. Selected area electron diffraction (SAED) was used to determine the crystalline structure of the cerium oxide nanoparticles (CeO2NPs), revealing the presence of crystalline cubic structures. The USCeOxNPs-DES/CB film was characterized by scanning electron microscopy (SEM), which demonstrated the spherical characteristic of CB with layers slightly covered by DES residues. DES was characterized by Fourier transform infrared (FT-IR) and nuclear magnetic resonance (NMR), indicating its formation through hydrogen bonds between the precursors. An electrochemical sensor for dopamine (DA) determination in biological fluids was developed using the USCeOxNPs together with carbon black (CB). An enhanced current response was observed on DA voltammetric determination, and this can be attributed to the USCeOxNPs. This sensor displayed linear responses for DA in the range 5.0 x 10-7 mol L-1 to 3.2 x 10-4 mol L-1, with a limit of detection of 80 nmol L-1. Besides detectability, excellent performances were verified for repeatability and anti-interference. The sensor based on USCeOxNPs synthesized in DES in a simpler and environmentally friendly way was successfully applied to determine DA in biological matrix. (AU)

• FAPESP's process: 22/15513-2 - Development of electrochemical sensors based on carbonic material and metallic nanoparticles synthesized in deep eutectic solvents for the determination of emerging contaminants
• Grantee: Gustavo Patelli Longatto
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• FAPESP's process: 19/22217-8 - Thermoanalytical studies applied to antihepatitis and antiretroviral drugs of the protease inhibitor class: thermal behavior, decomposition intermediates, volatile characterization and polymorphism
• Grantee: Éder Tadeu Gomes Cavalheiro
• Support Opportunities: Regular Research Grants
• FAPESP's process: 24/04116-8 - Use of deep eutectic solvents in sustainable spectrophotometric and electroanalytical procedures
• Grantee: Orlando Fatibello Filho
• Support Opportunities: Regular Research Grants