An electrochemical ascorbic acid sensor based on palladium nanoparticles supported on graphene oxide

Area of Science:

• Electrochemistry
• Nanomaterials Science
• Analytical Chemistry

Background:

• Ascorbic acid (AA) is a vital biomolecule with numerous health implications.
• Accurate electrochemical detection of AA is crucial for various applications.
• Existing methods often face challenges with selectivity and sensitivity.

Purpose of the Study:

• To develop a highly sensitive and selective electrochemical sensor for ascorbic acid (AA) detection.
• To utilize palladium nanoparticles supported on graphene oxide (PdNPs-GO) for enhanced electrocatalytic activity.
• To evaluate the sensor's performance in complex matrices, including vitamin C tablets.

Main Methods:

• Fabrication of a glassy carbon electrode modified with PdNPs-GO nanocomposite.
• Synthesis of PdNPs on GO sheets via a redox reaction.
• Electrochemical characterization using cyclic voltammetry and amperometry.
• Evaluation of selectivity in the presence of dopamine and uric acid.
• Determination of AA in vitamin C tablet samples.

Main Results:

• The PdNPs-GO modified electrode exhibited enhanced electrocatalytic activity for AA oxidation.
• A negative shift in anodic peak potential and a significant peak separation for AA and dopamine were observed.
• The sensor demonstrated sensitive and selective detection of AA with a rapid response time (within 5s).
• A wide linear range (20 μM to 2.28 mM) and high correlation coefficient (R=0.9991) were achieved.
• Accurate determination of AA in vitamin C tablets confirmed the sensor's practical applicability.

Conclusions:

• The PdNPs-GO modified electrode serves as a promising platform for sensitive and selective electrochemical sensing of ascorbic acid.
• The synergistic effect between PdNPs and GO enhances the sensor's performance.
• The developed sensor shows potential for practical applications in food analysis and biomedical diagnostics.