![Quantitative SERS Detection of Uric Acid via Formation of Precise Plasmonic Nanojunctions within Aggregates of Gold Nanoparticles and Cucurbit[n]uril](/_next/image?url=https%3A%2F%2Fcloudfront.jove.com%2FCDNSource%2Fteasers%2F61682.jpg&w=3840&q=50)
Determination of nanomolar uric and ascorbic acids using enlarged gold nanoparticles modified electrode
1Department of Chemistry, Gandhigram Rural University, Dindigul, India.
Analytical Biochemistry
|December 30, 2008
Summary
This study introduces a novel electrochemical sensor for detecting uric acid (UA) and ascorbic acid (AA) at 50nM concentrations. The sensor utilizes enlarged gold nanoparticles on a modified electrode, enabling sensitive and simultaneous analysis.
Area of Science:
- Electrochemistry
- Nanomaterials Science
- Analytical Chemistry
Background:
- Accurate determination of uric acid (UA) and ascorbic acid (AA) is crucial for clinical diagnostics.
- Existing methods may lack sensitivity or the ability for simultaneous detection.
- Development of novel electrochemical sensors is needed for improved analytical performance.
Purpose of the Study:
- To develop a novel amperometric sensor for the individual and simultaneous determination of UA and AA.
- To utilize enlarged gold nanoparticles (AuNPs) self-assembled on a modified electrode surface.
- To achieve a low detection limit of 50nM for both analytes.
Main Methods:
- Fabrication of a gold electrode modified with 2,5-dimercapto-1,3,4-thiadiazole (DMT) and subsequently with citrate-stabilized gold nanoparticles (AuNPs).
- Enlargement of AuNPs using hydroxylamine seeding to create enlarged-AuNPs (E-AuNPs).
- Electrochemical characterization using cyclic voltammetry and amperometry, including electron transfer reaction (ETR) studies of [Fe(CN)(6)](3-/4-).
- Atomic force microscopy (AFM) for surface morphology analysis.
Main Results:
- Successful self-assembly of AuNPs on the Au/DMT electrode was confirmed by AFM and spectroscopic methods.
- The E-AuNPs modified electrode demonstrated significantly improved electron transfer kinetics for [Fe(CN)(6)](3-/4-) with a peak separation of 100mV.
- The E-AuNPs modified electrode effectively catalyzed the oxidation of UA and AA, achieving a voltammetric signal separation of 200mV.
- High sensitivity was achieved with a detection limit of 50nM for both UA and AA.
- The sensor was successfully applied to determine UA concentration in human blood serum and urine samples.
Conclusions:
- The developed E-AuNPs modified electrode offers a sensitive and selective platform for the simultaneous electrochemical detection of UA and AA.
- The sensor exhibits excellent catalytic activity and a low detection limit, suitable for practical applications.
- This work presents a promising approach for developing advanced electrochemical sensors for biological and clinical analysis.
