Effect of different modification by gold nanoparticles on the electrochemical performance of screen-printed sensors with boron-doped diamond electrode
At a Glance
Section titled âAt a Glanceâ| Metadata | Details |
|---|---|
| Publication Date | 2023-12-06 |
| Journal | Scientific Reports |
| Authors | Oleksandr Matvieiev, RenĂĄta Ć eleĆĄovskĂĄ, MariĂĄn Marton, Michal Hatala, Radovan Metelka |
| Institutions | University of Pardubice, Information Technology Institute |
| Citations | 17 |
| Analysis | Full AI Review Included |
Technical Documentation & Analysis: High-Sensitivity Dopamine Sensors using AuNP-Modified BDDE
Section titled âTechnical Documentation & Analysis: High-Sensitivity Dopamine Sensors using AuNP-Modified BDDEâExecutive Summary
Section titled âExecutive SummaryâThis research validates the critical role of Boron-Doped Diamond Electrodes (BDDE) modified with Gold Nanoparticles (AuNPs) in achieving ultra-high sensitivity for electroanalytical applications, specifically Dopamine (DA) detection.
- Performance Breakthrough: Modification of screen-printed BDDE (SP/BDDE) with AuNPs significantly enhances electrochemical performance, achieving a Limit of Detection (LOD) of 2.5 nmol L-1 for DA, substantially lower than unmodified BDDE (62.2 nmol L-1).
- Catalytic Mechanism: The catalytic effect is highly dependent on AuNP size and deposition method. The smallest physically deposited AuNPs (16.8 ± 1.7 nm) and electrochemically deposited AuNPs (eAu) yielded the best results, accelerating inner sphere redox reactions.
- Material Requirement: The study utilized highly conductive BDDE (0.017 Ω cm resistivity, 312,500 ppm B/C gas phase), confirming the necessity of Heavy Boron-Doped Diamond for high-rate electron transfer.
- Application Validation: The modified sensors were successfully applied to complex matrices, demonstrating high accuracy and repeatability (RSD < 5%) in both model solutions and spiked urine samples, ideal for Point-of-Care Testing (POCT).
- 6CCVD Value Proposition: 6CCVD specializes in providing the necessary low-resistivity, high-quality Polycrystalline Boron-Doped Diamond (PCD-BDD) wafers and custom metalization services required to replicate and scale this advanced sensor technology.
Technical Specifications
Section titled âTechnical Specificationsâ| Parameter | Value | Unit | Context |
|---|---|---|---|
| Lowest Limit of Detection (LOD) | 2.5 | nmol L-1 | Achieved by 5Au-SP/BDDE for Dopamine (DA) |
| BDDE Resistivity | 0.017 | Ω cm | Screen-Printed BDDE (SP/BDDE) |
| Boron Concentration (Gas Phase) | 312,500 | ppm | Used for CVD deposition of BDDE |
| Smallest AuNP Size (Physical Deposition) | 16.8 ± 1.7 | nm | 5Au-SP/BDDE sensor |
| AuNP Size (Electrochemical Deposition) | 21.7 ± 0.9 | nm | eAu-SP/BDDE sensor |
| Largest AuNP Size (Physical Deposition) | 317.4 ± 24.4 | nm | 50Au-SP/BDDE sensor |
| CV Scan Rate Range | 25 - 200 | mV s-1 | Used for kinetic-diffusion control analysis |
| Optimal SWV Amplitude (A) | 80 | mV | Optimized for DA determination |
| DA Determination Recovery (Urine) | 96.3 - 104.5 | % | Using eAu/SP/BDDE sensor |
| DA Determination Repeatability (RSD) | < 5 | % | Achieved in model and urine samples |
Key Methodologies
Section titled âKey MethodologiesâThe sensor fabrication and characterization involved precise CVD diamond growth and advanced nanoparticle modification techniques:
- BDDE Substrate Preparation: Chemically deposited Boron-Doped Diamond (BDDE) layer was grown onto screen-printed sensor (SPE) platforms using the Chemical Vapor Deposition (CVD) method.
- Physical Vapor Deposition (PVD) Modification:
- Au films (5 nm, 15 nm, 50 nm thicknesses) were thermally evaporated onto the BDDE surface in high vacuum.
- Subsequent annealing at 600 °C in N2 atmosphere was performed to induce dewetting, resulting in homogeneous dispersion of size-controlled AuNPs (nAu-SP/BDDE).
- Electrochemical Deposition (eAuNPs): AuNPs were electrodeposited from a HAuCl4.4H2O solution (1 mmol L-1 in 0.1 mol L-1 H2SO4) at 0 mV for 50 seconds, resulting in rougher, âstar-likeâ morphology.
- De-Alloying Method (pAuNPs): An Au/Ag bilayer was evaporated, annealed (600 °C, N2), and then wet etched in hydrofluoric acid to remove Ag, creating nanoporous AuNPs (pAu-SP/BDDE).
- Electrochemical Characterization: Cyclic Voltammetry (CV), Square Wave Voltammetry (SWV), and Electrochemical Impedance Spectroscopy (EIS) were used to evaluate electron transfer kinetics and sensitivity using outer sphere ([Ru(NH3)6]2+/3+) and inner sphere ([Fe(CN)6]4-/3-, Dopamine) redox markers.
6CCVD Solutions & Capabilities
Section titled â6CCVD Solutions & CapabilitiesâThe successful replication and commercial scaling of these high-performance BDDE sensors require precise control over diamond doping, thickness, and surface modificationâall core competencies of 6CCVD.
Applicable Materials
Section titled âApplicable MaterialsâThe research requires a highly conductive diamond layer to minimize resistance and maximize electron transfer rates, especially for inner sphere redox markers like Dopamine.
- Heavy Boron-Doped Polycrystalline Diamond (PCD-BDD): The paper utilized BDDE with a resistivity of 0.017 Ω cm, corresponding to a high boron doping level (312,500 ppm B/C gas phase). 6CCVD offers Heavy Boron-Doped PCD specifically engineered for electrochemical applications, ensuring the low resistivity and wide potential window necessary for high-sensitivity sensing.
- Custom Thickness Control: The BDDE layer thickness is critical for integration onto SPE platforms. 6CCVD provides PCD wafers with thicknesses ranging from 0.1 ”m up to 500 ”m, allowing researchers to precisely match the requirements of their screen-printed sensor architecture.
Customization Potential
Section titled âCustomization Potentialâ6CCVDâs in-house fabrication capabilities directly address the complex geometric and surface modification steps detailed in the research:
| Research Requirement | 6CCVD Capability | Benefit to Client |
|---|---|---|
| Custom Dimensions | Plates/wafers up to 125 mm (PCD) | Enables large-scale production and miniaturization of POCT devices beyond lab-scale prototypes. |
| Surface Modification (PVD) | Internal metalization services (Au, Ti, Pt, Pd, W, Cu) | 6CCVD can deposit the initial Au film layer (e.g., 5 nm, 15 nm) via PVD/E-beam evaporation, simplifying the clientâs fabrication process for subsequent annealing and AuNP formation. |
| Surface Finish | Polishing to Ra < 5 nm (Inch-size PCD) | Provides ultra-smooth baseline substrates for precise control over AuNP nucleation and morphology studies. |
| Substrate Integration | Substrates available up to 10 mm thick | Offers robust, high-quality diamond substrates for complex multi-layer sensor assemblies. |
Engineering Support
Section titled âEngineering SupportâThe successful outcome of this research hinges on optimizing the interaction between the diamond surface and the AuNPs, a process highly sensitive to the initial BDDE quality.
- Material Selection Expertise: 6CCVDâs in-house PhD team provides expert consultation on selecting the optimal BDD grade (doping level, grain size, surface termination) to maximize the catalytic effect for similar neurotransmitter detection or POCT projects.
- Process Optimization: We assist clients in defining specifications for metalization layers (e.g., Ti/Au adhesion layers) to ensure long-term stability and reproducibility, addressing the adhesion and stability challenges noted in the paper.
For custom specifications or material consultation, visit 6ccvd.com or contact our engineering team directly.