Activated Screen-Printed Boron-Doped Diamond Electrode for Rapid and Highly Sensitive Determination of Curcumin in Food Products

At a Glance

Metadata	Details
Publication Date	2023-10-24
Journal	Materials
Authors	Jędrzej Kozak, Katarzyna Tyszczuk‐Rotko, Aleksy Keller, Magdalena Wójciak, Ireneusz Sowa
Institutions	Maria Curie-Skłodowska University, Medical University of Lublin
Citations	4
Analysis	Full AI Review Included

Technical Documentation & Analysis: Activated Boron-Doped Diamond for Curcumin Sensing

Executive Summary

This research successfully demonstrates the application of an electrochemically activated Screen-Printed Boron-Doped Diamond Electrode (aSPBDDE) for the ultra-sensitive determination of Curcumin (CCM) in food products. The findings validate the superior electrochemical properties of activated BDD materials for advanced analytical sensing.

Material Focus: Utilized Boron-Doped Diamond (BDD) in a screen-printed format, confirming BDD’s stability and wide potential window for complex organic oxidation (Curcumin).
Breakthrough Sensitivity: Achieved an extremely low Limit of Detection (LOD) of $5.0 \times 10^{<sup>-13</sup>}$ mol/L, which is 8 to 3 orders of magnitude better than most comparable analytical techniques (e.g., HPLC, Spectrophotometry).
Activation Mechanism: Electrochemical activation (5 CV scans in $0.1 \text{ mol/L NaOH}$) significantly improved sensor performance by removing organic binder, increasing surface roughness, and reducing charge transfer resistance ($R_{ct}$) from $286.5 \text{ to } 105 \text{ } \Omega \text{ cm}^{<sup>2</sup>}$.
Methodology: The procedure relies on Differential Pulse Adsorptive Stripping Voltammetry (DPAdSV), confirming that CCM electro-oxidation is controlled by adsorption onto the diamond surface.
Practical Application: The method proved highly accurate and precise for direct CCM quantification in complex matrices (turmeric extract, herbal tea, immune shots), minimizing interference through high sample dilution.
Commercial Advantage: This study establishes the aSPBDDE as the first screen-printed sensor used to quantify CCM, opening pathways for rapid, low-cost, portable food safety and quality control devices.

Technical Specifications

The following hard data points were extracted from the optimized DPAdSV procedure and material characterization:

Parameter	Value	Unit	Context
Limit of Detection (LOD)	$5.0 \times 10^{<sup>-13</sup>}$	mol/L	Optimized DPAdSV procedure
Limit of Quantification (LOQ)	$1.7 \times 10^{<sup>-12</sup>}$	mol/L	Optimized DPAdSV procedure
Primary Linear Range	$2.0 \times 10^{<sup>-12</sup>}$ to $2.0 \times 10^{<sup>-11</sup>}$	mol/L	Curcumin concentration
Supporting Electrolyte	0.025	mol/L	Phosphate-Buffered Saline (PBS)
Optimal pH	2.6	-	For maximum CCM peak current
Accumulation Potential ($E_{acc}$)	0.3	V	DPAdSV optimization
Accumulation Time ($t_{acc}$)	90	s	DPAdSV optimization
Scan Rate ($v$)	150	mV/s	DPAdSV optimization
Amplitude ($\Delta E_A$)	100	mV	DPAdSV optimization
Modulation Time ($t_m$)	10	ms	DPAdSV optimization
Charge Transfer Resistance ($R_{ct}$) Reduction	286.5 to 105	$\Omega \text{ cm}^{<sup>2</sup>}$	Result of electrochemical activation
Surface Roughness ($R_a$) Increase	0.451 to 0.517	µm	Result of electrochemical activation
Reproducibility (RSD)	3.85	%	Based on three different sensors

Key Methodologies

The experiment focused on optimizing the BDD electrode surface through electrochemical activation and fine-tuning the DPAdSV parameters for maximum sensitivity.

Electrode Material: Screen-Printed Boron-Doped Diamond Electrodes (SPBDDE) were used, consisting of a three-electrode array printed on a substrate.
Electrochemical Activation: The SPBDDE was activated (aSPBDDE) to remove organic binder and improve kinetics.
- Activation Medium: $0.1 \text{ mol/L NaOH}$ solution.
- Activation Process: Five Cyclic Voltammetric (CV) scans.
- CV Parameters: Potential range 0-2 V, Scan rate $100 \text{ mV/s}$.
Electrolyte Optimization: Phosphate-Buffered Saline (PBS) was tested across various pH levels (2.6 to 8.0) and concentrations (0.005 to $0.1 \text{ mol/L}$). Optimal conditions were found at $0.025 \text{ mol/L PBS}$ (pH 2.6).
DPAdSV Procedure: Curcumin was determined using Differential Pulse Adsorptive Stripping Voltammetry.
- Adsorption: CCM was accumulated on the aSPBDDE surface at $E_{acc} = 0.3 \text{ V}$ for $t_{acc} = 90 \text{ s}$.
- Measurement: Voltammetric curves were recorded from -0.1 to 1.2 V with a scan rate of $150 \text{ mV/s}$ and an amplitude of $100 \text{ mV}$.
Validation: Results were cross-validated against Ultra-High-Performance Liquid Chromatography coupled with Mass Spectrometry (UHPLC-ESI/MS), showing a relative error of < 8.8%.

6CCVD Solutions & Capabilities

The successful implementation of BDD in this ultra-sensitive analytical application highlights the critical role of high-quality, customizable diamond materials. 6CCVD is uniquely positioned to supply the foundational MPCVD diamond required to replicate, scale, and advance this research.

Applicable Materials

To achieve the high sensitivity and stability demonstrated in this study, researchers require high-purity, heavily doped diamond.

6CCVD Material	Description & Application	Relevance to Curcumin Sensing
Boron-Doped Diamond (BDD)	MPCVD grown polycrystalline or single crystal diamond with controlled Boron doping levels (heavy doping for metallic conductivity).	Provides the wide potential window, chemical inertness, and stability essential for highly sensitive organic electro-oxidation (CCM).
Polycrystalline Diamond (PCD)	Wafers/Plates up to 125mm in diameter, available in various thicknesses (0.1µm - 500µm).	Ideal for large-scale production of screen-printed sensors, ensuring material consistency across high-volume batches.
Custom Substrates	BDD films deposited on silicon or other substrates (up to 10mm thickness).	Allows researchers to integrate BDD directly into microfluidic or sensor platforms, bypassing the need for traditional screen-printing inks.

Customization Potential

The paper noted that electrochemical activation was necessary to remove organic binders and reduce $R_{ct}$. 6CCVD’s advanced manufacturing capabilities can provide materials that minimize or eliminate these pre-treatment steps, accelerating research and commercialization.

Custom Dimensions and Geometry: 6CCVD supplies BDD plates and wafers up to 125mm, allowing for the fabrication of large arrays of screen-printed sensors or custom-sized electrodes required for specific analytical setups. We offer precision laser cutting services to achieve unique geometries.
Surface Termination Control: We provide precise control over diamond surface termination (e.g., hydrogen or oxygen termination). By optimizing the surface before delivery, we can potentially deliver BDD with inherently lower $R_{ct}$ and higher electrochemical activity, reducing the need for aggressive post-processing activation steps.
Ultra-High Polishing: While the paper noted a roughness increase after activation, 6CCVD offers ultra-smooth polishing (Ra < 5nm for inch-size PCD). Starting with a highly controlled, smooth surface is crucial for reproducible thin-film deposition or subsequent microfabrication steps necessary for advanced sensor design.
Integrated Metalization: For miniaturized, stable three-electrode systems, 6CCVD offers in-house metalization services (Au, Pt, Ti, Pd, W, Cu). This allows for the integration of stable, on-chip reference and counter electrodes directly onto the BDD substrate, enhancing the stability and portability of the final sensor device.

Engineering Support

The successful development of this ultra-sensitive Curcumin sensor relies heavily on optimizing the diamond material properties. 6CCVD’s in-house PhD team specializes in the relationship between MPCVD growth parameters, doping density, and electrochemical performance.

We offer expert consultation to assist engineers and scientists working on similar electrochemical sensing and food analysis projects, ensuring optimal material selection for:

Achieving specific doping concentrations necessary for metallic conductivity.
Selecting the ideal crystallographic orientation (SCD vs. PCD) based on required current density and stability.
Designing custom electrode layouts and metal contacts for seamless integration into portable voltammetric analyzers.

For custom specifications or material consultation, visit 6ccvd.com or contact our engineering team directly. Global shipping (DDU default, DDP available) ensures rapid delivery of high-performance BDD materials worldwide.

View Original Abstract

Due to a great interest in the beneficial properties of polyphenolic antioxidant curcumin (CCM), sensitive and accurate methods for determining CCM are needed. The purpose of our research was to develop a very simple, fast, and sensitive differential pulse adsorptive stripping voltammetric (DPAdSV) procedure using an electrochemically activated screen-printed boron-doped diamond electrode (aSPBDDE) for the determination of CCM. The activation of the SPBDDE was accomplished in a solution of 0.1 mol/L NaOH by performing five cyclic voltammetric scans in the range of 0-2 V, at ν of 100 mV/s. The changes in surface morphology and the reduction of the charge transfer resistance due to the activation of the electrode resulted in the amplification of the CCM analytical signal on the aSPBDDE. As a result, an extremely sensitive measurement tool was formed, which under optimized conditions (0.025 mol/L PBS of pH = 2.6, Eacc of 0.3 V, tacc of 90 s, ΔEA of 100 mV, ν of 150 mV/s, and tm of 10 ms) allowed us to obtain a limit of detection (LOD) of 5.0 × 10−13 mol/L. The aSPBDDE has proven to be a highly effective tool for the direct determination of CCM in food samples with high accuracy and precision. The results are in agreement with those obtained using ultra-high-performance liquid chromatography coupled with mass spectrometry and electrospray ionization (UHPLC-ESI/MS).

Tech Support

Original Source

DOI: https://doi.org/10.3390/ma16216826

References

2022 - Electrochemical Sensor Based on Molecularly Imprinted Polymer Embedded Graphite Electrode for Detecting Curcumin [Crossref]
2023 - Determination of Curcumin on Functionalized Carbon Nano Tube Modified Electrode and Probing Its Interaction with DNA and Copper Ion [Crossref]
2020 - Poly(Glutamine) Film-Coated Carbon Nanotube Paste Electrode for the Determination of Curcumin with Vanillin: An Electroanalytical Approach [Crossref]
2020 - Low-Cost Voltammetric Sensor Based on an Anionic Surfactant Modified Carbon Nanocomposite Material for the Rapid Determination of Curcumin in Natural Food Supplement [Crossref]
2012 - Electropolymerization of Acid Chrome Blue K on Glassy Carbon Electrode for the Determination of Curcumin [Crossref]
2018 - Individual and Simultaneous Electrochemical Determination of Metanil Yellow and Curcumin on Carbon Quantum Dots Based Glassy Carbon Electrode [Crossref]
2021 - Health Benefits, Extraction and Development of Functional Foods with Curcuminoids [Crossref]
2004 - Quantitative Determination of Curcuminoids in Curcuma rhizomes and Rapid Differentiation of Curcuma domestica Val. and Curcuma xanthorrhiza Roxb. by Capillary Electrophoresis [Crossref]
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