Fast and simple voltammetric sensing of avanafil in the pharmaceutical formulation by using unmodified boron-doped diamond electrode
At a Glance
Section titled âAt a Glanceâ| Metadata | Details |
|---|---|
| Publication Date | 2024-06-27 |
| Journal | ADMET & DMPK |
| Authors | Hoshyar Saadi Ali, Hemn A.H. Barzani, Yavuz Yardım |
| Institutions | Van YĂŒzĂŒncĂŒ Yıl Ăniversitesi, Lebanese French University |
| Citations | 5 |
| Analysis | Full AI Review Included |
Technical Documentation & Analysis: Unmodified BDD for Voltammetric Sensing
Section titled âTechnical Documentation & Analysis: Unmodified BDD for Voltammetric SensingâExecutive Summary
Section titled âExecutive SummaryâThis research validates the superior performance of bare, unmodified Boron-Doped Diamond (BDD) electrodes for highly sensitive electroanalytical applications, specifically the quantification of the pharmaceutical Avanafil (AVN).
- Core Achievement: Demonstrated fast, simple, and sensitive voltammetric sensing of Avanafil (AVN) using a bare BDD electrode, eliminating the need for complex, time-consuming electrode modification.
- Material Specification: The study utilized a BDD electrode with a 3 mm diameter and a precise Boron doping level of 1000 ppm.
- High Sensitivity: Achieved a low Limit of Detection (LOD) of 0.29 ”mol L-1 (0.14 ”g mL-1) using optimized Square-Wave Voltammetry (SWV).
- Robust Performance: The method exhibited a wide linear dynamic range (1.0 to 62 ”mol L-1) and high selectivity, proving unaffected by common biological and pharmaceutical interferents (e.g., metal ions, sugars, ascorbic acid).
- Practical Application: Successfully quantified AVN content in commercial pharmaceutical formulations (103.2 mg found vs. 100.0 mg labeled) and human urine samples, confirming real-world applicability.
- Mechanism Insight: The oxidation of AVN was determined to be an irreversible, diffusion-influenced process involving an approximately 1-electron, 1-proton transfer at +1.33 V (vs. Ag/AgCl).
- Value Proposition: The use of unmodified BDD simplifies the analytical process, significantly reducing resource requirements and enhancing overall feasibility compared to previous modified electrode studies.
Technical Specifications
Section titled âTechnical SpecificationsâThe following hard data points were extracted from the experimental results and optimized parameters:
| Parameter | Value | Unit | Context |
|---|---|---|---|
| Electrode Material | Boron-Doped Diamond (BDD) | N/A | Unmodified, Polycrystalline |
| Electrode Diameter | 3 | mm | Working electrode dimension |
| Boron Doping Level | 1000 | ppm | Specified BDD quality |
| Optimal Supporting Electrolyte | Britton-Robinson (BR) Buffer | 0.04 mol L-1 | Used at optimal pH 4.0 |
| Anodic Peak Potential (SWV) | +1.33 | V | vs. Ag/AgCl reference electrode |
| Limit of Detection (LOD) | 0.29 (0.14) | ”mol L-1 (”g mL-1) | Achieved via SWV |
| Limit of Quantification (LOQ) | 0.95 (0.46) | ”mol L-1 (”g mL-1) | Analytical performance metric |
| Linear Dynamic Range | 1.0 to 62 (0.5 to 30.0) | ”mol L-1 (”g mL-1) | Calibration curve correlation (r = 0.999) |
| Optimal SWV Frequency (f) | 50 | Hz | Optimized for sensitivity and selectivity |
| Optimal SWV Pulse Amplitude (âEsw) | 60 | mV | Optimized parameter |
| Optimal SWV Step Potential (âEs) | 12 | mV | Optimized parameter |
| Electron Transfer (n) | ~1.24 (Approximates 1) | N/A | Calculated based on Ep and Ep/2 |
| Tablet Recovery RSD | 3.8 | % | High precision for pharmaceutical analysis |
| Urine Sample Recovery | 92.0 ± 4.3 | % | Confirms applicability in biological matrix |
Key Methodologies
Section titled âKey MethodologiesâThe study relied on precise material handling and optimization of electrochemical parameters to achieve high sensitivity using the bare BDD surface.
- Electrode System: A standard three-electrode cell was employed, featuring the BDD working electrode, a 3 mol L-1 Ag/AgCl reference electrode, and a Pt counter electrode.
- BDD Activation Protocol: The BDD surface was pretreated daily using Anodic (APT, +1.8 V) and Cathodic (CPT, -1.8 V) cycling in 0.5 mol L-1 H2SO4 to enhance surface activity and reproducibility.
- Surface Cleaning: Between measurements, the electrode was mechanically cleaned by gentle rubbing with a moist BAS polishing pad for < 1 minute, followed by rinsing with deionized water to remove AVN oxidation byproducts.
- Electrolyte Optimization: Britton-Robinson (BR) buffer was selected as the optimal supporting electrolyte, with the pH carefully tuned to 4.0 to maximize the anodic peak current and achieve a well-defined, sharp peak.
- Voltammetric Technique Selection: Square-Wave Voltammetry (SWV) was chosen over Differential Pulse Voltammetry (DPV) due to its significantly higher sensitivity (approximately 8.6 times greater).
- SWV Parameter Optimization: Instrumental variables were fine-tuned to maximize signal intensity and minimize peak broadening, resulting in optimal settings of 50 Hz frequency, 60 mV pulse amplitude, and 12 mV step potential.
- Quantification Method: The Standard Addition Method was used for the determination of AVN in complex matrices (pharmaceutical tablets and human urine) to account for matrix effects.
6CCVD Solutions & Capabilities
Section titled â6CCVD Solutions & CapabilitiesâThis research underscores the critical role of high-quality, reproducible Boron-Doped Diamond (BDD) material in advanced electrochemistry, particularly when eliminating the need for complex surface modification. 6CCVD is uniquely positioned to supply the materials necessary to replicate, scale, and advance this work.
Applicable Materials
Section titled âApplicable MaterialsâThe research requires high-purity, electrochemically active BDD. 6CCVD recommends the following material solutions:
- Electroanalytical Grade BDD (Polycrystalline): Our standard BDD material is optimized for low background current and extended potential windows, ideal for bare electrode sensing applications like this AVN analysis.
- Custom Doping Control: The paper specified 1000 ppm B doping. 6CCVD offers precise control over boron concentration, ensuring the exact conductivity and electrochemical properties required for specific analyte oxidation mechanisms (e.g., optimizing for the observed 1-electron transfer).
Customization Potential
Section titled âCustomization Potentialâ6CCVDâs advanced MPCVD growth and fabrication capabilities directly address the needs of researchers seeking highly customized electrochemical sensors:
| Research Requirement | 6CCVD Capability | Technical Advantage |
|---|---|---|
| Electrode Dimensions | Custom plates/wafers up to 125 mm (PCD/BDD). | Allows for fabrication of large arrays or inch-size BDD wafers for high-throughput sensor manufacturing. |
| Thickness Control | SCD/PCD/BDD layers from 0.1 ”m up to 500 ”m. | Enables precise control over film properties and integration onto various substrates (up to 10 mm thick). |
| Surface Finish | Polishing to Ra < 5 nm (Inch-size PCD/BDD). | Ensures highly reproducible surface activity and minimizes adsorption effects, crucial for the âunmodifiedâ electrode approach. |
| Electrode Integration | Custom metalization services (Au, Pt, Ti, W, Cu). | We can deposit contact pads or complex electrode patterns (e.g., Ti/Pt/Au) directly onto the BDD surface for seamless integration into microfluidic or chip-based systems. |
| Patterning | High-precision laser cutting and etching. | Allows for the creation of custom electrode geometries beyond the standard 3 mm disc, such as microelectrodes or interdigitated arrays. |
Engineering Support
Section titled âEngineering SupportâThe success of this method hinges on the intrinsic quality and consistency of the BDD material. 6CCVDâs in-house PhD team specializes in diamond material science and electrochemistry. We offer expert consultation on material selection, surface termination (e.g., optimizing oxygen vs. hydrogen termination for specific analytes), and doping profiles for similar Electrochemical Sensing and Drug Analysis projects. Our support ensures that the material properties maximize sensitivity, stability, and reproducibility, fulfilling the promise of simplified, unmodified BDD sensing.
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
Background and purpose: Erectile dysfunction is a common issue among adult males involving difficulty in maintaining an erection, and it is often treated with fast-acting, low-side-effect drugs like avanafil (AVN), among other phosphodiesterase-5 inhibitors. Hence, developing fast, simple, and sensitive methods to detect AVN is crucial. Experimental approach: This study conducts an electroanalytical inquiry and provides a new voltammetric method for accurately analyzing AVN utilizing a boron-doped diamond (BDD) electrode without any modifications. Key results: In the Britton-Robinson buffer (BR, 0.04 mol L-1, pH 4.0), cyclic voltamÂmetry showed a clearly defined and irreversible anodic peak at around +1.44 V relative to Ag/AgCl. The pH of the solution was shown to have an impact on the voltammetric signals of the oxidation peaks. A good linear response for AVN quantification was achieved using square-wave voltammetry. This was done in a 0.04 mol L-1 BR (pH 4.0) solution at a potential of +1.33 V (vs. Ag/AgCl). The method exhibited a wide dynamic range of 0.5 to 30.0 ÎŒg mL-1 (1.0 to 62 ”mol L-1) and a low limit of detection of 0.14 ÎŒg mL-1 (0.29 ”mol L-1). The method proposed demonstrated suitability for determining AVN content in pharmaceutical formulations. The accuracy of the approach was demonstrated by comparing the results obtained using the developed method with those achieved using the UV-Vis spectrometry method. Conclusion: Our method simplifies the analytical process by eliminating the need for electrode modification, reducing both time and resource requirements while enhancing overall feasibility.