Green synthesis of silver nanoparticles using five varieties of Cordyline fruticosa sp. leaves and reviewing their antimicrobial, antioxidant and photocatalytic properties
At a Glance
Section titled âAt a Glanceâ| Metadata | Details |
|---|---|
| Publication Date | 2024-05-02 |
| Journal | Brazilian Journal of Development |
| Authors | Edippuli Arachchige Dona Hiruni Amasha, Mathivathani Kandiah |
| Institutions | University of Colombo |
| Analysis | Full AI Review Included |
Technical Documentation & Analysis: Advanced Semiconductor Materials for Photocatalysis and Electrochemistry
Section titled âTechnical Documentation & Analysis: Advanced Semiconductor Materials for Photocatalysis and ElectrochemistryâExecutive Summary
Section titled âExecutive SummaryâThis research validates the potential of green-synthesized Silver Nanoparticles (AgNPs) as tunable semiconductor materials for high-value applications, particularly photocatalysis and antimicrobial treatments. This application space is directly served by 6CCVDâs advanced diamond materials, offering superior stability and performance.
- Core Achievement: Successful green synthesis of spherical AgNPs (40-50 nm) using Cordyline fruticosa extracts.
- Semiconductor Confirmation: Bandgap energy calculations (2.668-2.934 eV) confirm the semiconducting nature of the synthesized AgNPs, crucial for photocatalytic activity.
- Photocatalytic Function: Demonstrated rapid degradation of Malachite Green dye (within 5 minutes) when AgNPs were coupled with a NaBH4 catalyst.
- Biomedical Potential: AgNPs showed significant antioxidant activity and superior bactericidal effect against the gram-positive bacterium Staphylococcus aureus.
- Material Science Relevance: The reliance on semiconductor properties (bandgap tuning and electron transfer) highlights the need for robust, high-performance electrode materials, a domain where 6CCVDâs Boron-Doped Diamond (BDD) excels.
- 6CCVD Value Proposition: We provide highly stable, customizable BDD electrodes and wafers, offering enhanced chemical inertness and wider electrochemical windows compared to traditional metal nanoparticles or metal oxide catalysts for industrial scale-up.
Technical Specifications
Section titled âTechnical Specificationsâ| Parameter | Value | Unit | Context |
|---|---|---|---|
| Nanoparticle Morphology | Spherical | - | Determined via SEM analysis |
| Nanoparticle Size Range | 40-50 | nm | Observed for 4PC AgNPs |
| Bandgap Energy (Eg) Range | 2.668 - 2.934 | eV | Confirms semiconducting properties |
| Optimal Synthesis Temperature | 90 | °C | For 1CC and 4PC AgNPs |
| Optimal Synthesis Time | 45 | minutes | For 1CC and 4PC AgNPs |
| UV/Vis Absorbance Peak (SPR) | 400 | nm | Confirms AgNP synthesis |
| Highest Degradation Rate Constant (k) | 1.398 | - | Observed for 4000ppm AgNPs in photocatalysis |
| SEM Analysis Voltage | 15.0 | kV | Hitachi SU6600 SEM |
| Photocatalysis Model Dye | Malachite Green (MG) | - | Used to assess degradation efficiency |
Key Methodologies
Section titled âKey MethodologiesâThe research utilized a green synthesis approach followed by extensive chemical and physical characterization, focusing on the materialâs functional properties.
- Extract Preparation: Leaf samples were shade-dried, powdered, and extracted using distilled water (50mL per 2g powder) at 98°C for 10 minutes.
- Phytochemical Screening: Qualitative analysis confirmed the presence of key reducing agents (e.g., Flavonoids, Phenols, Tannins) responsible for Ag+ reduction and nanoparticle capping.
- AgNP Synthesis Optimization: 1mL extract was mixed with 9mL of 1mM AgNO3 solution. Optimization was performed across temperatures (60°C, 90°C, Room Temp) and time periods (15-60 minutes, 24 hours).
- Characterization:
- UV/Vis spectroscopy confirmed Surface Plasmon Resonance (SPR) peak at 400nm.
- Scanning Electron Microscopy (SEM) (Hitachi SU6600, 15.0kV) determined spherical morphology and size (40-50nm).
- Bandgap energy was calculated using the observed wavelength peak.
- Functional Assays (Antioxidant): Quantitative analysis measured Total Flavonoid Content (TFC), Total Phenolic Content (TPC), Total Antioxidant Capacity (TAC), and DPPH radical scavenging activity.
- Antimicrobial Testing: Well-diffusion technique tested AgNPs against Escherichia coli (Gram-negative) and Staphylococcus aureus (Gram-positive), compared against Gentamycin.
- Photocatalytic Activity: Degradation of Malachite Green dye was assessed under sunlight, both with AgNPs alone and with the addition of the catalyst NaBH4.
6CCVD Solutions & Capabilities
Section titled â6CCVD Solutions & CapabilitiesâThe research demonstrates the critical role of semiconductor properties in advanced environmental remediation (photocatalysis) and biomedical applications (antimicrobial activity). While AgNPs are effective, they suffer from stability issues, leaching, and limited electrochemical windows. 6CCVD offers high-purity, robust diamond materials that are ideal for replicating and scaling up these semiconductor-driven applications.
Applicable Materials
Section titled âApplicable MaterialsâTo achieve superior performance, stability, and longevity in photocatalytic and electrochemical applications, 6CCVD recommends Boron-Doped Diamond (BDD).
| 6CCVD Material | Relevance to Research Application | Key Advantage over AgNPs |
|---|---|---|
| Boron-Doped Diamond (BDD) | Photocatalysis & Electrochemistry: BDD is a highly stable, wide-bandgap semiconductor (tunable conductivity) used extensively for advanced oxidation processes (AOPs), dye degradation, and water purification. | Extreme chemical inertness, widest known electrochemical window, superior resistance to fouling and leaching, enabling high-efficiency radical generation (e.g., hydroxyl radicals). |
| Single Crystal Diamond (SCD) | High-Purity Substrates: Used for high-power electronic devices or UV sensing where the AgNPâs semiconductor function is replaced by diamondâs intrinsic properties. | Highest thermal conductivity, ultra-low defect density, ideal for high-resolution sensor integration. |
| Polycrystalline Diamond (PCD) | Large-Area Electrodes: Cost-effective alternative for large-scale water treatment or electrochemical reactors requiring high surface area BDD coatings. | Available in large formats (up to 125mm wafers), excellent mechanical robustness. |
Customization Potential for Scale-Up
Section titled âCustomization Potential for Scale-UpâThe transition from lab-scale AgNP synthesis to industrial application requires robust, structured materials. 6CCVD provides the necessary engineering solutions:
- Custom Dimensions: We supply BDD plates and wafers up to 125mm in diameter, suitable for large-scale electrochemical reactors required for industrial dye effluent treatment.
- Tunable Doping (Semiconductor Control): We offer precise control over Boron doping levels in BDD, allowing engineers to tune the materialâs conductivity and electrochemical activity (analogous to tuning the bandgap in the AgNP study) for optimal radical generation.
- Advanced Metalization: For integrating BDD electrodes into complex systems (e.g., biosensors or electrochemical cells), 6CCVD provides in-house metalization services, including Ti/Pt/Au stacks, ensuring low-resistance contacts and robust packaging.
- Surface Finish: We achieve ultra-smooth surfaces (Ra < 1nm for SCD, Ra < 5nm for PCD) crucial for minimizing non-specific adsorption in biosensing and maximizing active surface area in photocatalysis.
Engineering Support
Section titled âEngineering SupportâThe successful replication and extension of semiconductor-based photocatalysis and antimicrobial research requires deep material expertise.
- Application Expertise: 6CCVDâs in-house PhD team specializes in the electrochemical and optical properties of diamond. We can assist researchers in selecting the optimal BDD grade (e.g., heavy vs. light doping) and morphology (SCD vs. PCD) for similar Photocatalytic Degradation and Advanced Oxidation Process (AOP) projects.
- Characterization Alignment: We understand the critical role of high-resolution characterization (like the SEM analysis performed in this paper) and ensure our materials meet stringent quality control standards for purity and morphology.
For custom specifications or material consultation, visit 6ccvd.com or contact our engineering team directly.
View Original Abstract
The biological synthesis of nanoparticles using plants or microorganisms has gained attention in the recent past, mainly due to its eco-friendly nature and because they can be used in a vast variety of fields such as medicine, agriculture and textiles. The current study focuses on the green synthesis of silver nanoparticles (AgNPs) using five varieties of Cordyline fruticosa (candy cane, waihee rainbow, exotica, pink cascade and pink diamond) leaves, and assessing their antioxidant, photocatalytic and antimicrobial activities. SEM analysis of pink cascade-AgNPs shows they are spherical and in the range of 40-50nm. Band gap energy calculations reveal that synthesized AgNPs can act as semiconductors. Total flavonoid content, total phenolic content and total antioxidant capacity were analyzed and the DPPH-free radical scavenging assay was performed. These showed that AgNPs had higher antioxidant activity compared to aqueous extracts. The antibacterial activity of AgNPs and aqueous extracts was assessed using cultures of Escherichia coli and Staphylococcus aureus. Extracts and AgNPs showed better bactericidal effect on S.aureus. Photocatalytic activity of synthesized AgNPs was assessed using malachite green as a model dye and significant degradation of the dye was observed when AgNPs were added together with catalyst NaBH4. According to the results obtained from this study, it can be seen that AgNPs synthesized using Cordyline fruticosa have potential in different aspects including treatment of free-radical mediated diseases, overcoming antibiotic resistance, treatment of bacterial diseases and overcoming environmental pollution.