NS4 - Dual Plant Mediated Ag-TiO₂ Nanocomposites Antimicrobial and Photocatalytic Applications
SCURS Disciplines
Biochemistry
Document Type
General Presentation (Oral)
Invited Presentation Choice
Not Applicable
Abstract
Antimicrobial resistance and persistent pharmaceutical contaminants continue to threaten aquatic ecosystems and public health, creating an urgent need for sustainable and multifunctional remediation strategies. In this work, green-synthesized silver-doped titanium dioxide (Ag-TiO₂) nanocomposites were developed using silver-doping to decrease the band gap of TiO₂ for the nanoparticle to utilize a broader spectrum of low UV and high visible light waves. Moringa oleifera leaf extract is harnessed as a natural reducing and stabilizing agent, followed by photosensitization with Clitoria ternatea (butterfly pea) flower extract for enhanced antimicrobial and photodegradation activity. This phytomediated synthesis minimizes harsh chemical inputs while promoting enhanced light absorption and antimicrobial functionality.
Silver-doped titanium dioxide (Ag-TiO₂) nanocomposites were synthesized via a phytomediated approach. Titanium propoxide (TPP) and isopropanol were used as the primary reactants, while Moringa oleifera leaf extract served as a natural reducing and stabilizing agent. A silver nitrate solution was added, and the solution was mixed for 6 hrs at 85 ºC. The precipitate was dried for 3 hr at 110 ºC and calcinated at 400 ºC. The resulting nanocomposites were photosensitized with Butterfly Pea Flower extract by soaking the nanocomposites in the extract in the dark for 24 hr. FTIR, pXRD, and UV-Vis were used to characterize the nanocomposites. To test the antimicrobial properties colony-forming unit (CFU), optical density (OD), and Kirby-Bauer disk diffusion tests were completed against gram-negative and gram-positive bacterial controls. β-blocker pharmaceutical waste models, atenolol and propranolol, were used to test the nanocomposites' ability to degrade harmful toxins in water treatment while exposed to UV radiation for 2 hrs and measuring the degradation of pharmaceutical wastes using UV-Vis.
Antimicrobial activity was evaluated against gram-negative and gram-positive bacteria using CFU, OD, and Kirby-Bauer disk diffusion assays. The 5% Ag-TiO₂ nanocomposite achieved 88.3% inhibition of E. Coli K-12 and 89.5% inhibition of E. Coli B, demonstrating strong antibacterial performance comparable to conventional antibiotics. The photocatalytic degradation properties targeting the model β-blocker contaminants propranolol and atenolol showed increased degradation under UV light.
Current work includes the identification and characterization of wastewater isolates from three water treatment sites within Upstate South Carolina to assess nanocomposite efficacy under environmentally relevant conditions. Future investigations will expand applications toward cancer cell line studies, A549- human lung carcinoma and L929- mouse fibroblast, and activity against BSL-2 pathogens.
Collectively, these findings demonstrate that environmentally sustainable, plant-based Ag-TiO₂ nanocomposites represent a promising and cost-effective approach to wastewater disinfection, contaminant degradation, and emerging biomedical applications.
Keywords
Nanocomposite, Phytomediated, Noble Metal Doped, Photocatalytic, Antimicrobial, Biomedical
Start Date
10-4-2026 3:10 PM
Location
CASB 105
End Date
10-4-2026 3:25 PM
NS4 - Dual Plant Mediated Ag-TiO₂ Nanocomposites Antimicrobial and Photocatalytic Applications
CASB 105
Antimicrobial resistance and persistent pharmaceutical contaminants continue to threaten aquatic ecosystems and public health, creating an urgent need for sustainable and multifunctional remediation strategies. In this work, green-synthesized silver-doped titanium dioxide (Ag-TiO₂) nanocomposites were developed using silver-doping to decrease the band gap of TiO₂ for the nanoparticle to utilize a broader spectrum of low UV and high visible light waves. Moringa oleifera leaf extract is harnessed as a natural reducing and stabilizing agent, followed by photosensitization with Clitoria ternatea (butterfly pea) flower extract for enhanced antimicrobial and photodegradation activity. This phytomediated synthesis minimizes harsh chemical inputs while promoting enhanced light absorption and antimicrobial functionality.
Silver-doped titanium dioxide (Ag-TiO₂) nanocomposites were synthesized via a phytomediated approach. Titanium propoxide (TPP) and isopropanol were used as the primary reactants, while Moringa oleifera leaf extract served as a natural reducing and stabilizing agent. A silver nitrate solution was added, and the solution was mixed for 6 hrs at 85 ºC. The precipitate was dried for 3 hr at 110 ºC and calcinated at 400 ºC. The resulting nanocomposites were photosensitized with Butterfly Pea Flower extract by soaking the nanocomposites in the extract in the dark for 24 hr. FTIR, pXRD, and UV-Vis were used to characterize the nanocomposites. To test the antimicrobial properties colony-forming unit (CFU), optical density (OD), and Kirby-Bauer disk diffusion tests were completed against gram-negative and gram-positive bacterial controls. β-blocker pharmaceutical waste models, atenolol and propranolol, were used to test the nanocomposites' ability to degrade harmful toxins in water treatment while exposed to UV radiation for 2 hrs and measuring the degradation of pharmaceutical wastes using UV-Vis.
Antimicrobial activity was evaluated against gram-negative and gram-positive bacteria using CFU, OD, and Kirby-Bauer disk diffusion assays. The 5% Ag-TiO₂ nanocomposite achieved 88.3% inhibition of E. Coli K-12 and 89.5% inhibition of E. Coli B, demonstrating strong antibacterial performance comparable to conventional antibiotics. The photocatalytic degradation properties targeting the model β-blocker contaminants propranolol and atenolol showed increased degradation under UV light.
Current work includes the identification and characterization of wastewater isolates from three water treatment sites within Upstate South Carolina to assess nanocomposite efficacy under environmentally relevant conditions. Future investigations will expand applications toward cancer cell line studies, A549- human lung carcinoma and L929- mouse fibroblast, and activity against BSL-2 pathogens.
Collectively, these findings demonstrate that environmentally sustainable, plant-based Ag-TiO₂ nanocomposites represent a promising and cost-effective approach to wastewater disinfection, contaminant degradation, and emerging biomedical applications.