Three metal oxides, made by bacteria, stronger together.
GreenOxide develops biogenic metal oxide nanoparticles, copper oxide, zinc oxide and tungsten oxide, as new antimicrobial agents. Combined, they showed above 90% antimicrobial activity against clinical isolates in the lab, including MRSA and Candida albicans.
Resistant infections need new agents.
Antibiotic resistance is pushing the search for antimicrobials that work differently.
Resistant bacteria
Methicillin-resistant Staphylococcus aureus (MRSA) is hard to treat with standard antibiotics.
Fungi too
Candida albicans from oral and vaginal samples is part of the same clinical challenge.
Single agents fall short
One agent alone may not reach high kill rates, which is why combinations matter.
Biogenic metal oxides that work in synergy.
The nanoparticles are made by a bacterium instead of harsh chemical synthesis, then used alone or combined. Combinations outperformed single nanoparticles in laboratory tests.
CuO and ZnO
- Effective in dark incubation
- Light did not change their effect
- Raised lipid peroxidation in microbes
WO3
- Photoactivated by light
- Effective across bacteria and Candida
- Highest lipid peroxidation under light
Synergy
- Higher activity than single nanoparticles
- Tested in dark and light
- Confirmed by live/dead staining
How it works
From bacterial synthesis to tested combinations.
- 1
Biogenic synthesis
A bacterium, Stenotrophomonas maltophilia, converts metal salts into oxide nanoparticles.
biogenicCuOZnOWO3 - 2
Characterisation
Particles are checked for size, structure and composition.
XRDFTIRSEMTEM - 3
Single and combined testing
Nanoparticles are tested alone and in combinations under dark and light incubation.
darklight - 4
Mechanism checks
Lipid peroxidation and live/dead staining show how the microbes are damaged.
MDAflow cytometrymicroscopy
Laboratory results
In vitro testing against clinical isolates of E. coli, S. aureus, MRSA and Candida albicans from oral and vaginal samples. No animal or human data yet.
| Treatment | Organism | Reported cell death |
|---|---|---|
| WO3, light | E. coli | 82.7% |
| WO3, light | S. aureus | 81.2% |
| WO3, light | MRSA | 78.3% |
| ZnO, dark to light | MRSA | 45.6% to 73.7% |
| Combinations, dark | Test organisms | Over 80% |
| Combinations, light | Test organisms | Over 90% |
Source: Francis et al., International Journal of Molecular Sciences 24(12), 9998 (2023). doi:10.3390/ijms24129998
Who it is for
Partners working on infection control.
Antimicrobial developers
- Synergistic nanoparticle combinations
- Activity against MRSA
- Light-activated option
Coating and materials companies
- Metal oxide antimicrobial agents
- Dark-active and light-active choices
- Green synthesis route
Clinical microbiology researchers
- Tested on clinical isolates
- Bacteria and Candida covered
- Mechanism data included
What we do not claim
Honest limits at this stage.
Laboratory evidence only
All results are in vitro, against isolates grown in the lab.
Human safety not yet tested
Effects on human cells were not assessed in this study.
Not a medicine
GreenOxide nanoparticles are not approved for any clinical or consumer use.
The team
Founded in 2024–2025 by the research team behind the biogenic metal oxide nanoparticle study.
Dali Vilma Francis
Co-author of the GreenOxide research.
Manju Nidagodu Jayakumar
Co-author of the GreenOxide research.
Hafiz Ahmad
Co-author of the GreenOxide research.
Trupti Gokhale
Co-author of the GreenOxide research.
Frequently asked questions
What does biogenic mean?
The nanoparticles are made by a living bacterium, Stenotrophomonas maltophilia, rather than by purely chemical synthesis.
Which microbes were tested?
Clinical isolates of E. coli, S. aureus, MRSA and Candida albicans from oral and vaginal samples.
Why combine three nanoparticles?
Combinations showed a synergistic effect, with antimicrobial activity above 90% compared with single nanoparticles.
What does light do?
Light activates WO3, which then reduced viable cells by 75% for all test organisms. CuO and ZnO worked in the dark and light did not change them.
Is it safe for people?
That is not yet known. The study did not test human cells, so safety work is a next step.
Peer-reviewed science behind GreenOxide.
Read the full study behind the product.
Francis, D. V., Jayakumar, M. N., Ahmad, H., & Gokhale, T. (2023). Antimicrobial activity of biogenic metal oxide nanoparticles and their synergistic effect on clinical pathogens. International Journal of Molecular Sciences, 24(12), Article 9998. https://doi.org/10.3390/ijms24129998
https://doi.org/10.3390/ijms24129998