Researchers at the Hanoi University of Science have proposed a unique solution: using TiO2 nanoparticles with strong antibacterial properties to create face masks. This idea could be an effective measure to combat avian influenza and SARS.
Globally, it is known that TiO2 nanoparticles (in the nanometer range) generate powerful oxidizing agents such as H2O2, O2-, and OH- under light exposure, which are hundreds of times stronger than common oxidizers like chlorine and ozone. Consequently, it can decompose most organic compounds, toxic emissions, bacteria, and mold on surfaces into harmless substances like carbon dioxide and water vapor.
Based on this characteristic, Associate Professor Pham Van Nho from the Applied Physics Laboratory, Faculty of Physics, Hanoi University of Science, suggests that TiO2 nanoparticles can be used on a polyester cotton base to form the middle layer of face masks, helping to capture and eliminate harmful bacteria and viruses such as tuberculosis bacteria, SARS virus, H5N1, etc.
“Face masks are a cost-effective tool for preventing respiratory infections. However, until now, medical masks only provide mechanical filtration, meaning they trap small particles on their surface but do not kill bacteria, allowing them to survive,” Dr. Nho stated.
Moreover, he noted that this mechanical filtration capability is limited, even with active materials (for example, the standard N95 masks used against SARS). Therefore, over time, the protective capability of these masks diminishes.
“In contrast, TiO2 nanoparticles function on a catalytic principle, meaning they do not get consumed. There is no ‘habituation’ phenomenon with the material, thus providing much better protection for users,” he explained.
Experimental results from the Biology Department at the Hanoi University of Science show that TiO2 nanoparticles can kill E. Coli and Bacillus bacteria for at least three days, and in practice, this capability remains after 15 days. Dr. Nho mentioned that theoretically, TiO2 nanoparticles could also kill viruses, but actual testing is pending. He is currently presenting this idea to the Ministry of Health for consideration.
Regarding the safety of the product, Dr. Nho believes that the TiO2-containing layer is sandwiched between two other layers, preventing direct contact with human skin, thus posing no danger. He also stated that TiO2 has long been recognized as a safe material, still used in the production of sunscreen and in odor-neutralizing clothing.
Currently, the research team plans to collaborate with Red Star Company (Hanoi) to produce the face masks. It is estimated that each mask will cost between 30,000 to 50,000 VND depending on the type (with N95 masks currently priced around 3 USD). The nano masks will come in two types: one for general public use, which can be washed (losing its antibacterial effect after approximately ten washes), and another type for doctors and healthcare workers that does not require washing.
Although functioning on a photocatalytic mechanism, Dr. Nho noted that even in darkness, the material continues to exhibit antibacterial effects after being activated by light. “Theoretically, this capability lasts for weeks, and in practice, I have observed it lasting for hours,” he said.
This is not the first time Vietnam has applied nano TiO2 material technology. A recent study by Dr. Tran Thi Duc, Deputy Director of the Institute of Applied Physics and Scientific Equipment (Vietnam Academy of Science), also developed a self-cleaning paint made from nano TiO2, with broad potential applications in daily life and healthcare. However, this is the first instance in Vietnam where this material is used to produce antibacterial face masks.
In the context of the current avian influenza situation, Dr. Nho hopes this new idea will help prevent the risk of a pandemic outbreak and protect human lives. He also stated that although he has registered a patent for this useful solution, in case of an emergency (like a pandemic), he is willing to disclose the technology for everyone to create their own masks.
The solution emerged accidentally during the research team’s application of TiO2 in solar cell production.
Contact: Project Leader Associate Professor Dr. PHAM VAN NHO
Email: [email protected]
Mobile: 0912 179 053
Bich Hanh