sanitization
indoor air
Photocatalysis has proven to be extremely effective in eliminating a broad spectrum of microorganisms.
The photocatalytic process does not simply kill bacterial cells; it causes their complete decomposition through an advanced biochemical process.
indoor air quality: the importance of VOCS
Often underestimated
For most of our day, we breathe in closed environments, home, and office: this air quality should therefore concern us most.
In addition to viruses and microorganisms, volatile organic compounds are constantly indicated among the most significant pollutants in indoor environments.
The sources of Volatile Organic Compound (VOC) pollution in indoor air are diverse and concern little all objects and domestic activities: first of all, building and furnishing materials (whose emissions persist even for years), cosmetics or deodorants, cigarette smoke, cleaning materials and various products (e.g. glues, adhesives, solvents, paints), recently laundered clothes, heating devices, printers, and photocopiers.
Air quality therefore does not concern only "external" environmental pollution but, even more so, closed residential and working environments, since volatile organic compounds exist as gases at room temperature and the main route of exposure is through normal breathing.
Fotocatalisi: una potente tecnologia di sanificazione aria
Efficacy of Photocatalysis against Pathogens
Photocatalysis has proven to be extremely effective in eliminating a broad spectrum of microorganisms. Its action is not limited to Gram-negative and Gram-positive bacteria (including resistant endospores), but extends to fungi, algae, protozoa, and viruses, even inactivating prions. Unlike traditional methods, photocatalysis is also capable of degrading residual microbial toxins.
Among the scientific demonstrations of this capability, we cite Vincenzo Romano Spica, Professor of Hygiene and head of the epidemiology and biotechnology laboratory at the University of Rome 'Foro Italico', who stated: *“it is certainly a useful technology in hospital or healthcare environments, but it can be used wherever it is necessary to keep microbial and bacterial loads under control“.
The photocatalytic process does not simply kill bacterial cells; it causes their complete decomposition through an advanced biochemical process.
ROS Production: Catalyst activation generates reactive oxygen species (ROS), such as hydroxyl radicals and hydrogen peroxide. Structural Degradation: These species directly attack the cell wall and the cytoplasmic membrane. Lysis and Leakage: Damage to the membranes causes the leakage of cellular contents and the subsequent lysis (rupture) of the cell. Mineralization: The process can culminate in the complete mineralization of the organism, transforming organic matter into inert substances (such as water and CO2).
Why is Titanium Dioxide Superior? Titanium dioxide outperforms common antibacterial agents for several fundamental reasons: Overcoming Biofilm: The photocatalytic reaction acts directly on the contact surface, successfully bypassing the protective biofilm shield created by bacteria—a barrier where traditional chemical sanitizers often fail. Endotoxin Decomposition: While many disinfectants leave behind toxic residues after cell death, photocatalysis actively decomposes the released endotoxins. Continuous and Long-lasting Action: TiO2 acts as a catalyst and is not consumed during the reaction, ensuring a constant antibacterial and virucidal effect over time.
Comparative Performance
In terms of disinfecting power, Titanium Dioxide delivers significantly higher performance than conventional systems: 3 times more effective than chlorine and 1.5 times more effective than ozone.
Integrating photocatalysis into conventional air filtration systems offers a strategic advantage: in addition to purifying the airflow, it makes the filters themselves self-cleaning. This prevents bacterial proliferation on the filter media, reducing maintenance and improving environmental quality over the long term.
Photocatalysis triggered by UVC radiation
a perfect match
The sterilizing effects of ultraviolet germicidal irradiation (UVGI) were discovered in the late 19th century and established in the 20th century. UVCs modify the DNA or RNA of microorganisms, preventing them from reproducing or being harmful.
The recent pandemic has raised awareness of air sanitation, and studies on the germicidal efficacy of UVC have been further validated.
Since the TiO2 photocatalytic process is also activated by emissions in the UVC range, the two systems are excellent partners for the development of a filtering system that, in a single passage, reduces:
- VOC
- Bad odors
- Germs, bacteria and viruses
So why not take advantage of this opportunity to provide a total response to a problem that is comprehensive?
All filters in the Depurex photocatalytic range can be activated by a UVC light source to achieve an exceptional level of purification.
Photocatalytic filtration, combined with UVCs, is the most advanced response for creating air treatment units that are truly effective in reducing indoor pollution and air sanitation.
Further reading:
World Health Organization – Guidelines for indoor air quality