The COVID-19 pandemic has increased worldwide concern about high-touch surfaces promoting the spread of contamination. Researchers are exploring surfaces and coatings that can minimize the presence of active viral pathogens for use in various environments. A lot of research has been conducted to investigate solutions to prevent the bacterial spread and biofilm formation by killing and/or reducing microbial attachment. These are achieved through surface-bound active antibacterial agents and biocidal coatings or passive pathogen rejection surfaces using nanomaterials, chemical modification, and micro and nanostructure development.
Alfa Chemistry provides customers with nanomaterials with antiviral properties, namely copper, silver, zinc and titanium dioxide, etc. We do our best to meet all your experimental needs for antibacterial coatings.
Figure.1 Schematic diagram of the current research and emerging antiviral coatings and surfaces, including metal and inorganic nanomaterials, polymeric and organic coatings, and emerging technologies such as omniphobic pathogen-repellent coatings. (Imani S. M, et al. 2020)
|Copper is probably the most widely used antibacterial metal to date. Various antibacterial mechanisms of copper have been determined through bacterial studies, such as plasma membrane permeabilization, membrane lipid peroxidation, protein changes, protein assembly and activity inhibition, or nucleic acid denaturation. CuNPs have broad application prospects on antibacterial and antiviral surfaces due to their small size and high surface area to volume ratio.
|Silver inactivates viruses by interacting with virus envelopes and virus surface proteins, blocking virus penetration into cells, blocking cellular pathways, interacting with viral genomes, and interacting with viral replication factors. Studies have shown that AgNPs can be used as early antiviral drugs to disrupt virus replication. AgNPs can be combined with many different materials to provide antiviral capabilities.
|The mechanism of pathogenic inactivation in TiO2 is related to light absorption, electron/hole generation, and ROS oxidation of organic materials, such as superoxide anions and hydroxyl radicals generated by valence band holes and conduction band electrons. Studies have proved that TiO22colloidal nanoparticles have excellent antibacterial and antiviral activities.
Other inorganic antiviral materials
|AuNPs can be used in combination with other more virus-killing metals (such as copper). Different surface modifications and combinations with other bioactive metals (such as copper or iron) have been used to achieve antibacterial functions.
Studies have shown that the influenza A/PR/8/34 (H1N1) virus is completely inactivated on glass coated with silica nanoparticles treated with didodecyl dimethyl ammonium bromide (DDAB).
Polyelectrolyte coating surface
|It has been shown that the positive charge of polycations in polymers such as polyethyleneimine will attract viruses with inherent negative charges, interfere with their genome content or structural units, and cause the virus to completely decompose. This type of coating is usually applied by "painting" and can permanently deliver antibacterial properties even after multiple washings.
|Some recent studies have integrated photosensitive compounds other than TiO2 (such as Rose Bengal and C60) onto the surface to take advantage of the ROS-dependent antibacterial and antiviral pathways. The working principle of antibacterial photodynamic inactivation is that the photosensitizer is excited by visible light absorption and then reacts with oxygen.
Figure.2 Polycation coatings. (a) Mechanism of enveloped virus inactivation by polycation coating. (b) SEM images of influenza virus after exposure to uncoated (i) and N,N-dodecyl,methyl-PEI-coated (ii and iii) silicon wafers. (c) SEM images of a polyethylene surface coated with Quat-12-PU nanoparticles: (i) top view and (ii) cross section. (Imani S. M, et al. 2020)