Grantee Research Project Results
Final Report: Dual action anti-viral surface cover for high touch surfaces
EPA Contract Number: 68HERC21C0023Title: Dual action anti-viral surface cover for high touch surfaces
Investigators: James, Trevor
Small Business: Sonata Scientific LLC
EPA Contact: Richards, April
Phase: I
Project Period: March 25, 2021 through September 24, 2021
Project Amount: $100,000
RFA: Small Business Innovation Research (SBIR) - Phase I (2021) RFA Text | Recipients Lists
Research Category: Small Business Innovation Research (SBIR) , SBIR - Homeland Security
Description:
Contaminated surfaces are a major route for disease transmission and the COVID-19 pandemic has made the public acutely aware of the impacts of contaminated surfaces on human health. Viruses and bacteria such as rhinovirus, norovirus, influenza, and MRSA can be debilitating or deadly, are highly transmissible by surfaces, and can survive there for hours to days. There is a need for a surface that provides continuous, passive disinfection against a broad range of viruses and bacteria to help reduce the spread of these diseases, especially in high traffic and densely populated areas.
Sonata Scientific is developing a dual-action surface cover made from extruded thermoplastics that provides continuous disinfection against a broad range of viruses and bacteria. The antimicrobial/antiviral activity is provided by a blend of quaternary ammonium compounds and visible light activated photocatalysts, both of which are strongly adhered to high surface area supports creating a mechanically strong, non-leaching composite. The composite is directly embedded into a thermoplastic extrusion that facilitates direct contact between the composite and viral particles or bacterial cells. The composite is also separated from the underlying plastic matrix. The surface cover is designed to mechanically fasten to any high touch surface allowing it to be used in a variety of public settings.
Summary/Accomplishments (Outputs/Outcomes):
In the Phase I program, Sonata Scientific created two types of surface covers. One was fabricated by pressing the antimicrobial/antiviral composite directly into a heated thermoplastic and the other used high volume plastic extrusion where the composite was preblended with a thermoplastic. The pressed sample represented a cover with a high surface loading in the same form factor as a final product concept and was used to ensure activity of the composite. Extrusions were used to demonstrate high-volume manufacturing capabilities and resulted in a homogeneous distribution of the antimicrobial/antiviral composites. Both preparations maintained the fidelity of the composites, no change in size or cracking was observed after introduction into the thermoplastic. Sonata Scientific has a pathway to increase the surface loading of extrusions.
The antimicrobial/antiviral activity of both surface preparations was promising. A 99% reduction in viable MS2 bacteriophage, a surrogate viral pathogen, was realized after a 2-hour exposure on pressed samples that contained the QAS. Similarly, a 90% reduction for the photocatalyst after 2 hours of exposure in dark and visible light illuminated conditions. Bacterial viability was examined using S. aureus on the extruded samples that contained a blend of photocatalyst and QAS. A 99.9% reduction was observed after 1 hour exposure to visible light. Sonata Scientific continues to study the activity of these surfaces against a variety of bacteria and viruses.
No changes in wear resistance, measured using Taber wear testing, were observed on thermoplastic extrusions containing the antimicrobial/antiviral composite indicating the additives had no effect on the underlying physical properties of the plastic. Likewise, exposure to household chemicals did not adversely affect any of the surfaces and, in some cases, enhanced the performance of the surfaces toward bacteria removal.
Conclusions:
The dual-action surface cover is an effective way to reduce bacterial and viral loads passively on surfaces. In Phase I, we demonstrated a strong performance of model surface covers against MS2 bacteriophage and S. aureus. The pressed samples show the surface is active against viruses when there is a high surface density of the antimicrobial/antiviral composite. Extruded samples demonstrated a path to large scale manufacturing while also showing activity against bacteria despite a large fraction of the composite being unexposed. Creating a cover with a high surface density of the antimicrobial/antiviral composite using extrusion techniques will result in a highly active, durable surface cover. The resistance to abrasive wear is controlled by the base plastic ensuring the surface cover can withstand years of use while enhancement from chemical exposure offers potential augmentation of antimicrobial/antiviral activity when used in combination with regular cleanings.
Sonata Scientific was able to partner with a leader in thermoplastic formulation and extrusion to produce extrusions that contained the antimicrobial/antiviral composites. We continue to work with them on formulation and device architecture. This company has helped Sonata Scientific identify additional extrusion manufacturers capable of commercial extrusions that will help realize a high surface loading of the antimicrobial/antiviral composites.
Internal research by Sonata Scientific has indicated public transit, schools, and shopping centers as good entry points for this product. These markets all experience high traffic and rely on customer safety and well-being to operate effectively. After early adoption the product would benefit any public setting, especially healthcare, where infectious complications such as hospital-acquired infections are a well-known problem.
The perspectives, information and conclusions conveyed in research project abstracts, progress reports, final reports, journal abstracts and journal publications convey the viewpoints of the principal investigator and may not represent the views and policies of ORD and EPA. Conclusions drawn by the principal investigators have not been reviewed by the Agency.