ISO 18184 – Determination of Antiviral Activity of Textile Products
ISO 18184 is an antiviral textile test that measures virucidal antimicrobial activity on textiles and other porous materials.
The ISO 18184 test standard is designed to test the ability of textiles and other similar materials to kill virus. Standard virus exposure times range from 2 hours to less than 24 hours. Different viruses may have inherent sensitivity to the underlying material, so a control material is also included to determine the antiviral effects of the treated textile over any inherent antiviral performance of the test substance.
Many virus types can be tested; common examples include influenza and coronavirus strains. The actual performance of the treated textile is determined by viral titer measurements using a plaque assay or TCID50 method (Median Tissue Culture Infectious Dose) similar to a most probable number serial dilution measurement.
The ISO 18184
Common Antimicrobial Additives
Standard mechanisms for antiviral activity require additives that can chemically or dynamically modify some aspects of the virus. Drug strategies rely on highly specific binding to the virus (known as receptor-ligand binding) where the receptor is on the virus, and the ligand is the drug used to bind to the receptor blocking its mode of action.
For treated products, a more conventional approach is to chemically attack a more general aspect of the virus. For coronavirus, which has a fatty (lipid) envelope, antiviral products will adhere to the membrane and disrupt it by causing it to lose its characteristic shape and, therefore, its ability to infect. Standard classes of antimicrobials for that activity used in textiles are quaternary ammonium compounds, essential oils, and quaternary-silane molecules (quat-silane), which are similar to surfactants or detergents but are coupled with additional chemical functions to allow for their durable use.
Another mode of antiviral activity uses a different chemical approach that oxidizes the material on exposed surfaces of the virus; once oxidized, these viral components can no longer function biologically and are inactive. Characteristic classes of antiviral and antimicrobial compounds that use this strategy are chemicals like hypochlorite or bleach. These tend to be of less use due to a lack of durability, but are still used as an effective cleaning mechanism.
Many customers will request durability testing as a component of the ISO 18184 method to determine a products antimicrobial performance against viruses when exposed to environmental conditions. Utilizing both Durability and Antimicrobial testing through Situ Biosciences’ product test laboratory can support product development and performance testing while reducing the time and costs associated with developing and distributing quality products. One caution is that durability assessments need to be well controlled for the effects of residual cleaning products and, therefore, must be well designed for the intended purpose of the treated product.
For more information about ISO 18184 and antiviral treated products, contact the lab at 847-483-9950 or firstname.lastname@example.org.
Introductory ISO 18184 YouTube video: https://youtu.be/7pznYs9IvJk