What does ISO 20743 test method mean for a common textile businessman
The ISO 20743 test method standard contains quantitative tests for the determination of the antibacterial activity of all antibacterial substances, even nonwovens.
This ISO standard can be used to register a product with the appropriate authority.
All textile products, such as cloth, wadding, thread and material for clothing, bedclothes, home furnishings and miscellaneous goods are covered by ISO 20743:2013. This standard is applicable to all textile products, regardless of the type of antibacterial agent used (organic, inorganic, natural or synthetic), in our case the Si-Quat textile treatment.
The user can choose the most appropriate inoculation method for determining antibacterial activity based on the anticipated application, the environment in which the textile product will be used, as well as the surface properties of the textile. The following three inoculation methods are available for determining antibacterial activity:
Absorption technique is a type of assessment in which the test bacterial suspension is absorbed into the test tube.
Inoculation is done directly on the sample
Technique of assessment in which test microorganisms are put on an agar plate and then transferred onto specimens transfer method
The colony plate count method and the ATP (Adenosine Triphosphate) luminescence method are also described for counting the number of bacteria in a culture.
In general, rather than existing as free-living creatures, the majority of microbes are found adhering to surfaces. These bacteria then have the ability to spread to other areas, such as human skin or food products, if they come into touch with them. In the case that germs are moved to an environment that provides favourable development circumstances, they may multiply and eventually produce detrimental consequences in the humans who have been exposed to them. A surface that has been treated with an antimicrobial agent may be prevented from becoming a source of infection.
Types of techniques used for this testing
Consequently, antimicrobial surfaces are of considerable interest to both consumers and producers, and this is an area that has been aggressively advertised and pursued. A variety of antimicrobial agents have been immobilised onto a variety of surfaces, including nonporous surfaces (such as plastics and metals and porous surfaces (such as natural and synthetic fabrics. When tested using the ISO 20743 antibacterial test technique, it is anticipated that test samples will show a decrease in bacterial growth of at least 90 percent in most cases.
When unlaundered textiles are exposed to bacteria for 24 hours, they show a 2-log reduction (or 99 percent reduction) in bacteria when compared to an untreated, unlaundered cloth. When compared to an untreated, unlaundered cloth, laundered textiles (25 washings) showed a 1-log reduction (or 90 percent reduction) in germs after 24-hour contact time (or 25 washings).
Experimental setup and Impact
If antimicrobial surfaces are to be used, it is critical that they have been subjected to testing to validate their efficacy as well as offer scientific evidence to back any claims that the manufacturer chooses to make about them. The technique of testing should be repeatable, and special attention must be taken in determining critical factors such as experimental settings, usage of adequate controls, and the type and concentration of microorganisms that are employed. In fact, the type of microorganisms employed in the test will have an impact on the claims that may be made about the surface, such as whether it is antibacterial, antifungal, or antiviral, depending on the results.
Although there have been reports of some of the techniques described below being adapted to examine antifungal and/or antiviral effects, the focus of this article will be on conventional methods that employ bacteria as the test organisms.
Testing procedure in different Countries
The Japanese Industrial Standard JIS Z 2801 is the most often used test technique by manufacturers for non-porous (e.gplastic, metal, ceramic) surfaces. This generally accepted approach was developed by a partnership of research organisations, universities, and antibacterial agent manufacturers, which has now been universally accepted. The Japanese standard JIS Z 2801 served as the foundation for ISO 22196, the worldwide standard for the measurement of antibacterial activity on non-porous surfaces, and the two procedures are nearly identical in their results and interpretation. Both procedures include putting a droplet of a suspension of either Escherichia coli or Staphylococcus aureus directly onto the surface being examined with a microscope.
It is next necessary to apply a coverslip over the droplet, which helps to distribute the bacteria suspension and maintain it in close contact with the test surface. After a 24-hour incubation at 35°C, the bacterial suspension is released from between the coverslip and test sample sandwich, and the number of viable bacterial cells that have survived is assessed.
Further testing and advancements
However, the experimental circumstances are more of a best-case scenario for the antimicrobial surface under investigation rather than a representation of the conditions that are likely to occur in a real-world situation. A in addition, it is conceivable that germs clinging to the coverslip might have an impact on the findings of the experiment. Consequently, several researchers have decided to change their testing procedures to eliminate the need of a coverslip.
Method of Absorption — An assessment method in which a strain of test bacteria is injected directly onto the samples being evaluated. To calculate the antibacterial activity value, it is necessary to know the quantity of bacteria present immediately after inoculation and after a period of contact time. The standard response time is 18 to 24 hours.
Conclusion:
Test microorganisms are put on an agar plate and then transferred onto the samples in this technique of assessment. Transfer Method — For the first 5 minutes, samples are kept in touch with the bacteria, after which they are left to incubate for 18–24 hours. The number of bacteria present immediately after inoculation and contact is counted, and this quantity is used to calculate the antibacterial activity of the solution. ISO 20743 test method., therefore has proven to be extremely helpful in the diagnosis sector and general testing, this advancement was indeed much needed for the general well being of the world.
Also read - ISO 21702 As the enemy of viruses.
