“Clothing can be antibacterial and antiviral”, is it really effective or just a waste of money?

After experiencing the COVID-19 pandemic, consumers have become more enthusiastic about antibacterial and antiviral materials. Recently, there are more and more clothing and textiles on the market that claim to have "antibacterial and antiviral" functions. So how do these functional products work? What are their actual effects? What should consumers pay attention to when purchasing such products to protect their health?

Let me first state the conclusion:

Antibacterial and antiviral fabrics really exist and have been widely used for a long time, but when it comes to preventing infection with the new coronavirus, we still need to consume rationally and take scientific measures to prevent the epidemic.

01

Can clothing be antibacterial and antiviral?

In fact, the application of antibacterial and antiviral fabrics has a long history. The most common hemp fibers (flax, hemp, ramie, etc.) are natural antibacterial materials . This is mainly because hemp plants contain flavonoid compounds, which have good antibacterial effects. At the same time, hemp fibers have a hollow structure, which makes the oxygen content in the fiber higher, which also helps to inhibit the production of anaerobic bacteria.

Copyright image, no permission to reprint

Generally speaking, the antibacterial property of textiles is to inactivate bacteria by inhibiting or destroying their reproductive capacity . The antiviral property of textiles is to inhibit or destroy the ability of viruses to infect host cells by changing the protein structure on the surface of viruses or destroying their structure through the chemical adsorption of antiviral substances.

02

Antibacterial and antiviral clothing fabrics

There are these ideas

Let's talk about the common ideas for achieving antibacterial and antiviral functions:

First, in order to achieve the antibacterial and antiviral function of fabrics, the most commonly used method in industry is to use antibacterial and antiviral preparations to treat textiles including fibers, yarns, and fabrics . For example, nano silver ion preparations are coated or impregnated on fabrics to make nano silver ions adhere to the surface of the fabric (mainly for antibacterial purposes).

Under certain conditions, silver ions can destroy viral DNA, thereby achieving an antiviral effect, but current research on the effect of silver ions on the new coronavirus is not sufficient.

Secondly, another method is to make the antibacterial and antiviral preparation into microcapsules, apply them to the surface of the fabric , and when the wearer uses it, the fabric rubs against the fabric, causing the microcapsules to rupture and gradually release the antibacterial and antiviral ingredients, achieving the antibacterial and antiviral effect.

A recently reported fabric that uses the " electron beam grafting method " to achieve antiviral function uses the electron beam generated by an electron accelerator to open the chemical bonds on the macromolecules on the fiber surface, and then "grafts" the antiviral agent molecules into the fiber macromolecules. When the antiviral agent molecules encounter the virus, they will pierce the viral envelope, thereby achieving the purpose of killing the virus.

Schematic diagram of the antibacterial mechanism of cotton fabric modified by grafting of cationic antibacterial monomers. Image from the Internet

In addition to the above-mentioned antibacterial and antiviral preparation treatment methods, there are also methods that utilize the characteristics of the material itself or adopt special structures to achieve antibacterial and antiviral purposes .

For example, artificially extracted chitosan fibers have better antibacterial properties . Positively charged chitosan can generate electrostatic attraction with negatively charged substances on the surface of bacteria, greatly changing the permeability of the cell membrane and causing important substances in the cell to leak out, thereby killing bacterial microorganisms.

Graphene materials also exhibit good antibacterial and antiviral properties. The fabrics are processed and modified using small graphene nanosheets with nano-scale sizes and special-shaped structural edges such as pointed or serrated shapes.

The vertical ultra-thin structure, horizontal nano-scale size, and pointed or serrated edges of small-layer graphene nanosheets give the fabric small and sharp edges at the microscopic level. When in contact with bacteria or viruses, small-layer graphene nanosheets can pierce the cell wall of micron-sized bacteria to kill them, or pierce the protein film of nano-sized viruses, thereby inhibiting the replication of the virus, and ultimately achieving the purpose of antibacterial and antiviral effects on a variety of bacteria. However, this path has not yet achieved large-scale market application.

Chemical material graphene molecule. Copyright image, no permission to reprint

03

Antiviral clothing

Is it really a tax on IQ?

At present, the effectiveness testing of antibacterial textiles in my country mainly adopts the national standards GB/T 20944.1-2007 "Evaluation of Antimicrobial Properties of Textiles Part 1: Agar Plate Diffusion Method", GB/T 20944.2-2007 "Evaluation of Antimicrobial Properties of Textiles Part 2: Absorption Method", GB/T 20944.3-2008 "Evaluation of Antimicrobial Properties of Textiles Part 3: Oscillation Method", and the effectiveness testing of antiviral textiles mainly adopts the international standard ISO 18184 "Determination of Antiviral Activity of Textiles".

Many businesses claim that their antibacterial and antiviral products meet relevant national or international standards. However, such test results are usually theoretical data and conclusions obtained under laboratory conditions. There is still a certain difference between laboratory conditions and complex actual conditions .

Copyright image, no permission to reprint

Especially for the current COVID-19 epidemic, judging from its transmission method, washing hands frequently, ventilating frequently, and insisting on wearing masks are still the most important means of prevention. Wearing antiviral clothing may only be icing on the cake, because antiviral clothing only has an inhibitory effect on viruses adhering to the surface of clothing, and has no effect on the COVID-19 spread in the air .

Some of you may have questions. Since this type of clothing seems to have very limited effect against the new coronavirus, is buying antibacterial and antiviral clothing or textiles a waste of money?

In fact, as mentioned at the beginning of the article, the application of antibacterial and antiviral materials has a long history and has produced good results in actual use. For example, the application of antibacterial fibers in underwear, socks, and medical textiles is very mature and can inhibit Staphylococcus aureus, Escherichia coli, Candida albicans, etc.

The development and use of antibacterial and antiviral fabrics are of great significance to improving the user's wearing experience and health. With the development of technology, such functional products will become more and more mature. However, returning to the current issue of the new coronavirus infection, it is still strongly recommended that everyone consume rationally and prevent the epidemic scientifically.

References:

[1] Zhang Jie. Research on the natural antibacterial properties of hemp fiber[D]. Donghua University, 2018.

[2] Wang Zhicheng. New long-lasting antiviral textiles[J]. Fujian Textiles, 2023(01):3-4+9.

[3] Wang Xiang, Li Jingye, Liu Tiantao, Yu Ming. Research progress on antibacterial and antiviral properties of textiles[J]. Printing and Dyeing Auxiliaries, 2022, 39(09): 6-12.

[4] Deng Tong, Liao Shihao, Huang Xinxin, Wang Xuan, Shen Lanping, Chen Peng. Research progress of antibacterial yarn[J]. Wool Textile Science and Technology, 2022, 50(11): 128-133.

[5] Long Fuqiang, Song Jun, Li Kaihua. Research progress of antibacterial cellulose fibers[J]. Polymer Bulletin, 2022(07):29-38.

Author: Song Lidan

Reviewer: Zhang Jie, Chief Engineer of China Textile Construction Planning Institute

The cover image and the images in this article are from the copyright library

Reproduction of image content is not authorized