“Bioactive” textiles are currently in full development: but why?
What are we talking about?
When you put on your shirt in the morning before going to work, it plays a simple “passive” role of protection: against the cold, the wind, the sun…
Unlike conventional textiles, which are limited to passive functions, “bioactive” textiles are designed to interact “actively” with the human body or other living organisms.
They therefore fall into the category of “smart textiles” designed to express a particular property.
Principles of functionalized textile manufacture
Textiles are finished to give them added value.
They can be made bioactive by modification, treatment or incorporation of active substances to confer specific functionalities. These may be antimicrobial agents, natural bioactive compounds, temperature regulators, controlled-release substances, etc.
There are now many different processes:
- We can use spinning technologies such as melt spinning[1] and electrospinning[2], which enable active ingredients to be incorporated into the fiber mass, or surface treatment techniques (plasma, electron bombardment, ultraviolet polymerization, excimer laser (UV), etc.), which enable bioactive molecules to be immobilized on the fiber surface. In these cases, the bioactive molecule is immobilized on the surface of the textile support, giving it long-term activity.
- Another strategy involves temporary immobilization and sustained release of therapeutic agents. A hydrogel- or cyclodextrin-based reservoir system interacts with the external environment to release the active ingredients.
[1] The polymer is melted and sent under pressure through the filière. On leaving the filière, the filaments are cooled, stretched and wound.
[2] Electrospinning is a fiber production method that uses electrical force to draw solution-charged or molten polymer yarns to diameters of the order of hundreds of nanometers.
Protective bioactive textiles
Antibacterial, antifungal and antiviral textiles are the best-known and most widely developed.
Antibacterial agents can kill (or significantly reduce the number of) bacteria: this is known as bactericidal action. Or they may inhibit the development of bacteria in contact with them, a process known as bacteriostasis. The duration of action depends on the manufacturing process. In this way, we can manufacture products with long-lasting action or single-use products.
The addition of these components to textile garments can influence the balance of the wearer’s skin microbiota. Although most antimicrobial textiles have demonstrated good biocompatibility, the question arises as to how these products affect the bacteria of the commensal flora essential to our immune system. See the article by Claudia Suellen Ferro de Oliveira and Freni Kekhasharú Tavaria cited in the references.
A further difference can be made between the various active agents in terms of their attachment to the textile substrate. Some can gradually migrate from the fiber or fabric to an external environment, where they come into contact with micro-organisms. This system can have disadvantages, such as the loss of carrier activity parallel to migration, or the presence of low concentrations of biocide at a distance from the textile, which can lead to the formation of resistant germs.
The main applications are in health textiles (gowns), underwear, sportswear, bed linen and towels, comforters and pillows, the inside of sports shoes… Some anti-odour textiles work by inhibiting the growth of odour metabolite-producing bacteria (Corynebacteria), sweat itself being odourless.
We have already discussed Ouvry CBRN gloves with antifungal properties and the properties of antimicrobial textiles.
What all these applications have in common is the notion of hygiene they can provide.
The main role of antifungal textiles is to protect surfaces against fungus (shower curtains, pool liners, etc.). They are also found in furnishing textiles to prevent allergy problems and deterioration due to the presence of mold.
We can also find
antioxidants (such as curcumin),
anti-inflammatories and painkillers (mineral blends),
anti-odour: product-loaded microcapsules are attached to the garment, eliminating organic odours such as ammonia, sweat and smoke,
body temperature regulators (ceramic nanoparticles), and much more.
Active biomedical textiles
They are sometimes referred to as “texticaments”.
The three main sectors of use are care and therapy devices, diagnostic and monitoring devices, and protective and hygiene devices.
The products used are considered medical devices under the regulations. They include orthoses, dressings, sutures, patches, implants and textile prostheses.
While dressings play a protective role, other textiles can be used to reinforce organs (e.g. inguinal wall hernias), or replace failing organs (e.g. arteries or tendons).
These new textiles play an active role in healing, activating or inhibiting thrombosis, supporting tissue regeneration (bone, skin, nerves…), and preventing post-operative complications (infection, adhesions, pain).
They enable more targeted medical treatments and are widely used in the medical field.
The oldest and best-known are antimicrobial dressings, which prevent wound infection and promote healing.
Some textiles are controlled-release. They deliver active substances such as drugs, antioxidants or cosmetics.
They help to heal wounds and may contain moisturizing substances to combat dry skin.
There are also hydrophilic textiles that attract and absorb moisture, helping to maintain a feeling of freshness and comfort. These can be found in underwear or sportswear.
Conclusion
As we have already seen, bioactive textiles interact with living organisms to enhance comfort (e.g. antimicrobial textiles) or to treat them.
They are mainly found in the health and wellness and medical fields.
Advanced spinning technologies for biostable or bioresorbable polymers and surface treatment technologies are often used, along with nanotechnologies, to implement two main strategies for developing bioactive textiles: long- or medium-term technology is achieved by grafting the bioactive molecule via stable chemical bonds, while short-term activity is produced using “reservoir” systems such as hydrogels and cyclodextrins that release active agents in situ.
References
Les textiles fonctionnels ou intelligents : https://textileaddict.me/les-textiles-fonctionnels-ou-intelligents/
Claudia Suellen Ferro de Oliveira, Freni Kekhasharu Tavaria. The impact pf bioactive textiles on human sin microbiota, European journal of Pharmaceutics and Biopharmaceutics, Volume 188, July 2023, Pages 66-77, https://doi.org/10.1016/j.ejpb.2023.05.004
Bernard Martel, Christine Campagne et Nemeshawaree Behary Massika, Quand les textiles vous soignent, Med Sci (Paris) 2017; 33:73-80
Manuel J Lis, Meritxell Martí, Luisa Coderch, Cristina Alonso, Fabricio M Bezerra, Ana P Immich, José A Tornero, Advances in textile engineering, Chapter 1, Biofunctional Textiles, 2019, https://digital.csic.es/bitstream/10261/181440/1/Biofunctional%20Textiles.pdf
Daniel Weidmann, Aide-mémoire : Textiles techniques, Dunod, https://www.dunod.com/sites/default/files/atoms/files/9782100543557/Feuilletage.pdf
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