Flexible wound dressings for active healing

Personal experience of the limitations of conventional dressings stimulated a researcher to develop a better solution

Original source: Materials Today

An article in the journal  describes adhesive wound dressings that are much more than mere sticking plasters. The dressings are composed of a flexible adhesive and self-healing hydrogel with antibacterial and other therapeutic properties built in. Their ability to move with the body and repair any damage to their own structure while remaining in place may prove especially useful for treating wounds around joints.

“Common cuts, abrasions, burns and trauma or surgery wounds can erode the body’s first line of defence, leading to more serious problems,” says researcher Baolin Guo, pointing out the widespread significance of developing better wound dressings. In addition to having inherent antibacterial properties, the new dressing material delivers protective antioxidants into a wound, while also promoting the overall stability of repairing tissues – a process known as .

Guo worked on the innovation with his colleagues at  in China, together with co-workers at the  in the USA. The research developed from Guo’s own personal dissatisfaction with the wound dressings he used on hiking expeditions. “My real life experience led our group to devote ourselves to designing next-generation hydrogel wound healing materials to improve the situation,” says Guo.

contain a network of long polymer chain-like molecules, often cross-linked, with large quantities of water surrounding the polymer chains. One of their most useful properties can be a , meaning that the integrity of the overall structure readily repairs itself after any breakage or deformation. This is especially useful for wound dressings that need to move and flex with a joint.

The mesh-like polymer network of Guo’s hydrogel is prepared by mixing a natural carbohydrate derivative called  with a complex synthetic carbon-based (organic) polymer. Adding circumin, a natural antioxidant and anti-inflammatory compound from the turmeric plant, provides additional wound-healing benefits.

The final structure is a mix of hydrogel polymers and small globules called . The micelles can carry molecules, such as the circumin, that bring additional healing properties to the system.

Tests on mice indicated that the dressing significantly accelerated wound healing. The specific benefits that the researchers detected included increased thickness of repaired tissue, greater deposition of the key skin protein collagen and activation of growth factor molecules involved in wound repair.

Guo lists other advantages over traditional dressings, including a porous structure that supports the desired presence of oxygen and the ability to absorb fluid released from a wound. The polymer structure can also be fine-tuned to suit different applications, by varying the key physical properties such as elasticity and tolerance of twisting, bending and stretching. The basic structure itself also provides an effective physical barrier to invading bacteria and an environment that inhibits bacterial growth.

The researchers now plan to explore further refinements. These include increasing the strength of the hydrogels and exploring their ability to deliver a variety of other drugs that could treat a wide range of specific injuries.

Article details:

Guo, B. et al.: “Antibacterial adhesive injectable hydrogels with rapid self-healing, extensibility and compressibility as wound dressing for joints skin wound healing” Biomaterials (2018)