However, joining these hydrogel polymers together quickly and reliably has been challenging. Current methods need improvement in strength and speed, often requiring complex, time-consuming processes.

Chitosan: The key to instant bonding

At the core of this innovation is chitosan, a natural polymer derived from the shells of crustaceans, such as shrimp and crabs. This material is known for its biocompatibility, biodegradability, and non-toxic nature, making it an ideal candidate for medical applications.

Here’s how researchers used it: they applied a thin layer of chitosan to the surfaces of the hydrogels they want to connect. This layer quickly absorbs water from both hydrogels, causing its sugar molecules to mix with the polymer molecules in the gels.

This mixing creates strong, non-chemical bonds through electrostatic forces and hydrogen bonding between different molecules. These bonds are surprisingly strong and can withstand extreme pulling, making the connected hydrogels more durable and useful for various medical purposes.

Advantages over traditional methods

This new method for bonding hydrogels offers significant advantages :

• Speed: Unlike conventional methods that rely on slow chemical reactions, the chitosan-based approach works instantly. This makes it incredibly valuable in medical situations where timely intervention is crucial, such as during surgery.
• Strength: The resulting bonds formed through this method are notably stronger than those achieved through traditional means. This stronger adhesion translates to greater reliability and durability of the bonded hydrogels.
• Simplicity: The process avoids the complexities of conventional methods, which often involve intricate chemical reactions or potentially harmful substances. This simpler approach makes implementing it safer and easier, minimizing potential complications.
• Versatility: This technique allows it to bond the same type of hydrogels. It can effectively join different hydrogel layers, various polymers, and even other materials, significantly expanding its potential applications across various fields.

Implications for medical applications

Hydrogels’ quick and efficient bonding unlocks novel possibilities in the medical field. These jelly-like materials, whose stiffness can be adjusted, allow us to engineer them to resemble the mechanical properties of specific tissues closely. This opens doors to various applications.

For instance, we can incorporate flexible electronics within these hydrogels for on-demand medical diagnostics. Additionally, this technique can create self-adhesive wraps, which are particularly useful for body parts that pose bandaging challenges.

Furthermore, the ability to bond hydrogels addresses a significant clinical obstacle: surgical adhesions. These unwanted bonds form between tissues after surgery, causing pain and complications.

Utilizing chitosan-bonded hydrogels can effectively create a barrier between tissues during surgery, minimizing the risk of these adhesions. This translates to faster healing, reduced pain, and fewer patient complications.

The findings of this innovative technique are published in the Proceedings of the National Academy of Sciences (PNAS).