Tough polyacrylamide-tannic acid-kaolin adhesive hydrogels for quick hemostatic application

Area of Science:

• Biomaterials Science
• Tissue Engineering
• Hemostasis

Background:

• Adhesive hydrogels are crucial for biomedical applications on wet and dynamic tissues, facing challenges in achieving mechanical strength, adhesion, and hemostatic efficiency.
• Existing hydrogels struggle to meet the demands of cyclic loading, such as in controlling hemorrhaging on curved surfaces like skin and heart tissues.

Purpose of the Study:

• To develop novel adhesive and hemostatic hydrogels inspired by mussel and slug adhesive behaviors.
• To create polyacrylamide-tannic acid-kaolin (PAAm-TA-KA) hydrogels with enhanced mechanical properties, strong adhesion, and effective hemostatic capabilities.

Main Methods:

• Fabrication of polyacrylamide-tannic acid-kaolin (PAAm-TA-KA) hydrogels utilizing physical and chemical crosslinking.
• Incorporation of tannic acid for catechol groups and kaolin nanoparticles as physical crosslinkers and FXII activators.
• Evaluation of mechanical properties, adhesion strength on porcine and human skin, and hemostatic efficiency.

Main Results:

• The PAAm-TA-KA hydrogels exhibited high strength and toughness due to their crosslinking structures.
• Strong and durable adhesion up to 500 kPa on porcine skin was achieved, with easy removal from human skin without damage.
• Kaolin nanoparticles activated factor FXII, accelerating thrombus formation and enhancing hemostatic efficiency.

Conclusions:

• The developed PAAm-TA-KA hydrogels possess significant adhesive and hemostatic properties suitable for wet tissue applications.
• These cytocompatible, tough, and adhesive hydrogels demonstrate high potential as advanced materials for traumatic bleeding control.