Anti-swelling hydrogel bioadhesive with integrated mechanical robustness and long-term stability for effective hemostasis

Hydrogel bioadhesives have emerged as promising hemostatic materials for clinical applications. However, their performance in wet environments is often compromised by swelling-induced weakened mechanical properties and insufficient tissue adhesion, resulting in adhesion failure and thereby impacting the hemostatic properties. Here, we have engineered a novel kind of poly (2-hydroxyethyl methacrylate)/poly (acrylic acid-co-N-hydroxysuccinimide acrylate ester) (PHEMA/PAA-NHS) double-network hydrogel bioadhesive integrating anti-swelling capability, high shear strength, high bursting pressure, and long-term mechanical stability in wet environments. We use a two-step sequential polymerization process along with cryogenic process to prepare PHEMA/PAA-NHS hydrogel bioadhesive. The first PHEMA network framework confers exceptional anti-swelling properties and mechanical stability, while the second PAA-NHS network provides robust wet tissue adhesion due to the existence of NHS. Meanwhile, cryogenic process endows the bioadhesive with a porous structure. PHEMA/PAA-NHS demonstrates integrated performance: minimal swelling (<100% quality change), ultrahigh bursting pressure (~450 mmHg), strong wet adhesion (~30 kPa), and long-term mechanical stability (after 5 days immersion). PHEMA/PAA-NHS is capable of facilitating rapid absorption of substantial blood volume and could enable prompt hemostasis, owing to the integrated mechanical properties and porous structure. Furthermore, PHEMA/PAA-NHS can monitor electrocardiogram and electromyogram, offering significant value for disease diagnosis. In conclusion, this study presents a new strategy for clinical hemostasis and bioelectronic applications.