# Irradiation Enhances the Biomedical Functional Characteristics of Collagen Sponges: A Potential Strategy for Medical Collagen Sponge Modification

## TL;DR

This study shows that irradiation improves the properties of collagen sponges, making them more effective for controlling bleeding and wound care.

## Contribution

A novel method using low-dose gamma irradiation to enhance collagen sponges' hemostatic and antibacterial properties is introduced.

## Key findings

- Low-dose gamma irradiation (1–3 kGy) improves mechanical strength, elongation, and biostability of collagen sponges.
- Irradiated sponges show better water absorption, blood cell adsorption, and antibacterial properties than commercial alternatives.
- Spectroscopic analysis confirms chemical bond modifications without loss of crystallinity, and in vivo tests show biocompatibility.

## Abstract

Developing safe and effective hemostatic materials is critical for rapid bleeding control and wound management. However, traditional hemostatic materials using chemical crosslinking often fall short in hemostatic efficiency and carry risks of secondary injury from reagent residues. This study introduced an irradiation-fabricated composite collagen sponge based on fish skin collagen, chitosan, and soluble starch. The sponge was prepared via material solution blending, followed by cobalt-60 gamma irradiation at various doses, with casting and freeze-drying. Its functionality and safety were systematically evaluated. The results show that low-dose gamma irradiation (1–3 kGy) applied to a precursor solution prior to freeze-drying promoted intermolecular crosslinking, improving mechanical strength, elongation, and biostability, while higher doses (6 kGy) slightly reduced crosslinking due to the partial degradation of collagen, chitosan, and starch. With low-dose irradiation, the proposed hemostatic sponges show enhanced water absorption, blood cell adsorption, swelling, and antibacterial properties, indicating effective hemostatic performance. Spectroscopic characterization confirmed chemical bond modifications with no loss of crystallinity. Cytotoxicity and in vivo tests demonstrated biocompatibility and effective hemostatic performance. Compared with the commercial HSD sponge, the irradiated sponges exhibited superior hemostatic efficacy. This study presents that a collagen-based synergistic matrix prepared by gamma-ray irradiation can produce a hemostatic sponge with enhanced absorbency, bioactivity, and antibacterial properties, highlighting its great potential in rapid hemostasis and wound care applications.