Experimental study on the process and performance of chitosan-based SWCNT Pre-Dressing-Assisted laser joining of skin tissue

Abstract

As the first barrier against external aggression, the skin’s efficient repair capability is essential for maintaining homeostasis. To address the challenges of prolonged healing periods and high infection susceptibility in deep dermal (Grade III) wounds, single-walled carbon nanotube (SWCNT) solder-assisted laser joining technology enhances light absorption in biological tissues. However, this approach risks inducing severe thermal damage. While chitosan matrices promote healing, their inherent limitation lies in insufficient bonding strength. By integrating chitosan with SWCNT solder to assist laser joining of skin tissues, this strategy improves tensile strength at incision sites, stabilizes laser energy absorption, and mitigates thermal damage. In this study, a chitosan-SWCNT pre-dressing was developed to enable precise laser-assisted joining of skin tissue incisions. Results demonstrated that under optimized parameters (laser power: 4.5 W, scanning rate: 260 mm/s, defocus distance: 1 mm), the tensile strength of skin tissues reached 0.540 MPa when using 4 % (w/v) chitosan-SWCNT pre-dressing, representing a 42.1% improvement over prior methods. Concurrently, the thermal denaturation degree was reduced to 0.285, validating the technique’s efficacy in balancing mechanical performance and thermal safety.