Electrospun Core–Shell Bioadhesive Nanofiber Sheets Enable Durable Pulmonary Air Leak Sealing Under Wet and Dynamic Conditions

Pulmonary air leak is the most common complication following lung surgery. Most materials used for pulmonary fistula closure rely on fibrin network-mediated adhesion. However, on the moist and dynamically deforming lung surface, these materials often fail to provide sufficient adhesion, and postoperative air leaks remain a major clinical concern. Since these materials are biologically derived, concerns regarding biosafety risks and high production costs persist. To address these limitations, this study develops a novel closure material that integrates biocompatibility, pressure resistance, tissue adhesion, and seal retention under wet conditions. The closure material is fabricated as a nanofiber sheet via electrospinning. Comparative evaluation of different structural designs demonstrates that incorporating a core-shell nanofiber structure achieves a favorable balance of pressure resistance, tissue adhesion, and seal retention under wet conditions. Acute leak closure was evaluated in five animals, and long-term safety was assessed in three animals followed for 1 month. The mean air leak volume decreased from 46.2 to 1.8 mL/min, with post-treatment air leak volumes below the clinically accepted threshold (≤ 10 mL/min) in all five animals. No treatment-related complications were observed during the follow-up period. Thus, electrospun nanofiber sheets represent a promising and biosafe approach for pulmonary air leak closure.