Ultrathin Nanofibers Ameliorate Commercial Gauze for Rapid Hemorrhage Control Via Improved Clotting Kinetics and Rbc Modulation

Timely control of bleeding is critical for traumatic injuries necessitating effective anti-hemorrhagic biomaterials. Ultrathin nanofibers (average diameter 54 nm) are developed by blending low molecular weight polycaprolactone (PCL) with a charged polymer. The resulting nanofibers are cytocompatible, and promote fibrinogen adsorption, platelet adhesion, and activation. Ultrathin nanofibers are coated over gauge to prepare an improved hemostatic product with superior blood and plasma clotting kinetics in vitro and reduced clotting time in vivo.

Abstract

Timely control of bleeding is crucial to reduce mortality in traumatic injuries, highlighting the urgent need for biomaterials with anti-hemorrhagic properties. Polycaprolactone (PCL) is commonly used for producing nanofibers in the range of 100–200 nm. However, creating ultrafine PCL nanofibers with diameters below 100 nm remains a challenge, limiting its potential as a hemostatic bandage. In this study, various ratios of low molecular weight PCL are blended with reduced keratin to modulate the solution shear-thinning behavior. The optimized blend enables the production of ultrafine nanofibers with a mean diameter of ≈50 nm, providing a high surface area. The surfaces of these nanofibers demonstrate excellent platelet adhesion, aggregation, and activation. Additionally, they are cytocompatible with fibroblasts. The ultrathin nanofibers are electrospun on gauze to create a hemostatic product that shows favorable plasma and blood clotting kinetics. An in vivo study demonstrates reduced clotting times for nanofiber-based products compared to plain gauze. Mechanistically, the RBCs on the nanofiber composites attain a polyhedral shape reducing the space between them and creating a compact seal to prevent fresh blood from oozing out. The intrinsic hemostatic properties of keratin, combined with reduced fiber diameter and the hydrophilic nature of gauge make this a promising hemostatic bandage.