Chitin nanowhiskers based on Periplaneta americana residue for preparing deep eutectic solvent (DES)-thrombin bio-adhesive with hemostatic effect.

In this study, chitin nanowhiskers (ChNWs) were extracted and prepared from discarded Periplaneta americana residues after extraction. These ChNWs were used as the polymeric matrix of a new bio-adhesive, while a biocompatible aqueous deep eutectic solvent (DES) served as the system medium. Thrombin (T) was incorporated as the hemostatic agent, and gelatin (G) was added to improve the overall mechanical properties. In above system, the relative activity of thrombin in 30% DES increased to 116.12%. The prepared ChNWs exhibited stable dispersion and crystallinity exceeding 90%, and the adhesive strength of bio-adhesive (ChNWs/G/DES-T) on clean and blood-soaked porcine skin tissue reached 27.31 kPa and 14.24 kPa, respectively, outperforming commercial fibrin glue (7.1 ± 0.8 kPa). Furthermore, the bioadhesive demonstrated strong bonding to various biological tissues as well as organic and inorganic material surfaces. The underlying adhesion mechanisms involved hydrogen bonding, electrostatic interactions, coordination interactions, and van der Waals forces. Compared to the saline control group, it reduced clotting time by 71.12%, surpassing commercially available chitosan hemostatic powders and gel (45.38% and 26.37%, respectively). The hemostatic mechanism was associated with its effective adhesion to platelets and red blood cells. Additionally, it exhibited favorable swelling, degradation, and biocompatibility properties.