Effect of thrombin conjugation on hemostatic efficacy of PLGA mesh through reagent free surface modification

In this study, thrombin-conjugated PLGA (THR-PLGA) electrospun meshes were prepared through reagent free surface modification based on Schiff base reaction between amine groups in thrombin and carbonyls on the surface of PLGA meshes, and their feasibilities on the improvement of hemostasis were evaluated. In vitro studies were performed with chromogenic substrate and transglutaminase activity assays to evaluate the thrombin activity and FXIIIa activity of the THR-PLGA samples, respectively. A rat tail injury model was employed for measuring hemostatic time of the samples. The results showed that the hemostatic efficacy of the samples increased with increase in the content of THR on the surface of the samples. In addition, partial splenectomy was carried out in rat model to investigate the potential management of hemorrhage of THR-PLGA, as compared to Vicryl® and TachoSil®. The results showed that the inflammatory response was significantly reduced compared to Vicryl® and TachoSil®, and a dense fibrous layer was produced to protect the inside from laceration at 2 weeks of treatment. Moreover, neo pulps were appeared right below the fibrous capsule. These findings suggest that THR-PLGA samples prepared through the reagent free immobilization method deserves further advanced investigations for future clinical applications.