Electrospun amine-modified polysuccinimide/polycaprolactone nanofiber hydrogel dressings as antibacterial and hemostatic wound dressing applications

Design and construction of novel dressings with appropriate structure and multiple bio-functions are urgently required for the wound treatment applications. In this study, a series of wound dressings composed of amine-modified polysuccinimide (PSI)/polycaprolactone (PCL) hydrogel nanofibers were fabricated by using the conjugated electrospinning and the chemical crosslinking post-treatment. All the dressings with different PSI/PCL ratios could effectively maintain the fibrous morphology even after the chemical crosslinking process. The ultimate stress and Young's modulus of the PSI-NH 2 /PCL dressings significantly increased with higher PCL content. In particular, when the proportion of PCL reached 40 % (with a PSI/PCL mass ratio of 60/40), the PSI-NH 2 /PCL dressing exhibited the most excellent mechanical properties, with a Young's modulus of 31.9 ± 8.9 MPa and an ultimate stress of 7.4 ± 0.4 MPa, which were significantly higher than the other samples. Furthermore, all samples exhibited a high swelling ratio of over 350 %, although a noticeable decrease in swelling properties was observed when the content of PCL increased. In addition, all the PSI-NH 2 /PCL dressings showed a high antibacterial activity (> 99 %) against both Escherichia coli ( E. coli ) and Staphylococcus aureus ( S. aureus ), which demonstrated that the addition of PCL has no significant influence on the antibacterial activity of the PSI. Moreover, all the PSI-NH 2 /PCL nanofiber hydrogel dressings had excellent biocompatibility to human dermal fibroblasts (HDFs). Importantly, all the PSI-NH 2 /PCL nanofiber hydrogel dressings presented excellent hemostatic capacity. Notably, even the dressing with the highest PCL content still demonstrated a 71.8 % reduction in bleeding compared to the control group. In summary, our PSI-NH 2 /PCL nanofiber hydrogel dressings with high absorption, biocompatibility and extracellular matrix (ECM)-mimicking capacities, as well as great mechanical, antibacterial, and hemostatic properties are excellent as a promising wound dressing.