Polydopamine reinforced hemostasis of a graphene oxide sponge via enhanced platelet stimulation.

Graphene oxide (GO) is a promising hemostatic material because of its platelet stimulatory activity. However, our previous studies on cross-linked graphene sponges demonstrated that those sponges lost the GO function of platelet stimulation due to the pristine GO was reduced under the harsh reaction conditions. Accordingly, a mild cross-linking strategy is expected to preserve the oxygen-containing groups to further increase the hemostatic performance of the sponges. Here, we present a polydopamine (PDA) cross-linked GO sponge (DCGO) by using mild and facile wet chemistry. The obtained DCGO possessed a high surface charge (-31.3 ± 0.3 mV) and showed strong platelet stimulation. Moreover, this method strengthened the mechanical properties of the DCGO, which supported 350 times its own weight without deformation, thus ensuring its absorbability. For the synergy of platelet stimulation and physical absorption, DCGO achieved outstanding hemostatic performance. Bleeding stopped within 105 ± 15 s, which was 165 s faster than that of the un-cross-linked GO aerogel and 96 s faster than that of the cross-linked graphene sponge (CGS). The DCGO combines the advantages of both PDA and GO, thus supplying a new material and method for the field of trauma hemostasis.