Mussel-inspired degradable antibacterial polydopamine/silica nanoparticle for rapid hemostasis.

High-performance hemostasis becomes increasingly essential in civilian and military trauma. However, available topical hemostats still exist various drawbacks and side-effects. Herein, a silica nanoparticle coated with polydopamine (PDA/SiNP) with good degradability, antibacterial performance was developed for hemorrhage control. PDA/SiNP formed a porous network via lyophilization and rendered material with phenol hydroxyls, aminos, proper hydrophobicity, promising for further cells aggregation and inducing clotting. The degradation behaviors in vitro indicated that the weight loss of PDA/SiNP could attain approximately 40% just after 24 h. All results demonstrated that clotting time of blood was shortened by nearly 150 s for PDA/SiNP compared with that of commercial Celox in vitro hemostasis. PDA/SiNP could significantly accelerate coagulation by activating the extrinsic pathway of the coagulation cascade, adhering platelets and aggregating erythrocytes. Therefore, not only the PDA/SiNP achieved adequate hemostasis with low exothermic effects, but also blood loss was remarkably reduced in the femoral artery and vein injury, liver injury models. Importantly, PDA/SiNP exhibited long-lasting inhibition of Escherichia coli even after 208 h. Also, the hemolysis of PDA/SiNP with low cytotoxicity was much lower, while erythrocytes maintained regular morphology. Thus, amorphous nanoscale PDA/SiNP provided a new avenue for design of silica hemostats and nonmetallic ion antimicrobial.