PLATELET-LIKE NANOPARTICLES ENHANCE NATURAL WOUND HEMOSTASIS

Synthetic, Bio-compatible Platelets Aid Wound Closure

Researchers from University of California Santa Barbara and Case Western Reserve University have developed platelet-like nanoparticles (PLNs) that act like natural platelets when injected near an open wound. Severe bleeding can be difficult to control in spite of blood’s natural ability to coagulate, as there are often too few platelets to aggregate quickly enough to initiate hemostasis. These synthetic platelets not only signal natural platelets to aggregate and reduce bleeding, but have the same shape and elasticity, allowing them to form part of scars or be metabolized by the body. Their similarity to natural cells also means that the use of synthetic platelets preserves the purity of bodily fluids.

According to the study abstract appearing in ACS Nano, PLNs imitate four main qualities of platelets: discoidal morphology, mechanical flexibility, biophysically and biochemically mediated aggregation, and heteromultivalent presentation of ligands that mediate adhesion to both von Willebrand Factor and collagen, as well as specific clustering to activated platelets. Under physiological flow conditions in vitro, PLNs exhibit enhanced surface-binding compared to spherical and rigid discoidal counterparts and site-selective adhesive and platelet-aggregatory properties. PLNs accumulate at the wound site and reduce bleeding time by ∼65%, effectively mimicking and improving the hemostatic functions of natural platelets as shown by in vivo studies in a mouse model. Potential applications in injectable synthetic hemostats and vascularly targeted payload delivery result from the integration of platelet-mimetic biophysical and biochemical properties of PLNs.