Functionalized microgels with fibrin binding elements

Abstract

Ultra-low crosslinked microgels made of an ultra-low crosslinked polymer are provided. The microgels, also referred to as Platelet-like Particles (PLPs), preferably have <0.5% crosslinking densities. One or more of the polymers are conjugated with a fibrin-binding element or moiety, preferably H6, in an amount effective to confer to the microgel selective binding to fibrin under physiological conditions. The PLPs can recapitulate multiple key functions of platelets including binding, stabilizing and enhancing fibrin clot formation, responsiveness to injury cues, and induction of clot contraction. In a preferred embodiment, the microgel or PLP has little or no binding to soluble fibrinogen under physiological conditions compared to its binding to fibrin. The microgels or PLPs are prepared using crosslinker-free synthesis conditions, and can promote or induce clotting and clot contraction.