A method for storing and using platelets and an associated platelet structure. At least one modified platelet is formed. Each modified platelet includes a platelet and at least one polymerated chemical. Each polymerated chemical includes a polymer covalently bonded directly to the platelet or includes the polymer and a linker molecule such that the linker molecule is covalently bonded to the platelet and the polymer is covalently attached to the linker molecule. The polymer of each polymerated chemical of each modified platelet is polyethylene glycol (PEG) or a PEG derivative. Forming each modified platelet does not include modifying the platelet membrane of each platelet with a glycan-modifying agent. The at least one modified platelet is stored in a temperature range below 20° C. for at least one hour. After being stored, the at least one modified platelet may be introduced into a mammal.
