A composition that includes a nanoparticle. The nanoparticle includes a shell which encapsulates sulfated non-anticoagulant heparin (SNACH). The shell includes poly L-arginine. The SNACH is ionically or covalently bonded to the poly L-arginine. A method for treating a disorder of a subject includes: administering to the subject a therapeutically effective amount of the composition for treating the disorder. The disorder is a vascular disorder, a complication of the vascular disorder, or a combination thereof.
