Preparation, blood compatibility and anticoagulant effect of heparin-loaded polyurethane microspheres

Recent advances in micro- and nanotechnology have provided a variety of particles with highly controlled shapes, sizes, chemical composition, and interesting properties. In this work, a novel kind of heparin-functionalized polyurethane microsphere (Hep-PU MS) was synthesized by a single-step phase separation method. The blood compatibility and anticoagulant effect of the Hep-PU MSs were investigated using coagulation tests, hemolysis assay, complement and platelet activation detection, cytotoxicity analysis, and drug loading and release study. The results confirmed that the heparin can substantially enhance the anticoagulant properties of PU MSs, and the Hep-PU MSs have the potential to be used as a mild anticoagulant compared to heparin. With the simplicity of the functionalized method, the excellent hemocompatibility and the slow-release of heparin, the Hep-PU MSs with desirable bioproperties can be readily tailored to cater to various biomedical applications.