Progress in heparin and heparin-like/mimicking polymer-functionalized biomedical membranes

Research into the design of heparin and heparin-like/mimicking polymer-functionalized biomedical membranes is of tremendous interest to the biomedical sector in particular and is driven by potential diverse biomedical applications such as blood purification, artificial organs and other clinical medical devices. In this review, we highlight the progress of the recent research and propose potential biomedical applications in the fields of surface heparinization and the heparin-inspired modification of polymeric membranes. We summarize various surface heparinization strategies such as blending, surface coating, grafting, layer-by-layer assembly and mussel-inspired coating. Then, we classify the heparin-like/mimicking polymers and their applications in the design of heparin-mimicking biomedical membranes and draw some conclusions. The general concept of heparin-like/mimicking polymers is usually defined as heparan sulfates or synthetic sulfated/carboxylated polymers with comparable biologically mimicking functionalities as heparin, especially anticoagulant activity. Moreover, the potential biomedical applications and benefits of heparin and heparin-like/mimicking polymer-functionalized membranes in blood purification, artificial organs and tissue engineering are also discussed in each section. The heparin and heparin-like/mimicking polymer-functionalized membranes presented are exceptional candidates for the treatment of organ failure and many other blood-contacting fields. Finally, we conclude with the challenges and future perspectives for the strategies toward the heparinization and heparin-like/mimicking modification of membrane surfaces. It is believed that this review will evoke more attention towards the design of heparinized and heparin-like/mimicking membranes and encourage future advancements of this emerging research field.