Immobilized heparin and its anti-coagulation effect on polysulfone membrane surface

Abstract

Polysulfone has been widely used as hemodialysis membrane material because of its excellent physiochemical performance. There is still a need to further improve its anti-coagulation property in clinical practice. In this work, we covalently immobilized heparin onto polysulfone membrane to improve its anti-coagulation performance. Low temperature plasma technique with environmentally friendly nitrogen as the gas source, as well as N-ethyl-N′-[3-dimethylaminopropy] carbodiimide hydrochloride/hydroxy-2,5-dioxopyrolidine-3-sulfonicacid sodium chemistry were utilized to immobilize heparin onto the surface of polysulfone membrane. X-ray photoelectron spectroscopy, attenuated total reflectance Fourier-transform infrared spectroscopy, as well as water contact angle results confirmed successful binding of heparin to the membrane surface. Only slight permeability differences were observed between the immobilized surface and the unmodified surface, while the polysulfone membrane had become more hydrophilic after immobilization. The blood coagulation time was greatly prolonged after modification and less platelets adhesion was observed on the heparin immobilized surface. Also, compared with heparin injection doses in clinical, the heparinized process in our work consumed less heparin. Our study suggests that the immobilized heparin has local anti-coagulation effect, while reducing the doses.

Keywords:

• hemodialysis
• polysulfone membrane
• low temperature plasma
• heparin
• immobilization
• anti-coagulation

Acknowledgements

We thank our volunteers who denoted their blood for the coagulation and platelet adhesion test. This work was supported by State Key Development Program for Basic Research of China (Grant 2007CB936103), and the Fundamental Research Funds for the Central Universities.