Study Of The Proteins Adsorption On PEU/LCP Composite Biomaterial Surface

In clinical medicine, there are many medical devices which must contact with blood. Coagulation occurred on the interface of the medical devices soon after contacted with blood, which subsequently following the protein adsorption, platelets adhesion and activation, and thrombus formation finally.Protein adsorption is the first phase of the whole blood coagulation process. The composition of this protein layer determines the degree to which platelets will be bound and activated. So, protein adsorption research remain focus of biocompatibility of biomaterials development. Poly(ether-urethane) was selected for original material to design good biocompatibility anticoagulant material-PEU/LCP composite biomaterial. It was proved to possess excellent anticoagulant properties. So the study on protein adsorption on its surface and the application of the results of its property to guide our research is critical in anticoagulant biomaterials development.We study the protein adsorption on PEU/LCP composite biomaterial surface by labeled protein with fluorescein isothiocyanate (FITC). The main works and conclusions obtained as follows:(1) Study on the property of new composite material: Firstly, the anticoagulation of PEU/LCP has been investigated. The results of recalcification time test showed that recalcification time of PEU/LCP was 3 times more than that of original material PEU and almost 2 times longer than that of functional PVC. The surface free energy of PEU/LCP is 62.64×10-3J/m2, PVC is 56.89×10-3J/m2, PEU is 41.28×10-3J/m2.(2) Establish the quantitive fluorimetry: Bovine serum albumin (BSA) and fibrinogen (Fg) was successfully labeled with FITC. We have studied the molar ratio of FITC to BSA/Fg in reactions. The effect of labeled BSA/Fg and different ratio of labelled BSA/Fg were also investigated. The result indicated the labeled protein were stable.(3) Study on protein adsorption under static condition: In unitary BSA adsorption experiment, it is demonstrated that the amount of the adsorbed BSA on PEU/LCP surface is more than that of PVC and PEU. Moreover, the amount of adsorbed proteins increases further with the initial protein concentrations. It was found that the quantity of Fg adsorbed on PEU/LCP surface less than the other two materials, and PEU surface adsorbed the most Fg.