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Perposes:using Polycaprolactone(PCL) as basic material,construct VEGF-BSA/PCL-PEG nanofibers by coaxial electrospinning,and examine the law of the voltage playing influence on the nanofibers diameter and the fibers structure.Material and method:BSA solution and VEGF solution separatly at10mg/ml and10μg/ml in distilled water were used as the core solution and10%w/vPCL in60:40(v/v) dichloromethane ethanol used as the shell solution,BSA was used as Stabilizer solution,PEG was added in the shell at the concentration of0mg,1mg,10mg and20mg per milliter.Then,they were separatly send into two syringes.The flow rate was set at0.5ml/h for the core solution and2ml/h for the shell solution.The optimum flow rate ratio between the shell and core solution was4：1.The voltage gradient was adjusted from15kv to18kv,with theelectrospinning distance fixed at5cm.Then construct VEGF-BSA/PCL-PEG nanofibers by coaxial electrosinning,drid under vacuum oven at room temperature for24hours and stored in the40C refrigerator.Results:examine VEGF-BSA/PCL-PEG nanofibers structur at the voltage from15kv to18kv under Scanning electro microspocy（SEM）and randomly count30nanofibers diameter by the software of Image-J.the results show the nano fibers’ diameter slgiht increased as the voltage increased.Then examine VEGF-BSA/PCL-PEG nanofibers structur at the16kv voltage under transmission electron microscopy（TEM）and observed apparent the core and shell structure.Conclusion:we successfully construct VEGF-BSA/PCL-PEG nanofibers.which can carry VEGF in the core. Purposes: explore the fesibility of the VEGF-BSA/PCL-PEG nanofibers releas-ing VEGF and BSA in vitro and detect the concentration of VEGF andBSA at set time.draw the curve of time-cumulative release percentage and explore the release law. At last,examine the biological activity of VEGF.Material and method: construct BSA/PCL, BSA/PCL-PEG(100/1,m/m)，BSA/PCL-PEG(10/1,m/m),BSA/PCL-PEG(5/1,m/m) nanofibers by coaxial electrospinning,then put the above every5specimens in the6-well plates filled with4ml1×PBS solution.The supernatant was then removed and replenished with fresh PBA solution at predetermined time-1th,3th,7th,15th,30th day.the amount ofBSA present in the supernatant was determined by micro-BCATMprotein assay.Draw the curve of time-cumulative release percentage. VEGF-BSA/PCL-PEG（5：1,m/m）nanofibers releasing VEGF was analyzed by enzyme-linked immunosorbent assay（ELISA） using the same way above. Draw the curve of time-cumulative release percentage of VEGF.At last,adjust the concentration of VEGF released at1th,3th,7th day to1ng/ml,cultivate the1×104endothelial cells,three days later count the cells and calculate cells value-added rate,compared with no-VEGF and fresh VEGF.Results: the BSA of BSA/PCL, BSA/PCL-PEG(100/1,m/m)，BSA/PCL-PEG(10/1,m/m),BSA/PCL-PEG(5/1,m/m) was burst release at the fisrt day.in the30day, cumulative release percentage of the BSA of BSA/PCL was not more than60%,while BSA/PCL-PEG(100/1,m/m)，BSA/PCL-PEG(10/1,m/m),BSA/PCL-PEG(5/1,m/m) more than90%.PEG can accelarate the release. The VEGF of VEGF-BSA/PCL-PEG（5：1,m/m）was released last for30days,in the30days,cumulative release percentage of VEGF was almost98%.The biological activityof the releasing VEGF was not damaged.Conclusion: VEGF-BSA/PCL-PEG nanofibers can release VEGF and BSA for30days, the biological activity of the releasing VEGF was not damaged Objiective:To evaluate the blood compatibility,physical characteristics andBiological activity of the membrane of vegf-coaxial electrospinning In vitro andexplore its feasibility to be as subtitution of artificial cardiovascular materials.Method:The membrane of VEGF-coaxial electrospinning was prepared by thetechnology of coaxial electrospinning,Then,the blood compatibility of the membraneof VEGF-coaxial electrospinning was investigated in terms of hemolysis, dynamicclotting time, thrombin time (TT), prothrombin time (PT), activated partialthromboplastin time (APTT), platelet adhesion, cytotoxicity test and Biologicalactivity, compared with Dacron.Result: The membrane of VEGF-coaxial electrospinning is highly compatiblewith human blood as Dacron,but it is apt to be adhered by Vascular endothelial cells. Conclusion: The membrane of VEGF-coaxial electrospinning is highlycompatible with human blood and is apt to be adhered by Vascular endothelial cells,soit show favorable prospects to be as subtitution of Artificial cardiovascular materials
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