Polyurethane/polycaprolactone membrane grafted with conjugated linoleic acid for artificial vascular graft application

Constructing satisfied small-diameter vascular graft (diameter less than 6 mm) remains an unsolvable challenge in vascular tissue engineering. This study described the fabrication of electrospun polyurethane/polycaprolactone (PU/PCL) membranes chemically grafted with various densities of conjugated linoleic acid (CLA) - an antithrombotic fatty acid - for making small-diameter blood vessel. Differences in mechanical, antithrombotic properties and biocompatibility of the membranes resulting from the CLA-grafting procedure were the focus of the study. Investigation of mechanical properties relevant to vascular graft application revealed that these properties of the membranes remained unaffected and satisfied clinical criteria following the CLA graft. Blood-membrane interaction assays showed that the CLA-grafted membranes mitigated the adhesion of blood cells, as well as preventing blood coagulation. These effects were also commensurate with increasing density of CLA, suggesting an effective approach to improve antithromboticity. Cellular tests suggested that CLA has an optimal density at which it promoted cell proliferation on the surface of the membranes; however, excessive presence of CLA might cause undesirable inhibition on cells. In conclusion, PU/PCL membrane grafted with CLA could be a prospective material for vascular tissue engineering with further development and investigation.