Biocompatibility evaluation of electrospun Poly-L lactic Acid-chitosan immobilized with heparin as scaffold for vascular tissue repair

Stroke is the second leading cause of death worldwide, disability, high morbidity and mortality. One of the leading cause of infarct stroke is carotid stenosis. The postoperative narrowing of the carotid artery diameter is a common complication after primary arterial closure in carotid endarterectomy surgery. A biomaterial design that combines synthetic and natural polymers is a promising strategy to patch arterial closure. In this paper, the electrospinning process was employed and Poly-L Lactic Acid (PLLA) was used as a base material. Chitosan and heparin were added to increase the biocompatibility of the biomaterial. The electrospun PLLA-chitosan immobilized with heparin (C sample) had better characteristics than the pure electrospun PLLA. The fiber diameter decreases to a micrometer scale and the pore size decreased and became narrower, resulting in a smoother surface. Fiber diameter results for each sample were 1312.66 nm, 486.29 nm and 387.87 nm. Thereby potentially reducing the activation of blood coagulation and inflammation. The ultimate tensile strength test result for each sample were 2.28 MPa, 3.61 MPa and 3.25 MPa, for elongation results were 12.05%, 17.39% and 18.14%, aligned with those of human carotid artery and indicating potential use in patch angioplasty applications. This scaffold nanofiber was declared to be non-haemolytic for C sample was 1.13% and non-cytotoxic. Percent viability for each sample were 89.35%, 83.81% and 78.92%. The in vivo host tissue response was shown to decrease pro-inflammatory cytokine expressions. This research shows that the proposed PLLA-chitosan-heparin biomaterial has strong physical properties and can modify the inflammatory response, however it requires additional biofunctional alterations to optimize its tissue engineering capabilities.