Design parameters for electrospun biodegradable vascular grafts

Abstract

The inadequacies of the currently used small diameter, non-biodegradable synthetic grafts prompt researchers to focus on the design parameters of vascular grafts. Since the purpose is to mimic the native vessel as far as possible, the design parameters are mainly determined by the layout of cell types and proteins in the layers of the vessels and the nano and micro structure of their environments. In consequence of this, the complex structure of native vessels has become a broad source of inspiration for researchers. Electrospun fibrous scaffolds with their well accepted advantages are promising candidates and researchers are able to work with various materials with differing forms, structures, dimensions, and surface modifications according to their requirements. On the other hand, both synthetic biodegradable polymers and natural proteins are the key materials that enable researchers to take one step closer to achieving the goal of creating an autologous vessel at some time after implantation. When the priority and significance of the need for small diameter vascular grafts is considered, the research field to improve vascular grafts is worthy of note. In this regard, the objective of this review is to discuss comparatively the current studies on the design parameters of electrospun vascular grafts, defined as fiber orientation, fiber diameter, pore size and porosity, wall thickness, and material selection, based on the structure of native blood vessels, the requirements of vascular grafts and electrospinning technology, and the advantages of electrospun vascular grafts, to give an outlook for further studies.

Mechanical investigation of bilayer vascular grafts electrospun from aliphatic polyesters

“…Because PLC fibers are extremely elastic, they cover themselves easily in oriented samples after production, which results in fiber diameter increase. On the other hand, as stated design parameters for vascular grafts in the literature, polymer type and thickness of fiber orientation have crucial effect on tensile strength and elongation at break results. Tensile strength of PCL45_O, PCL80_O, and PLC_O samples (2.2 MPa, 6.7 MPa, and 3.1 MPa) tested in radial direction reaches the maximum values of the same polymer type.…”

Polymer-Based Electrospun Nanofibers for Biomedical Applications

“…These diseases involve inflammatory, infraction, failure, coronary, and stroke. In this respect, electrospun nanofibers can be employed as biodegradable vascular grafts [ 125 ]. Of these, Bertram et al [ 126 ] prepared PCL-based nanofibers integrated with collagen for vascular tissue applications.…”

“…Fibrous collagen protein produces the major morphological matrix [ 128 ]. Mechanically, the organic matrix offers elasticity, while the inorganic crystals provide hardness, thereby contributing to a tough and strong ECM [ 125 ]. It is noteworthy to mention that bone acts as a storage candidate for phosphate and calcium.…”

Structure–property relationship and controlled drug release from multiphasic electrospun carvacrol-embedded polylactic acid/polyethylene glycol and polylactic acid/polyethylene oxide nanofiber mats

“…Electrospinning is an emerging processing technique that allows fabricating non-woven mats composed of continuous fibers exhibiting diameters ranging from micro- to nano-meters [1–5]. The increasing interest in electrospun micro/nanofibrous membranes is due to their high porosity, specific surface, as well as due to tunable mechanical properties and topological features [6–13].…”