Functionally graded electrospun scaffolds with tunable mechanical properties for vascular tissue regeneration

Area of Science:

• Biomaterials Science
• Tissue Engineering
• Polymer Science

Background:

• Vascular tissue engineering requires scaffolds that mimic native artery structure and mechanical properties.
• Polyglyconate (Maxon) and protein blends offer potential for creating biocompatible and mechanically suitable vascular grafts.
• Developing multilayered scaffolds is crucial for replicating the complex architecture of natural arteries.

Purpose of the Study:

• To prepare electrospun tubular scaffolds with a multilayered structure using bio-artificial blends of polyglyconate (Maxon) and proteins (gelatin, elastin).
• To characterize the morphology, structure, and mechanical properties of these novel vascular tissue scaffolds.
• To evaluate the potential of these scaffolds for vascular tissue engineering applications by comparing their properties to native artery tissue.

Main Methods:

• Electrospinning of polyglyconate (Maxon) and protein blends (gelatin, elastin) to create tubular scaffolds with a spatially designed multilayer structure.
• Scanning electron microscopy (SEM) for analyzing scaffold morphology and fiber diameter.
• Fourier-transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), and differential scanning calorimetry (DSC) for compositional and structural analysis.
• Uniaxial tensile testing under dry and wet conditions to determine mechanical properties (tensile strength, modulus, failure strain).

Main Results:

• Scaffolds exhibited a random nanofibrous morphology (200-400 nm fiber diameter) mimicking collagen.
• High interconnected pore structure and porosity (up to 82%) were achieved with protein blending and multi-layering.
• Pure Maxon scaffolds showed high tensile strength (14.46 MPa) and modulus (15.44 MPa).
• Protein blending generally decreased tensile properties, but the gelatin/Maxon scaffold showed an increased tensile modulus (48.38 MPa).
• Trilayered scaffolds (GE-GEM-GM) tested under wet conditions demonstrated mechanical properties (2.5 MPa tensile strength, 9 MPa tensile modulus) comparable to native femoral artery.

Conclusions:

• Multilayered electrospun scaffolds composed of polyglyconate and protein blends can be successfully fabricated.
• These scaffolds possess structural and mechanical characteristics suitable for vascular tissue engineering.
• The developed scaffolds show promise as potential replacements for damaged or diseased vascular tissues, particularly given their comparable properties to native arteries under physiological conditions.