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Electrospinning is another technique which is used for the fabrication of cardiovascular scaffolds [29]. Figure 2.2 depicts the schematic representation of the electrospinning process. An electric field is applied as soon as the solution containing a conductive polymer is ejected from the needle and collected on a target. When the solvent dries out, a fibrous network exactly similar to the structure of our body's natural ECM is formed [30]. By adjusting the processing parameters (such as voltage, working distance, flow rate, and temperature) or the polymer solution conditions (such as conductivity, viscosity, and concentration), the structure as well as the diameter of the fiber can be altered [31]. Taking advantage of the synthetic polymers' mechanical strength and natural polymers' biocompatibility, serious efforts have been taken to hybridize these structures. Successful and interesting advancements have been made in the field of heart valve tissue engineering [32]. Under these circumstances, electrospinning technique has been used to develop a biohybrid scaffold, which consists of non–cross‐linked decellularized bovine pericardium ECM coated with an adhesive layer of polycaprolactone (PCL)–chitosan nanofibers [33]. In order to enhance the fiber–polymer interactions, and due to the hydrophobic nature of PCL, it has been blended with a mixture of several materials (dextran, cellulose acetate, polyhydroxybutyrate, and chitosan nanofibers) [34]. Dip coating technique has been used to improve the mechanical properties of the decellularized scaffolds, without the use of cross‐linkers [35]. Even though these dip‐coated scaffolds resulted in having better mechanical properties than electrospinning, the structural integrity of the ECM nanofibers were disrupted with the use of organic solvents. Thus, electrospinning forms the most appropriate choice for processing.

Figure 2.2 Fabrication of electrospun nanofibers under high voltage.