A Brief Review on Fabrication of Three-dimensional Porous Scaffolds by Electrospinning-Part I: Physical Methods

Nanofiber scaffolds possess high surface-to-volume ratios and adjustable porosity which promotes cellular activities such as attachment and infiltration, therefore providing some key characteristics of the native extracellular matrix. Compared to other production methods of nanofibers, electrospinning is a versatile and simple procedure. Due to recent developments and improvements, electrospinning is becoming a popular technique in the fabrication of three-dimensional (3D) scaffolds. In general, 3D scaffolds can provide a better link between single cells and organs than conventional 2D scaffolds. To date, several approaches have been proposed to fabricate 3D fiber structures by electrospinning. This article summarizes the production of 3D scaffolds using electrospinning techniques by physical methods including combining rapid prototyping and direct-write with electrospinning, post-processing after electrospinning (laser process, physical punching method), liquid-assisted collection, template-assisted collection, porogen-added electrospinning, co-axial electrospinning, and needleless electrospinning. Furthermore, the role of various factors like voltage and humidity in electrospun scaffolds is discussed.