Wet Electrospinning and its Applications: A Review

Abstract

In wet electrospinning, a natural or synthetic polymer solution is deposited on a non-solvent liquid coagulant used as collector. This technique can create 3D nanofiber scaffolds with better properties (e.g., porosity and high surface area) than those of traditional 2D scaffolds produced by standard electrospinning. Thanks to these characteristics, wet electrospinning can be employed in a wide range of tissue engineering and industrial applications. This review aims to broaden the panorama of this technique, its possible fields of action, and its range of common materials. Moreover, we also discuss its future trends. In this study, we review papers on this method published between 2017 and 2021 to establish the state of the art of wet electrospinning and its most important applications in cardiac, cartilage, hepatic, wound dressing, skin, neural, bone, and skeletal muscle tissue engineering. Additionally, we examine its industrial applications in water purification, air filters, energy, biomedical sensors, and textiles. The main results of this review indicate that 3D scaffolds for tissue engineering applications are biocompatible; mimic the extracellular matrix (ECM); allow stem cell viability and differentiation; and have high porosity, which provides greater cell infiltration compared to 2D scaffolds. Finally, we found that, in industrial applications of wet electrospinning: (1) additives improve the performance of pure polymers; (2) the concentration of the solution influences porosity and fiber packing; (3) flow rate, voltage, and distance modify fiber morphology; (4) the surface tension of the non-solvent coagulant on which the fibers are deposited has an effect on their porosity, compaction, and mechanical properties; and (5) deposition time defines scaffold thickness.

Fabrication of a Triple-Layer Bionic Vascular Scaffold via Hybrid Electrospinning

“…This work applied an innovative wet electrospinning technique to fabricate a precisely aligned tubular scaffold. Unlike conventional wet-electrospinning approaches, which typically yield planar fiber mats [ 43 ], our work presents a modified technique aimed at achieving a specific 3D tubular architecture. Additionally, our innovative wet-electrospinning technique produced aligned fiber arrangements, as opposed to the random arrangement of fibers obtained via conventional wet electrospinning [ 43 ].…”

“…Unlike conventional wet-electrospinning approaches, which typically yield planar fiber mats [ 43 ], our work presents a modified technique aimed at achieving a specific 3D tubular architecture. Additionally, our innovative wet-electrospinning technique produced aligned fiber arrangements, as opposed to the random arrangement of fibers obtained via conventional wet electrospinning [ 43 ]. Wang [ 26 ] also utilized a similar wet-electrospinning method to fabricate an aligned fiber scaffold, but they still fabricated planar fiber mats.…”

Revolutionizing electrospinning: Sustainable solutions through deep eutectic solvents in biopolymer processing

“…This modification involves electrospinning the polymer solution into the collecting bath, either directly into its volume or using an air gap between the needle tip and the liquid surface. 138 In both cases, it is not always necessary to use a solid grounded collector immersed within the bath. As a result of the polymer solution jet entering the coagulation bath during electrospinning, the fibers start to solidify.…”

“…While using a bath with a lower value of surface tension, the fibers will have a better organized 3D structure, resulting in higher porosity and lower apparaent density. 138,143,144 Currently, various types of solvents are used as the coagulation medium in baths, primarily organic solvents (usually methanol, ethanol, or acetone), weak inorganic acids, water or electrolyte solutions. 138,139,145 In the aforementioned work, 46 the researchers used a DES as a solvent for lignin to then electrospin the solution thus prepared to obtain fibers, which were eventually transformed into lignin aerogels.…”

“…138,143,144 Currently, various types of solvents are used as the coagulation medium in baths, primarily organic solvents (usually methanol, ethanol, or acetone), weak inorganic acids, water or electrolyte solutions. 138,139,145 In the aforementioned work, 46 the researchers used a DES as a solvent for lignin to then electrospin the solution thus prepared to obtain fibers, which were eventually transformed into lignin aerogels. Due to the nonvolatile nature of the deep eutectic solvent used, it was necessary to modify the classically used apparatus for the electrospinning process with an additional coagulation bath in the form of deionized water, which allowed the fibers of the electrospun polymer to solidify and flush out the residuals of the original solvent along with the additives.…”