What is electrospinning and what is it used for?
Science and technology are advancing at the speed of light, increasingly offering new and better solutions to everyday problems, and a good example of this is electrospinning technology. Electrospinning equipment allows to obtain fibers by means of coaxial stretching of a viscoelastic solution. These fibers have diameters ranging from sub microns to nanometers, ranges in which it is possible to find unique characteristics such as an very large surface area in relation to volume (in the case of nanofibres, this ratio can be very high, an approximate of 103 times more than a microfiber), flexibility on the surface, high porosity, interconnected pores and superior mechanical performance compared to other already known forms of the material. These characteristics turn nanofibers into optimal candidates for a variety of applications including: fabric engineering, textiles and various medical applications such as bone replacement, dental implants, drug delivery systems, vascular grafts, or artificial blood vessels among others.
The technique consists of rotating polymer solutions through high electric fields inside an electrospinning machine. This technique is based on applying sufficient electric forces that exceed the forces of surface tension in the loaded polymer solution, thus at a given voltage, fine jets of solution are expelled from the capillary to the collector plate. The jet then moves in the direction of the electric field, elongating according to external and internal forces and sometimes experiencing instability. The solvent evaporates and the segments of fibers are randomly deposited on a substrate.
Electrospinning is finding multiple applications from simple laboratory devices to larger, industrial elements, with the use of biomaterials in medicine being the most popular so far. Membranes resistant to biochemical gases or effective in trapping aerosols is another of the electrospinning most advanced uses, as well as in photovoltaic devices, sensors or as covers for electromagnetic protection.
Finally, one of the many modifications that has gained popularity is coaxial electrospinning, which allows two different materials to be spun at the same time. Thus, structures in which one material is surrounded or protected by another can be obtained, and it is possible to isolate one that is unstable in conditions of use with another that is more stable in order to dose the output of the one that is protected in pharmacological applications or to increase the possibilities as a support in tissue engineering when a less biocompatible polymer is surrounded by another one with better characteristics.