Electrospun Polycaprolactone Scaffolds Using an Ionic Liquid as Alternative Solvent: Morphometric, Mechanical and Biological Properties

Abstract

Ionic liquids (IL) are a greener alternative to aggressive organic solvents used for biopolymers dissolution in the electrospinning process. Nevertheless, the effect of IL on the properties of the electrospun materials is still a gap. In this work, we obtain polycaprolactone (PCL) electrospun mats using two solvents, either trichloromethane (CHCl 3)-a conventional toxic and carcinogenic solvent-or 1-butyl-3-methylimidazolium chloride ([Bmim]Cl), an ionic liquid. The differences between the respective electrospun products were assessed through the scaffold's morphology, mechanical properties and cytotoxicity. The use of IL resulted in the formation of textured thinner fibers, enhancing the surface area in 43 %. IL induced a lower rupture stress and elongation of the mats of 34 and 39 %, respectively, while the elastic modulus and yield stress did not present significant differences. The cytotoxicity assays using L929 cells detected a number of viable cells slightly higher for the scaffold produced with IL. Cell interaction tests also revealed that L929 cells adhere and proliferate on both scaffolds. However, the cell adhesion was higher for the mats fabricated using IL. Beyond the results, this work sheds light on the pros and cons of tissue engineering scaffolds produced with the aid of less hazardous solvents.

The Drug-Loaded Electrospun Poly(ε-Caprolactone) Mats for Therapeutic Application

“…In addition, smooth defect-free nanofibers with a narrow and more uniform diameter distribution are collected using two-component solvent systems. There have already been various solvents used, including benign or green, to prepare the PCL solutions for electrospinning, such as acetone, methanol, formic or acetic acid, or ionic liquids [ 47 , 48 , 49 ]. However, in these solvents it is not possible to achieve the required fiber characteristics (smoothness, small average diameter, uniform); therefore, in the conducted study, the solutions for electrospinning were prepared using a mixture with DCM as a good solvent for PCL.…”

Preparations and Properties of Ionic Liquid-Assisted Electrospun Biodegradable Polymer Fibers

“…Additionally, [C 2 mim][OAc] is the main ionic liquid utilized as a solvent, followed by 3 that cellulose, silk, and chitin were mostly dissolved in ionic liquids, compared to other natural biodegradable polymers. In addition, synthetic biodegradable polymers, such as PCL and PLA can be dissolved in ionic liquids [4,29]. This proved that the ionic liquids could not only be utilized for dissolving natural polymers but also synthetic polymers.…”

“…Figure 1 exhibits the chemical structures of cellulose, cellulose acetate, chitin, and chitosan. Besides this, it can also be seen in Table 1 that synthetic biodegradable polymers, for example, polyhydroxybutyrate (PHB); polycaprolactone (PCL); polylactic acid (PLA); and polyvinyl alcohol (PVA) can be employed for the preparation of electrospun fibers [3,4,29,34]. Moreover, previous studies have shown that natural-synthetic polymer hybrid fibers have also been prepared via the electrospinning method [29,34].…”

“…Electrospun biodegradable polymer fibers have become an attractive material to investigate because of their biocompatibility, biodegradability, and regenerative properties [2]. Furthermore, the thickness of electrospun fibers can be altered by adjusting the spinning parameters [3], such as the rheological properties of the polymer solution, needle/collector distance, type of collector, and voltage applied [4]. On top of that, there are two types of biodegradable polymers, specifically natural and synthetic polymers.…”

“…This is because cellulose is one of the most abundant biodegradable polymers on the earth. [12,30] Petroleum-based Collagen [19] Polybutylene succinate PBS [31] Ethyl cellulose [32] Polycaprolactone PCL [4] Gelatin [33] Polyvinyl alcohol PVA [34,35] Heparin [13] Silk [19,36,37] Natural waste Starch [34] Polylactic acid PLA [3,29,38,39] Recently, chitin, the second most abundant natural polymer after cellulose [1,29] has also been employed for the preparation of electrospun fibers. In addition, cellulose and chitin derivatives, such as cellulose acetate [24][25][26] and chitosan [12,30] were employed to prepare electrospun fibers.…”