Highly Moldable Electrospun Clay-Like Fluffy Nanofibers for Three-Dimensional Scaffolds

Abstract

The development of three-dimensional polymeric systems capable of mimicking the extracellular matrix is critical for advancing tissue engineering. To achieve these objectives, three-dimensional fibrous scaffolds with "clay"-like properties were successfully developed by coaxially electrospinning polystyrene (PS) and poly(ε-caprolactone) (PCL) and selective leaching. As PS is known to be nonbiodegradable and vulnerable to mechanical stress, PS layers present at the outer surface were removed using a "selective leaching" process. The fibrous PCL scaffolds that remained after the leaching step exhibited highly advantageous characteristics as a tissue engineering scaffold, including moldability (i.e., clay-like), flexibility, and three-dimensional structure (i.e., cotton-like). More so, the "clay-like" PCL fibrous scaffolds could be shaped into any desired form, and the microenvironment within the clay scaffolds was highly favorable for cell expansion both in vitro and in vivo. These "electrospun-clay" scaffolds overcome the current limitations of conventional electrospun, sheet-like scaffolds, which are structurally inflexible. Therefore, this work extends the scope of electrospun fibrous scaffolds toward a variety of tissue engineering applications.

Copolymer/Clay Nanocomposites for Biomedical Applications

“…[ 110 ] Hence, mimicking scaffold composition, morphology, rate of degradation and strength according to the native tissues are key factors during fabrication. [ 111 ] The clay reinforcement in such polymeric scaffolds/membranes provides an additional benefit in terms of mechanical support, thermal stability, reduced degradation time, and improved processability. Additionally, clay reinforced copolymer scaffolds can be stimuli‐responsive, too.…”

“…Various reports for the fabrication of copolymer‐clay scaffolds/membranes and their key features are compiled in Table 4 . [ 65,111,115 ] Wang et al [ 60 ] demonstrated drug laponite nanodisk electrospun nanocomposite scaffolds using poly(lactic‐ co ‐glycolic acid) copolymer with embedded amoxicillin. The nanocomposite scaffolds showed good drug loading efficiency, sustained drug release characteristics, and antimicrobial properties without compromising their cell compatibility.…”

Polymers in Tissue Engineering

“…This creates a dense, isotropic (all-directional), mat of fibers. This structure tends to lack space between the fibers, and important feature if cell migration into the material is desired, but strategies such as adding dissolvable fibers [18,19], leaching inorganic salts [20,21] or other particulates [22], or even jets of air [23] at the site of collection mechanically create some space for residents cells on the material to grow into. However, while many human tissues have significant thickness and require a length and depth of cells on an extracellular matrix, it is important to consider that many tissues (such as epithelial cell-based tissue) are single-layered, and a basement membrane which isn't penetrable by cells is important for proper morphology of attached cells [24].…”

Bio-compatible poly(ester-urethane)s based on PEG–PCL–PLLA copolymer with tunable crystallization and bio-degradation properties

“…for vascularized tracheal substitute, 3 bone formation, 4,5 cartilage regeneration matrix, 6 and so on. 8 Numerous studies were mainly focused on technical level, modication via blending by electrospinning technique, [9][10][11][12][13] surface modication of electrospun membranes 14,15 or other technics. Generally, pure PCL or PLLA can't meet the functional requirements well.…”