Improved cell infiltration of highly porous 3D nanofibrous scaffolds formed by combined fiber–fiber charge repulsions and ultra-sonication

Abstract

A significant problem affecting electrospun nanofibrous tissue scaffolds is poor infiltration of cells into their three-dimensional (3D) structure. Environmental and physical manipulation, however, can enhance cellular infiltration into electrospun scaffolds. In this work, RGD-modified alginate mats with increased thickness and porosity were achieved by pairing high humidity electrospinning with post-processing ultra-sonication. RGD-modified alginate, polyethylene oxide (PEO), and an FDA-approved, nonionic surfactant blends were electrospun in 20 and 50% relative humidity conditions. Mats electrospun in high humidity conditions resulted in significantly increased mat thickness and decreased fiber diameters. The mats’ alginate content was then isolated via ionic crosslinking and PEO/surfactant extraction. Finally, the alginate-only mat was post-processed by ultra-sonication to further enhance its cross-sectional thickness. Cell morphology, proliferation, and infiltration into the scaffolds were evaluated by seeding fibroblasts onto the alginate mat. Cell spreading, growth and infiltration improved with increased humidity and ultra-sonication. This approach shows great promise for the design of cell-permeable nanofibrous scaffolds for tissue-engineering applications.

Expanded 3D Nanofiber Scaffolds: Cell Penetration, Neovascularization, and Host Response

“…Kwon and co‐workers exposed 2D poly( l ‐lactide) (PLLA) nanofiber membranes to ultrasonication with different times and obtained 3D nanofiber scaffolds with adjustable pore size and thickness with longer treatment . Alsberg and co‐workers further combined fiber–fiber charge repulsions and ultrasonication to fabricate highly porous alginate nanofiber scaffolds . Unfortunately, most studies have been limited to the fabrication of 3D nanofiber scaffolds composed of random nanofibers and/or certain materials.…”

“…Unfortunately, most studies have been limited to the fabrication of 3D nanofiber scaffolds composed of random nanofibers and/or certain materials. The resultant scaffolds often had insufficient thickness, restricted geometries, and/or uncontrolled porosity . These fabricated scaffolds were also associated with unordered structures and lack of nanotopographic cues that are critical for regeneration of highly organized tissues such as tendon, nerve, and muscle .…”

Delayed Dissolution and Small Molecule Release from Atomic Layer Deposition Coated Electrospun Nanofibers

“…Nanofibers are a unique class of materials which combine many desirable properties, including tunable mat porosity, a high surface area to volume ratio, and controlled surface functionality . These defining characteristics have generated diverse applications for nanofibers in areas ranging from filtration, energy, sensing, packaging, and biotechnology . Additionally, during nanofiber spinning, the fiber matrix can be loaded with molecules or particles to be finely tuned for a desired application.…”

Biomimetic implants for pelvic floor repair

“…Therefore, techniques have been developed to increase pore size in those matrices: the use of sacrificial polymers or space holders that can be dissolved in water, cryo‐spinning with ice particles that melt away after spinning, ultrasonication, and laser cutting. With these techniques, cellular infiltration and maturation of the tissue can be enhanced both in vitro and in vivo …”

“…With these techniques, cellular infiltration and maturation of the tissue can be enhanced both in vitro and in vivo. 62,64,104,[107][108][109][110][111][112][113][114]…”