Nanostructured Biomaterials from Electrospun Demineralized Bone Matrix: A Survey of Processing and Crosslinking Strategies

Abstract

In the design of scaffolds for tissue engineering biochemical function and nanoscale features are of particular interest. Natural polymers provide a wealth of biochemical function, but do not have the processability of synthetic polymers, limiting their ability to mimic the hierarchy of structures in the natural extracellular matrix. Thus, they are often combined with synthetic carrier polymers to enable processing. Demineralized bone matrix (DBM), a natural polymer, is allograft bone with inorganic material removed. DBM contains the protein components of bone, which includes adhesion ligands and osteoinductive signals, such as important growth factors. Herein we describe a novel method for tuning the nanostructure of DBM through electrospinning without the use of a carrier polymer. This work surveys solvents and solvent blends for electrospinning DBM. Blends of hexafluoroisopropanol and trifluoroacetic acid are studied in detail. The effects of DBM concentration and dissolution time on solution viscosity are also reported and correlated to observed differences in electrospun fiber morphology. We also present a survey of techniques to stabilize the resultant fibers with respect to aqueous environments. Glutaraldehyde vapor treatment is successful at maintaining both macroscopic and microscopic structure of the electrospun DBM fibers. Finally, we report results from tensile testing of stabilized DBM nanofiber mats, and preliminary evaluation of their cytocompatibility. The DBM nanofiber mats exhibit good cytocompatibility toward human dermal fibroblasts (HDF) in a 4-day culture; neither the electrospun solvents nor the cross-linking results in any measurable residual cytotoxicity toward HDF.

Two‐Phase Electrospinning to Incorporate Polyelectrolyte Complexes and Growth Factors into Electrospun Chitosan Nanofibers

“…Electrospinning is a versatile technique that produces nanofi bers with high porosity and surface area. [59][60][61][62][63] These have some structural and physical properties of the ECM, such as high porosity and surface area. We have previously prepared electrospun fi ber scaffolds and decorated their surfaces with growth factors and with GAG PCNs, using PEMs to form a functionalized porous scaffold.…”

Processed Tissue–Derived Extracellular Matrices: Tailored Platforms Empowering Diverse Therapeutic Applications

“…As with other processing technologies, synthetic polymers are usually more affordable and more convenient to work with, allowing better control and reproducibility, whereas natural materials offer biocompatibility and biomimicry that are crucial for cellular growth and function . A growing number of studies report the utilization of dECM as the base material for the production of electrospun scaffolds for artificial tissue engineering . To allow a stable dECM electrospinning process, the dECM solution should be made spinnable, i.e., to possess certain viscoelastic properties and to denature the protein tertiary chain conformations .…”

Biodegradable and Biocompatible Systems Based on Hydroxyapatite Nanoparticles

“…Diameter size and distribution of fibers was strongly depended on the viscosity of the solution (1,1,1,6,6,6-hexafluoroisopropanol/trifluoroacetic mixture), which increased with the solubilization time ( Figure 3). The process can be performed without the use of a carrier polymer [66] and can take profit of a subsequent treatment with glutaraldehyde vapors to improve mechanical performance. The ultimate strain of the crosslinked sample was 8.85% and the Young's modulus obtained from the linear region of the stress-strain curve 3.37 MPa.…”