Mechanically Robust Electrospun Hydrogel Scaffolds Crosslinked via Supramolecular Interactions

Zhang

Macromolecular Bioscience

et al. 2017

Electrospun natural-synthetic composite nanofibers, which possess favorable biological and mechanical properties, have gained widespread attention in tissue engineering. However, the development of biomimetic nanofibers of hybrids remains a huge challenge due to phase separation of the polymer blends. Here, aqueous sodium hydroxide (NaOH) solution is proposed to modulate the miscibility of a representative natural-synthetic hybrid of gelatin (GT) and polycaprolactone (PCL) for electrospinning homogeneous composite nanofibers. Alkali-doped GT/PCL solutions and nanofibers examined at macroscopic, microscopic, and internal molecular levels demonstrate appropriate miscibility of GT and PCL after introducing the alkali dopant. Particularly, homogeneous GT/PCL nanofibers with smooth surface and uniform diameter are obtained when aqueous NaOH solution with a concentration of 10 m is used. The fibers become more hydrophilic and possess improved mechanical properties both in dry and wet conditions. Moreover, biocompatibility experiments show that stem cells adhere to and proliferate better on the alkali-modified nanofibers than the untreated one. This study provides a facile and effective approach to solve the phase separation issue of the synthetic-natural hybrid GT/PCL and establishes a correlation of compositionally and morphologically homogeneous composite nanofibers with respect to cell responses.

Section: Resultsmentioning

confidence: 99%

Alkali‐Mediated Miscibility of Gelatin/Polycaprolactone for Electrospinning Homogeneous Composite Nanofibers for Tissue Scaffolding

Zhang

Macromolecular Bioscience

et al. 2017

“…Furthermore, a UPy-PEG/gelatin blend was processable with electrospinning and the resulting mesh supported growth of a healthy monolayer of kidney epithelial cells. 21,22 Co-axial electrospinning makes use of double or triple 23 concentric nozzles for fabricating core-shell fibers, thereby being identified as an excellent processing technique for the creation of porous networks with hybrid material properties 24,25 and encapsulation of active substances. [26][27][28] Coaxial electrospinning can be used to process solutions which would not be suitable for single-fluid electrospinning, thereby expanding the range of materials processable into fibers.…”

Section: Introductionmentioning

confidence: 99%

Multi-component supramolecular fibers with elastomeric properties and controlled drug release

et al. 2020

Self Cite

ACS Appl. Mater. Interfaces

“…The mass loss of each type of hybrid scaffolds upon the collagenase-supplemented PBS immersion treatment was determined for investigating the degradation behaviors. GelMA, in the hybrid scaffolds, was degraded by the collagenase owing to the presence of MMP-sensitive sites . And PCL was degraded due to the hydrolysis of ester linkages in the backbone .…”

Section: Resultsmentioning

confidence: 99%

“…For electrospun vascular grafts, physicochemical properties and bioactivity are dominant factors affecting their performance for endothelium remodeling . In view of the fact that electrospun hydrogel scaffolds exhibit high water content and excellent water permeability resembling the physiochemical properties of ECM, , as well as biomimetic nanofibrous architecture, , they could be potentially excellent candidates for promoting endothelium remodeling. Particularly, the nanofibrous hydrogel scaffolds made of a photo-cross-linkable naturally derived gelatin methacrylamide (GelMA) have showed superior bioactivity and cell infiltrative properties due to the fact that they contain both the arginine–glycine–aspartic acid (RGD) domain for integrin-mediated cell adhesion and the matrix metalloproteinase (MMP)-sensitive degradation sites for cell-mediated degradation. − This greatly facilitates cell ingrowth and the formation of tissuelike cell-laden constructs for regenerative medicine. , Furthermore, compared to other chemically cross-linked electrospun gelatin scaffolds, , the electrospun GelMA scaffolds by photo-cross-linking display better preserved nanofibrous architecture with good structural stability at aqueous environment and negligible cytotoxicity.…”

Section: Introductionmentioning

confidence: 99%

Regulation Effects of Biomimetic Hybrid Scaffolds on Vascular Endothelium Remodeling

Zhao

Cui

Wang

et al. 2018

The formation of complete and well-functioning endothelium is critical for the success of tissue-engineered vascular grafts yet remaining a fundamental challenge. Endothelium remodeling onto the lumen of tissue-engineered vascular grafts is affected by their topographical, mechanical, and biochemical characteristics. For meeting multiple requirements, composite strategies have recently emerged for fabricating hybrid scaffolds, where the integrated properties are tuned by varying their compositions. However, the underlying principle how the integrated properties of hybrid scaffolds regulate vascular endothelium remodeling remains unclear. To uncover the regulation effects of hybrid scaffolds on vascular endothelium remodeling, we prepared different biomimetic hybrid scaffolds using gelatin methacrylamide (GelMA) and poly-ε-caprolactone (PCL) and then investigated vascular endothelial cell responses on them. GelMA and PCL, respectively, conferred the resulting scaffolds with biomimetic bioactivity and mechanical properties, which were tuned by varying GelMA/PCL mass ratios (3:1, 1:1, or 1:3). On different GelMA/PCL hybrid scaffolds, distinct vascular endothelial cell responses were observed. Firm cell-scaffold/cell-cell interactions were rapidly established on the hybrid scaffolds with the highest mass ratio of bioactive GelMA. However, they were mechanically insufficient as vascular grafts. On the contrary, the scaffolds with the highest mass ratio of PCL showed significantly reinforced mechanical properties but poor biological performance. Between the two extremes, the scaffolds with the same GelMA/PCL mass ratio balanced the pros and cons of two materials. Therefore, they could meet the mechanical requirements of vascular grafts and support the early-stage vascular endothelial cell remodeling by appropriate biological signaling and mechanotransduction. This investigation experimentally proves that scaffold bioactivity is the dominant factor affecting vascular endothelial cell adhesion and remodeling, whereas mechanical properties are crucial factors for the integrity of endothelium. This work offers a universal design strategy for desirable vascular grafts for improved endothelium remodeling.