Magnetic-Assisted Cell Alignment within a Magnetic Nanoparticle-Decorated Reduced Graphene Oxide/Collagen 3D Nanocomposite Hydrogel

Abstract

Hydrogel scaffolds are particularly interesting for applications in tissue engineering because of their ability to create a favorable environment which mimics in vivo conditions. However, the hierarchically ordered anisotropic structure which is found in many native tissues and cellular components is hard to achieve in 3D scaffolds. In this work, we report the incorporation of magnetic nanoparticle-decorated reduced graphene oxide (m-rGO) within a collagen hydrogel. This magneto-responsive m-rGO aligned within the collagen hydrogel during gelation with the application of a low external magnetic field. This nanocomposite hydrogel with magnetically aligned m-rGO flakes is capable of encapsulating neuroblastoma cells (SH-SY5Y), promoting cell differentiation and inducing oriented cell growth owing to its excellent biocompatibility and electrical conductivity. The directionally oriented and differentiated SH-SY5Y cells within the m-rGO collagen hydrogel showed propagation of calcium signal along the direction of orientation. This method can be applied to creating magnetically responsive materials with potential for various biomedical applications.

Stimuli‐Responsive Nanocomposite Hydrogels for Biomedical Applications

“…[ 163 ] Concerning this, several studies have successfully demonstrated that magnetic nanoparticles embedded in collagen‐based bioinks/hydrogels could unidirectionally align collagen fibers upon magnetic stimulation, resulting in overall improved mechanical compressive strength, as well as directing cell orientation which dramatically promotes a myriad of cell activities (i.e., enhanced extracellular matrix production, biochemical signal propagation, myo‐ and neurogenesis). [ 165,166 ] Magnetic nanoparticles have also been employed for loading bioactive molecules (i.e., BMP‐2) and for establishing complex biochemical gradients in cell‐laden hydrogels under the influence of magnetic fields, as a strategy to build up osteochondral interfaces that better resemble the growth factor gradients present in the native tissues. [ 22 ]…”

Amino Acid Assisted One‐Pot Green Synthesis of N‐Doped 3D Graphene for Ultrasensitive Neurochemical Sensing

“…It is clearly evident that 3D structure is formed by transparent two-dimensional sheets structure. [35] As shown in the TEM image ( Figure 1C), the GO stacked toghter forming cube shape, showing the existence of layers of graphene oxide. The AFM and height images (Figure 2D) of GO demonstrated that it contains with sharp edges and the thickness of approximately 0.8-1.2 nm.…”

Emerging Neuroblastoma 3D In Vitro Models for Pre-Clinical Assessments

“…Although they do not allow tumor-like 3D cell organization entirely, these scaffolds open an opportunity for a fast and highly reproducible validation of anti-cancer drugs oriented toward the modulation of cell migration. Another application of graphene is in the fabrication of nanocomposite hydrogel scaffolds in which the magnetic nanoparticle-decorated reduced-graphene oxide (m-rGO) nanosheets lead to a unidirectional orientation of the cells (62). This approach is particularly interesting in the models where both cell orientation and the conductivity of the biomaterials are required (63).…”