Nanocomposites in 3D Bioprinting for Engineering Conductive and Stimuli‐Responsive Constructs Mimicking Electrically Sensitive Tissue

Abstract

Additive manufacturing (AM) using computer-assisted layer-bylayer material deposition is becoming an influential field in biological engineering and regenerative medicine. It holds the potential to regenerate or replace damaged tissue in order to help overcome organ failures and organ scarcity. In bio AM or biofabrication, biological material is deposited three dimensionally in a precise and efficient way. Custom-designed shapes, patterns, and architecture can be prepared, replicating biological tissue-level architecture. For biological engineering, a hydrogel is printed either with or without encapsulated cells. These hydrogels are a network of hydrophilic polymers, able to swell in water like the native tissue extracellular matrix (ECM), [1][2][3] and are the basic building blocks of defined 3D structures. Printed material composed of hydrogel with cells, is called bio-ink. But the cells do not necessarily have to be encapsulated before printing the construct. For a functional biofabricated 3D construct, cells can be seeded or grown into a previously printed design. [4] 3D bioprinting uses several technical solutions to print a defined pattern. Commonly used techniques are bioblotting (i.e., direct extrusion printing, direct dispensing), ink-jet printing, melt electro writing (MEW), solution electro writing (SEW), and electrospinning. Less commonly used or yet emerging techniques in bioprinting, are photo-curing 3D printing techniques like stereo lithography appearance (SLA), digital light processing (DLP), multijet printing (MJP),

Recent Development of Conductive Hydrogels for Tissue Engineering: Review and Perspective

“…In particular, it is unclear how conductive scaffolds interact with biological tissues and propagate signals. [ 181,182 ] Currently, there are also some studies discussing the relationship between the interaction between conductive scaffolds and cells by establishing an interface model. [ 179,183 ] However, other report suggests that these models might only be partially correct.…”

Multifunctional Magnetic Nanoparticles for Dynamic Imaging and Therapy

“…Among diverse stimuli [ 21,22 ] that can be applied to modulate material properties (e.g., magnetic field, [ 23 ] chemical signals, [ 24–27 ] ultrasound, [ 28 ] and photons [ 29–32 ] ), magnetic field has been harnessed intensively in the clinics due to its high tissue nonabsorbable, biocompatible, and imageable characteristics in vivo. [ 33,34 ] Specifically, magnetic fields are utilized to control multifunctional MNPs within the body for versatile biomedical applications.…”

Towards a Novel Cost-Effective and Versatile Bioink for 3D-Bioprinting in Tissue Engineering

“…Most advances focus on increasing print resolution and guaranteeing shape fidelity and cell viability, with more versatile hydrogel formulations able to close the gap between hydrogels and natural cell environments [ 6 ]. Tuning such hydrogel properties can facilitate cell adherence and infiltration into printed structures, leading to tissue remodeling and regeneration into fully functional recovery of injured tissue [ 7 ]. Moreover the porosity of the hydrogel architecture allows improved cell-cell contact, better cell-matrix interaction and higher cell densities compared to non-porous structures [ 8 , 9 ], while simultaneously enhancing nutrient, oxygen and waste diffusion as well as better blood vessel ingrowth.…”