Smart Hydrogels in Tissue Engineering and Regenerative Medicine

Abstract

The field of regenerative medicine has tremendous potential for improved treatment outcomes and has been stimulated by advances made in bioengineering over the last few decades. The strategies of engineering tissues and assembling functional constructs that are capable of restoring, retaining, and revitalizing lost tissues and organs have impacted the whole spectrum of medicine and health care. Techniques to combine biomimetic materials, cells, and bioactive molecules play a decisive role in promoting the regeneration of damaged tissues or as therapeutic systems. Hydrogels have been used as one of the most common tissue engineering scaffolds over the past two decades due to their ability to maintain a distinct 3D structure, to provide mechanical support for the cells in the engineered tissues, and to simulate the native extracellular matrix. The high water content of hydrogels can provide an ideal environment for cell survival, and structure which mimics the native tissues. Hydrogel systems have been serving as a supportive matrix for cell immobilization and growth factor delivery. This review outlines a brief description of the properties, structure, synthesis and fabrication methods, applications, and future perspectives of smart hydrogels in tissue engineering.

Self-Assembly of Organic Nanomaterials and Biomaterials: The Bottom-Up Approach for Functional Nanostructures Formation and Advanced Applications

“…Moreover, some stimuli-responsive nanogels are able to perform mechanical work or change its aggregation state in response to changes of external physical properties (stimuli), such as the light or electric field exposure, and its temperature [101]. The hydrosoluble Poly(N-isopropylacrylamide) (PNIPAM), Chitosan, Poy(vinil alcohol), alginate hydrogels are among the most intensely investigated polymer systems for advanced biomedical applications [101,102]. The main applications of stimuli-responsive hydrogels include microactuators and microfluidic devices, electrolyte batteries, artificial muscles and superadsorbents [100][101][102].…”

“…The hydrosoluble Poly(N-isopropylacrylamide) (PNIPAM), Chitosan, Poy(vinil alcohol), alginate hydrogels are among the most intensely investigated polymer systems for advanced biomedical applications [101,102]. The main applications of stimuli-responsive hydrogels include microactuators and microfluidic devices, electrolyte batteries, artificial muscles and superadsorbents [100][101][102]. The pH-responsive gels have been mainly employed for hydrophilic drug delivery.…”

“…The pH-responsive gels are particularly versatile for the targeted drug delivery. In biomedical research, the responsive hydrogels have been found to have applications in the fields of drug delivery, biosensors and bio-mimetic nanomaterials [101,102]. Moreover, hydrogels and nano-gels have been used as versatile tissue engineering scaffolds due to their ability to restore, retain and regenerate the damaged tissues.…”

Design of Bio-Conjugated Hydrogels for Regenerative Medicine Applications: From Polymer Scaffold to Biomolecule Choice

“…In the past decades, one of the most significant challenges faced in regenerative medicine, tissue engineering and in vivo biomedical devices for tissue regeneration was related to the inability to mimic the mechanical properties and dynamic structure of the soft tissue that needed to be repaired or constructed [ 5 ]. Thus, research has been focusing on developing soft materials that: (i) are prone to adapt and resist physiological conditions, satisfying strict requirements for biocompatibility, softness, resistance to mechanical stress and general chemical versatility, (ii) provide the conditions for cell growth, differentiation and proliferation and (iii) degrade naturally or shortly after the healing of the damaged tissue [ 6 , 7 ]. These requirements can be fulfilled by hydrogels, which are cross-linked colloidal networks fully swollen in its entire volume by water if they are based on appropriate chemical nature of their building blocks [ 8 ].…”

Modulation of the secretion of mesenchymal stem cell immunoregulatory factors by hydrolyzed fish collagen

“…With the technological advancement of stem cell and tissue engineering, regenerative medicine has become a hot topic in the field of biological medicine (1). The self-renewal and multidirectional differentiation of stem cells enables them to serve as seed cells for tissue engineering, facilitating the repair of damaged tissues or organs (2).…”