Smart Hydrogels for Bone Reconstruction via Modulating the Microenvironment

Abstract

Rapid and effective repair of injured or diseased bone defects remains a major challenge due to shortages of implants. Smart hydrogels that respond to internal and external stimuli to achieve therapeutic actions in a spatially and temporally controlled manner have recently attracted much attention for bone therapy and regeneration. These hydrogels can be modified by introducing responsive moieties or embedding nanoparticles to increase their capacity for bone repair. Under specific stimuli, smart hydrogels can achieve variable, programmable, and controllable changes on demand to modulate the microenvironment for promoting bone healing. In this review, we highlight the advantages of smart hydrogels and summarize their materials, gelation methods, and properties. Then, we overview the recent advances in developing hydrogels that respond to biochemical signals, electromagnetic energy, and physical stimuli, including single, dual, and multiple types of stimuli, to enable physiological and pathological bone repair by modulating the microenvironment. Then, we discuss the current challenges and future perspectives regarding the clinical translation of smart hydrogels.

Photo‐Controllable Smart Hydrogels for Biomedical Application: A Review

“…[189] PCHs can also be used for bone and cartilage regeneration. [190][191][192][193][194] Qiao et al constructed a co-photocrosslinked GelMA-c-osteoblastic growth peptide hydrogel delivery system that prolonged the osteoblastic activity of osteoblastic growth peptide for maintenance and release after slow degradation and provided an ideal microenvironment for cell adhesion, proliferation and osteoblastic differentiation. [195] Huang et al prepared a hydrogel that could promote the continuous release of phosphate by photopolymerization of GelMA and cationic arginine unsaturated poly (ester amide) [U-Arg-PEA], and encapsulated black phosphorus nanosheet.…”

“…PCHs can also be used for bone and cartilage regeneration. [ 190–194 ] Qiao et al. constructed a co‐photo‐crosslinked GelMA‐c‐osteoblastic growth peptide hydrogel delivery system that prolonged the osteoblastic activity of osteoblastic growth peptide for maintenance and release after slow degradation and provided an ideal microenvironment for cell adhesion, proliferation and osteoblastic differentiation.…”

Advances and Trends of Photoresponsive Hydrogels for Bone Tissue Engineering

“…Compared to other stimuli-responsive hydrogels, photoresponsive hydrogels are unique in several important respects: (1) Light is a safe, noninvasive, easy acquired, and inexpensive stimulus. 35 It can be remotely manipulated with minimal byproducts. (2) Photoresponsive hydrogels enable molecular changes for cargo activation and release in a fully cytocompatible manner using visible light, ultraviolet (UV) light, and nearinfrared (NIR) light.…”

Nano-crosslinked dynamic hydrogels for biomedical applications

“…Hydrogels are a class of polymers characterized by a three-dimensional (3D) network of crosslinked hydrophilic chains. Since hydrogels have a structure and function similar to those of the natural extracellular matrix (ECM), they can be widely used in the biomedical field [ [1] , [2] , [3] , [4] , [5] ] as drug-delivery platforms [ [6] , [7] , [8] , [9] ], wound dressings [ [10] , [11] , [12] , [13] ], and tissue engineering repair materials [ [14] , [15] , [16] , [17] , [18] , [19] , [20] , [21] ]. Although hydrogels exhibit some remarkable properties, they still have many properties, such as a low mechanical strength, poor thermal stability, rapid degradation rate, and no self-healing ability after damage, that limit their biomedical applications.…”