Self-adaptive hydrogels to mineralization

An on-demand and on-site shape-designable mineralized hydrogel with calcium supply and inflammatory warning properties for cranial repair applications

Although more than 2.2 million cranial repair surgical operations are performed every year, orthopedic doctors still dream of excellent artificial repair materials with suitable strength, on-site and on-demand fast-shaping properties, and bone induction properties. However, fast-shaping and high-strength properties seem to contradict each other, and even mineralized hydrogels, which already have excellent strength and bone induction properties, are not ideal candidates, since they lack the plasticity needed for complex craniofacial surface use during the essential mechanism of the process of the cleavage of inorganic ions, nucleation, and growth. Here, we report a novel mineralized hydrogel based on dispersing mineral ions prior to use and then inducing inorganic formation by decreasing the temperature, which endows the hydrogels with the characteristics of precise customization at an appropriate degree of mineralization and simultaneously achieves suitable mechanical properties and sufficient calcium supply for bone regeneration. Additionally, the calcium ion content in the water of the matrix will change with the temperature, and, thus, the conductivity of the mineralized hydrogels will change accordingly. This implements the ability to warn of inflammation in a timely fashion in the form of a temperature sensor. Therefore, this temperature-responsive hydrogel effectively achieves the aim of versatile material design.

In situ mechanical reinforcement of polymer hydrogels via metal-coordinated crosslink mineralization

Biological organic-inorganic materials remain a popular source of inspiration for bioinspired materials design and engineering. Inspired by the self-assembling metal-reinforced mussel holdfast threads, we tested if metal-coordinate polymer networks can be utilized as simple composite scaffolds for direct in situ crosslink mineralization. Starting with aqueous solutions of polymers end-functionalized with metal-coordinating ligands of catechol or histidine, here we show that inter-molecular metal-ion coordination complexes can serve as mineral nucleation sites, whereby significant mechanical reinforcement is achieved upon nanoscale particle growth directly at the metal-coordinate network crosslink sites.

Biological organic-inorganic materials, such as self-assembling metal-reinforced mussel holdfast threads, remain a popular source of inspiration for materials design and engineering. Here the authors show that metal-coordinate polymer networks can be utilized as simple composite scaffolds for direct in situ crosslink mineralization.

The preparation, structure and luminescent properties of Mg–CaCO3:Eu3+ phosphors

Morphology and luminescence properties of Mg–CaCO₃:Eu³⁺ phosphors are found to change with the initial magnesium ion concentration.