A biomimetic mineralized collagen hydrogel containing uniformly distributed and highly abundant dopamine‐modified hydroxyapatite particles for bone tissue engineering

Abstract

In this study, hydroxyapatite (HAp)/mineralized collagen hydrogel composites were prepared by incorporating different amounts of dopamine‐modified HAp particles during the process of collagen self‐assembly and simultaneous mineralization. Zeta potential results showed that the surface charge of modified HAp particles was altered, and scanning electron microscopy patterns indicated that HAp particles were uniformly distributed in the hydrogels. The occurrence of collagen biomineralization was indirectly reflected by the results of Ca and P content in the hydrogel supernatant, and the results of ash content indicated that the mineral content of the hydrogels could be up to 60% or more, which was close to the inorganic content in natural bone. The results of CCK‐8 and ALP activity assays showed that mineralized collagen hydrogels were favorable for cell proliferation and differentiation, and the hydrogels containing dopamine‐modified HAp particles obtained a higher expression of osteogenic differentiation related transcription factor. The results showed that the excellent adhesion properties of dopamine contributed to enhance the bone repair potential of the composites, suggesting that mineralized collagen hydrogel composites containing dopamine‐modified HAp particles, which could mimic the structure and composition of bone, have a promising potential as bone tissue engineering scaffolds.