Synergistic intrafibrillar/extrafibrillar mineralization of collagen scaffolds based on a biomimetic strategy to promote the regeneration of bone defects

Abstract

The mineralization of collagen scaffolds can improve their mechanical properties and biocompatibility, thereby providing an appropriate microenvironment for bone regeneration. The primary purpose of the present study is to fabricate a synergistically intra- and extrafibrillar mineralized collagen scaffold, which has many advantages in terms of biocompatibility, biomechanical properties, and further osteogenic potential. In this study, mineralized collagen scaffolds were fabricated using a traditional mineralization method (ie, immersed in simulated body fluid) as a control group and using a biomimetic method based on the polymer-induced liquid precursor process as an experimental group. In the polymer-induced liquid precursor process, a negatively charged polymer, carboxymethyl chitosan (CMC), was used to stabilize amorphous calcium phosphate (ACP) to form nanocomplexes of CMC/ACP. Collagen scaffolds mineralized based on the polymer-induced liquid precursor process were in gel form such that nanocomplexes of CMC/ACP can easily be drawn into the interstices of the collagen fibrils. Scanning electron microscopy and transmission electron microscopy were used to examine the porous micromorphology and synergistic mineralization pattern of the collagen scaffolds. Compared with simulated body fluid, nanocomplexes of CMC/ACP significantly increased the modulus of the collagen scaffolds. The results of in vitro experiments showed that the cell count and differentiated degrees in the experimental group were higher than those in the control group. Histological staining and micro-computed tomography showed that the amount of new bone regenerated in the experimental group was larger than that in the control group. The biomimetic mineralization will assist us in fabricating a novel collagen scaffold for clinical applications.

The Efficacy of Graphene Foams for Culturing Mesenchymal Stem Cells and Their Differentiation into Dopaminergic Neurons

“…The X-ray diffraction (XRD) peaks of collagen-coated GF confirmed that they existed in separate planes. In addition, they did not interact with each other which is supported by their distinct peak positions without any considerable change that is supported by the above references [ 33 , 35 , 36 ].…”

“…The two diffraction peaks at 2 θ = 26.5° and 2 θ = 55° correspond to the (002) and (004) planes of graphene, respectively, where the intensity of the peak at 2 θ = 26.5° got reduced for the collagen coating [ 33 , 35 ]. The diffraction peaks of collagen appeared to correspond to the crystallographic planes (211) and (222) at about 2 θ = 32° and 2 θ = 45.3° indicating a traditional mineralized collagen [ 36 ]. The X-ray diffraction (XRD) peaks of collagen-coated GF confirmed that they existed in separate planes.…”

Stem Cell-Friendly Scaffold Biomaterials: Applications for Bone Tissue Engineering and Regenerative Medicine

“…Collagen has also been utilized in guided bone regeneration procedures due to their biodegradability, osteoconduction, and osteoinduction (Ferreira et al, 2012 ). Collagen scaffolds provide an ideal environment for bone formation (Wang et al, 2016 ). They also serve as the best carrier for targeted delivery of small molecules such as antagonists of miR-16, which increases the relative levels of Runx2 and osteocalcin, thereby promoting mineral calcium deposition (Mencía Castaño et al, 2019 ).…”

Effects of proanthocyanidin, a crosslinking agent, on physical and biological properties of collagen hydrogel scaffold

“…Among these, scaffolds play a crucial role in tissue engineering by mimicking the function of the extracellular matrix (ECM), and by offering a three-dimensional spaciotemporal microenvironment for cell attachment, migration, proliferation, differentiation, and metabolism1314 A suitable scaffold also has other characteristics including a highly porous interconnected network with proper surface properties, biocompatibility, and biodegradability harmonious with the rate of cell/tissue growth and maturation 1115. Collagen, a significant constituent of the natural ECM, has been regarded as the ideal material for soft tissue engineering constructs due to its excellent biocompatibility and biodegradability 161718. However, collagen-based scaffolds have a crucial limitation on the use of artificial substitutes because of its high degradation rate and poor mechanical properties 161718.…”

“…Collagen, a significant constituent of the natural ECM, has been regarded as the ideal material for soft tissue engineering constructs due to its excellent biocompatibility and biodegradability 161718. However, collagen-based scaffolds have a crucial limitation on the use of artificial substitutes because of its high degradation rate and poor mechanical properties 161718. Therefore, the crosslinking of collagen is an effective strategy to modify the drawbacks and provide strength, reinforcement, and stabilization to the fibrils enough to be used as biomaterials 1719.…”