Cong Feng

Bio: Cong Feng is an academic researcher from Sichuan University. The author has contributed to research in topics: Simulated body fluid & Ceramic. The author has an hindex of 1, co-authored 5 publications receiving 1 citations.

Effect of Hydrothermal Media on the in-situ Whisker Growth on Biphasic Calcium Phosphate Ceramics

Abstract: Background There is still a big challenge to achieve a balance between mechanical characteristics and biological properties in biphasic calcium phosphate (BCP) ceramics. Purpose The present study focused on the in-situ whisker growth on BCP ceramics via different hydrothermal treatments and investigated the influences of these whiskers on the mechanical property and biological performance of the ceramics. Methods Five kinds of BCP ceramics with in-situ whisker growth, ie, BCP-C, BCP-HNO3, BCP-Citric, BCP-NaOH, BCP-CaCl2 and BCP-Na3PO4 were fabricated by different hydrothermal treatments. The phase compositions, morphologies, crystal structures and mechanical strengths of the obtained BCP ceramics were firstly characterized. Then, the in vitro cell adhesion, proliferation and alkaline phosphatase (ALP) activity of bone marrow stromal cells (BMSCs) on the BCP ceramics were evaluated. Lastly, the effects of in-situ whisker growth on the bone-like apatite formation abilities of BCP ceramics were also investigated by immersing them in simulated body fluid (SBF). Results The results demonstrated that the hydrothermal conditions, especially the hydrothermal media, were crucial to determine the phase composition and morphology of the in-situ whisker. Especially among the five media used (HNO3, Citric, NaOH, CaCl2 and Na3PO4), the Na3PO4 treatment resulted in the shortest whisker with a unique hollow structure, and kept the original biphasic composition. All five kinds of whiskers increased the mechanical strength of BCP ceramics to some extent, and showed the good ability of bone-like apatite formation. The in vitro cell study demonstrated that the in-situ whisker growth had no adverse but even positive effect on the adhesion, proliferation and ALP activity of BMSCs. Conclusion Due to the growth of in-situ whiskers, the mechanical property and biological performance of the obtained BCP ceramics could increase simultaneously. Therefore, in-situ whiskers growth offers a promising strategy for the expanded application of BCP ceramics to meet the requirements of regenerative medicine.

Osteoinductive calcium phosphate ceramic with hollow tube structure and preparation method of osteoinductive calcium phosphate ceramic

Abstract: The invention belongs to the technical field of biomedical materials, and discloses an osteoinductive calcium phosphate ceramic with a hollow tube structure and a preparation method of the osteoinductive calcium phosphate ceramic. The problem of contradiction between osteoinductive optimization and mechanical strength improvement of calcium phosphate ceramic in the prior art is solved. The preparation method comprises the following steps: placing porous calcium phosphate ceramic in a neutral or alkaline phosphorus-containing solution, and carrying out hydrothermal reaction and heat treatment to obtain the osteoinductive calcium phosphate ceramic with the hollow tube structure on the surface. The osteoinductive calcium phosphate ceramic with the hollow tube structure has the advantages of scientific design, simple method and simplicity and convenience in operation, and the osteoinductive calcium phosphate ceramic with the hollow tube structure on the surface is obtained through hydrothermal treatment and heat treatment. The calcium phosphate ceramic with the hollow tube structure not only has excellent osteoinductive capacity, but also has better mechanical strength, and meets the requirements of clinical partial bearing bone defect repair and regeneration.

Calcium Phosphate-Based Biomaterials for Bone Repair

Abstract: Traumatic, tumoral, and infectious bone defects are common in clinics, and create a big burden on patient’s families and society. Calcium phosphate (CaP)-based biomaterials have superior properties and have been widely used for bone defect repair, due to their similarities to the inorganic components of human bones. The biological performance of CaPs, as a determining factor for their applications, are dependent on their physicochemical properties. Hydroxyapatite (HAP) as the most thermally stable crystalline phase of CaP is mostly used in the form of ceramics or composites scaffolds with polymers. Nanostructured CaPs with large surface areas are suitable for drug/gene delivery systems. Additionally, CaP scaffolds with hierarchical nano-/microstructures have demonstrated excellent ability in promoting bone regeneration. This review focuses on the relationships and interactions between the physicochemical/biological properties of CaP biomaterials and their species, sizes, and morphologies in bone regeneration, including synthesis strategies, structure control, biological behavior, and the mechanisms of CaP in promoting osteogenesis. This review will be helpful for scientists and engineers to further understand CaP-based biomaterials (CaPs), and be useful in developing new high-performance biomaterials for bone repair.

Bone‐on‐a‐Chip: A Microscale 3D Biomimetic Model to Study Bone Regeneration

Abstract: Organ-on-chip models, developed using microengineering and microfluidic technologies, aim to recreate physiological-like microenvironments of organs or tissues as a tool to study (patho)physiological processes in vitro. On-chip models of bone are relevant for the study of bone physiology, diseases and regenerative processes. While a few bone-on-a-chip models exist, recapitulating the cellular components of bone, these models do not incorporate the chemical and structural characteristics of bone tissue. Herein, the development of a bone-on-a-chip platform is reported that comprises a 3D structural model of bone. To build the platform, first, a 3D model of bone is produced in a polymer using two-photon polymerization (2PP) from a 3D nano-computed tomography scan of trabecular bone. This 3D model is then coated with a layer of bone mineral-like calcium phosphate. Finally, the 3D bone model is integrated inside a microfluidic device suitable for cell culture. Human mesenchymal stromal cells, cultured inside the platform for up to 21 days, show high viability and extensive production of extracellular matrix, rich in collagen. This biomimetic bone-on-a-chip platform can contribute to a better understanding of the processes related to bone formation and remodeling, which in turn can be used for the development of bone regeneration strategies.