Magnesium-Rich Calcium Phosphate Derived from Tilapia Bone Has Superior Osteogenic Potential

We extracted magnesium-rich calcium phosphate bioceramics from tilapia bone using a gradient thermal treatment approach and investigated their chemical and physicochemical properties. X-ray diffraction showed that tilapia fish bone-derived hydroxyapatite (FHA) was generated through the first stage of thermal processing at 600-800 °C. Using FHA as a precursor, fish bone biphasic calcium phosphate (FBCP) was produced after the second stage of thermal processing at 900-1200 °C. The beta-tricalcium phosphate content in the FBCP increased with an increasing calcination temperature. The fact that the lattice spacing of the FHA and FBCP was smaller than that of commercial hydroxyapatite (CHA) suggests that Mg-substituted calcium phosphate was produced via the gradient thermal treatment. Both the FHA and FBCP contained considerable quantities of magnesium, with the FHA having a higher concentration. In addition, the FHA and FBCP, particularly the FBCP, degraded faster than the CHA. After one day of degradation, both the FHA and FBCP released Mg²⁺, with cumulative amounts of 4.38 mg/L and 0.58 mg/L, respectively. Furthermore, the FHA and FBCP demonstrated superior bone-like apatite formation; they are non-toxic and exhibit better osteoconductive activity than the CHA. In light of our findings, bioceramics originating from tilapia bone appear to be promising in biomedical applications such as fabricating tissue engineering scaffolds.

Enhanced bone tissue regeneration via bioactive electrospun fibrous composite coated titanium orthopedic implant

One of the very reliable, attractive, and cheapest techniques for synthesizing nanofibers for biomedical applications is electrospinning. Here, we have created a novel nanofibrous composite coated Ti plate to mimic an Extra Cellular Matrix (ECM) of native bone in order to enhance the bone tissue regeneration. An electrospun fibrous composite was obtained by the combination of minerals (Zn, Mg, Si) substituted hydroxyapatite (MHAP)/Polyethylene Glycol (PEG)/Cissus quadrangularis (CQ) extract. Fibrous composite's functionality, phase characteristics, and morphology were evaluated by FT-IR, XRD, and SEM techniques, respectively. The average fiber diameter of MHAP/PVA had decreased from ~274 to ~255 nm after incorporating PEG polymer. That further increased from ~255 to ~275 nm after adding CQ extract. Besides the bioactivity in SBF solution, the degradable nature was confirmed by immersing the fibrous composite in Tris-HCL solution. The degradable studies evaluate that the composite was degraded depending on time, and it degrades about 9.42% after 7 days of immersion. Osteoblasts like MG-63 cells differentiation, proliferation, and calcium deposition were also determined. These results show that this new fibrous composite exhibits advanced osteoblasts properties. Thus, we concluded that this new fibrous scaffold coated Ti implant could act as a better implant to mimic ECM of bone structure and to improve osteogenesis during bone regeneration.

Fabrication of substituted hydroxyapatite-starch-clay bio-composite coated titanium implant for new bone formation

The clay/polymeric matrices have much attention from researchers in bio-medical applications due to their numerous uses. This study introduces new orthopedic titanium (Ti) implant with increasing bio-activity by treating the surface of the Ti implant with bio-compatible composite coating. Wollastonite (WST) clay combined minerals (Mg²⁺and Gd³⁺) substituted hydroxyapatite (HAP)/Starch composite was prepared using in-situ co-precipitation method. It was successfully coated on the orthopedic grade Ti plate by the Electrophoretic Deposition (EPD) method. The functionality, phase, morphology, and bio-activity analysis of the composite were evaluated by FT-IR, XRD, HR-TEM, and SEM analysis, respectively. The mechanical property, i.e., Vickers microhardness value of the MHAP/Starch/WST composite coated Ti plate, showed 242 ± 1.92 Hv. The in-vitro MG-63 osteoblast cells viability, differentiation, and Ca mineralization of MHAP/Starch/WST composite suggests that this new implant will be used for bone regeneration application after careful evaluation of in-vivo and clinical studies.

Novel composite scaffolds based on alginate and Mg-doped calcium phosphate fillers: Enhanced hydroxyapatite formation under biomimetic conditions

In the present study, we synthesized hydroxyapatite (HAP) powders followed by the production of alginate based macroporous scaffolds with the aim to imitate the natural bone structure. HAP powders were synthesized by using a hydrothermal method, and after calcination, dominant phases in the powders, undoped and doped with Mg²⁺ were HAP and β-tricalcium phosphate, respectively. Upon mixing with Na-alginate, followed by gelation and freeze-dying, highly macroporous composite scaffolds were obtained with open and connected pores and uniformly dispersed mineral phase as determined by scanning electron microscopy. Mechanical properties of the scaffolds were influenced by the composition of calcium phosphate fillers being improved as Ca²⁺ concentration increased while Mg²⁺ concentration decreased. HAP formation within all scaffolds was investigated in simulated body fluid (SBF) during 28 days under static conditions while the best candidate (Mg substituted HAP filler, precursor solution with [Ca + Mg]/P molar ratio of 1.52) was investigated under more physiological conditions in a biomimetic perfusion bioreactor. The continuous SBF flow (superficial velocity of 400 μm/s) induced the formation of abundant HAP crystals throughout the scaffolds leading to improved mechanical properties to some extent as compared to the initial scaffolds. These findings indicated potentials of novel biomimetic scaffolds for use in bone tissue engineering.

Self-assembly pore-forming mechanism of foam boundary templates and the preparation of porous strontium hydroxyapatite microspheres by homogeneous precipitation

The preparation of porous SrHAp microspheres, and the self-assembly pore-forming process and mechanism of a foam boundary template were systematically presented.

S. N. SN, Sagadevan S, Hoque ME, Kulandaivelu R. Advanced lithium substituted hydroxyapatite nanoparticles for antimicrobial and hemolytic studies

In this study, pure hydroxyapatite (HAP) and lithium substituted hydroxyapatite (Li-HAP) nanoparticles were synthesized by a sonochemical synthesis process and investigated for their antimicrobial and hemolytic activities.

Effect of magnesium particle fraction on osteoinduction of hydroxyapatite sphere-based scaffolds

HAs-30Mg (incorporation of 30% Mg into HA sphere-based scaffolds) induced the optimum new bone formation.

Physico-mechanical properties of Mg and Ag doped hydroxyapatite/chitosan biocomposites

Co-Substituted hydroxyapatite Mg–Ag-HAP/chitosan biocomposites were synthesized successfully using a simple chemical method, and the compressive strength progressed up to 15.2 MPa atx= 0.8.