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In bone tissue engineering, suitable mechanical properties and excellent biological performance of biological substitutes are required. β-tricalcium phosphate has superior biocompatibility compared to other calcium phosphate ceramics, but poor osteoinductive properties. Among all calcium phosphates, octacalcium phosphate exhibits excellent osteoconductivity and osteoinductivity. Therefore, it is expected to have novel biological properties combining these two materials together. The FTIR and XRD results confirm abstract that pure β-tricalcium phosphate and octacalcium phosphate mixed powder is synthesized through co-precipitation method. Bulk composites of β-tricalcium phosphate and octacalcium phosphate are produced using molding and cold isostatic pressing technique. The composites exhibit suitable compressive strength and porosities of more than 33%, which meet the requirement for bone substitute materials well. In addition, a layer of hydroxyapatite is deposited on the surface of the material in simulated body fluids. This work provides a new artificial bone substitute material for the bone tissue engineering. [ABSTRACT FROM AUTHOR]

The present study investigated the dose-dependent effect of inositol on the thermally induced crystallization and phase evolution of amorphous calcium phosphate. It has been demonstrated that the crystallization of amorphous calcium phosphate was postponed by the introduction of inositol. The initial crystallize phase under 600 °C and thermodynamic equilibrium between α/β-tricalcium phosphate (TCP) under higher temperatures were altered in a content-dependent manner. Smaller amounts of inositol could promote the formation of α-TCP-like hydroxyapatite and expand the annealing temperature range to obtain pure α-TCP, while larger amounts would exhibit the opposite effect and promote the formation of β-TCP. This discovery could be used to guide the production of α/β-TCP. [ABSTRACT FROM AUTHOR]

Biphasic calcium phosphate (BCP) is an important research field based on calcium phosphate biomaterials. In this paper, a new synthesis method of CDHA/α-TCP BCP was studied. By controlling the addition amount of citric acid, the relative contents of CDHA and α-TCP in the BCP were controlled. BCP bone cement was prepared with different proportions of BCP as raw materials. The BCP bone cement was characterized by XRD and SEM, and evaluated by measuring setting time, compressive strength, SBF immersion, and colorimetric CCK-8 assay. The results showed that the increase of CDHA content can lead to the reduction of the setting time of bone cement and delay the degradation rate of BCP bone cement. [ABSTRACT FROM AUTHOR]

Strontium has been widely used in bone repair materials due to its roles in promoting osteoclast apoptosis and enhancing osteoblast proliferation. In this work, synthesis and the effects of Sr2+ doping α-tricalcium phosphate at low-temperature was studied. The setting time and the mechanical properties of α-tricalcium phosphate were controlled by varying the content of Sr2+. The synthesized compounds were evaluated by XRD, SEM, XPS, setting time, compressive strength, SBF immersion, and colorimetric CCK-8 assay. The results showed that Sr2+ can improve the compressive strength and cell activity of calcium phosphate bone cement. [ABSTRACT FROM AUTHOR]

Strontium has been widely used in bone repair materials due to its roles in promoting osteoclast apoptosis and enhancing osteoblast proliferation. In this work, synthesis and the effects of Sr2+ doping α-tricalcium phosphate at low-temperature was studied. The setting time and the mechanical properties of α-tricalcium phosphate were controlled by varying the content of Sr2+. The synthesized compounds were evaluated by XRD, SEM, XPS, setting time, compressive strength, SBF immersion, and colorimetric CCK-8 assay. The results showed that Sr2+ can improve the compressive strength and cell activity of calcium phosphate bone cement. [ABSTRACT FROM AUTHOR]

Magnetic nanoparticles with a general formula of MFe 2 O 4 (M = Fe, Mn, Zn, Mg, Co, Ca) have attracted much attention owing to their biocompatibility, chemical stability under physiological conditions and superparamagnetic properties. In this paper, with the chloride as the primary materials and NaOH as precipitating agent, Mg–Zn ferrite nanoparticles were prepared and characterised by X-ray diffraction (XRD), scanning electron microscope (SEM), vibrating sample magnetometer (VSM) and the heat analysis system. The X-ray diffraction analysis revealed that the structure of these nanoparticles was spinel, and the Zn concentration and calcination temperature had a significant influence on the degree of crystallinity. The heating capacity first increased and then decreased with increasing of zinc content, while the calcination temperature increased the heating capacity generally. The AC magnetic-filed-induced heating characteristics of Mg 0.4 Zn 0.6 Fe 2 O 4 indicated that the magnetic nanoparticles increased from the room temperature up to 43 °C in a time less than 3 min, and remained stable in 43–50 °C for 57 min. Image 1014 • Mg 1-x Zn x Fe 2 O 4 ferrites were fabricated by co-precipitation method. • The increase of zinc doping will increase the induction heating properties first and then decreases. • Rising calcination temperature increases the induction heating properties as a whole. • It is a potential candidate for magnetic hyperthermia treatment with controllable heating rate and range. [ABSTRACT FROM AUTHOR]

The up-converted persistent luminescence properties of the Zn 3 Ga 2 SnO 8 : 1%Cr3+, 5%Yb3+, 0.5%Er3+ nano material are shown to be much improved when it is fabricated by unsophisticated hydrothermal method. This kind of nano phosphor with special structure shows up-converted long persistent luminescence over 20 min and long persistent luminescence over 60 min in the near-infrared region, and permits bright, clear and reliable imaging. Moreover, the up-convered persistent luminescence, persistent luminescence, up conversion luminescence and photoluminescence properties are provided on this nano preparation, simultaneously. In addition, This new nano Zn 3 Ga 2 SnO 8 :Cr3+, Yb3+, Er3+ phosphor will allow to have important implications for multifarious and systematic investigations,such as in cells, tissues and other complex systems. [ABSTRACT FROM AUTHOR]

In this work, fluorescent α-tricalcium phosphate (α-TCP: Yb3+,Er3+) was successfully prepared by the thermal transformation of amorphous calcium phosphate (ACP) precursor. β-cyclodextrin (β-CD) was used for preparation of ACP precursor and played an important role in designing its special structure. Due to the new low temperature preparation of α-tricalcium phosphate, the obtained microsphere has a uniform distribution with rational strength (15.0 Mpa). Futhermore, the two ions (Yb3+,Er3+) were doped into α-tricalcium phosphate (α-TCP), the obtained phosphor can emit exhibit bright green luminescence under the excitation of a 980 nm laser diode. The α-TCP: Yb3+,Er3+ may have great potential in the fields of in vivo bio-imaging and a drug delivery system. [ABSTRACT FROM AUTHOR]