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This article reviews the strategies of maximizing CO2 photoreduction rates in distinguished ZnS-based photocatalytic systems by continuously optimizing the reaction medium and photocatalysts.

A rod-like melem with high fluorescence quantum yield of 71.3 % was prepared in this work to enhance the chemiluminescence (CL) intensity of Na

In this work, an Au modified Bi2O3-TiO2 (Au/Bi2O3-TiO2) hybrid is developed as a simple and effective photocatalyst for the production of H2O2. The modification of Bi2O3 improves the charge separation of photocatalyst and significantly enhances the photocatalytic activity of Au/TiO2 for H2O2 production. In-situ electron spin resonance studies shows stepwise single-electron oxygen reduction reaction (ORR) on the Au/Bi2O3-TiO2 photocatalyst for the production of H2O2. This work demonstrates the importance of heterojunction structure photocatalyst for improved performance of TiO2 in order to produce concentrated H2O2.

In this work, Au-modified F-TiO2 is developed as a simple and efficient photocatalyst for H2O2 production under ultraviolet light. The Au/F-TiO2 photocatalyst avoids the necessity of adding fluoride into the reaction medium for enhancing H2O2 synthesis, as in a pure TiO2 reaction system. The F− modification inhibits the H2O2 decomposition through the formation of the ≡Ti–F complex. Au is an active cocatalyst for photocatalytic H2O2 production. We compared the activity of TiO2 with F− modification and without F− modification in the presence of Au, and found that the H2O2 production rate over Au/F-TiO2 reaches four times that of Au/TiO2. In situ electron spin resonance studies have shown that H2O2 is produced by stepwise single-electron oxygen reduction on the Au/F-TiO2 photocatalyst.

In this work, doxorubicin (DOX) was intercalated into layered nanohydroxyapatite (LHAp). The drug loaded LHAp (DOX@LHAp) was then mixed with poly(lactic-co-glycolic acid) (PLGA) and electrospun to yield DOX@LHAp/PLGA composite scaffolds. As control, needle-like nanohydroxyapatite (nHAp) was also used to make an DOX@nHAp/PLGA composite scaffold and bare DOX was used to fabricate DOX/PLGA scaffold. The morphology, release behavior of DOX, and capability to inhibit cancer cells were assessed. The addition of DOX-loaded nHAp to PLGA causes a slight decrease in the average fiber diameter of DOX@LHAp/PLGA as compared to PLGA. The in vitro drug release tests reveal a much faster release of DOX from DOX/PLGA than DOX@LHAp/PLGA. Moreover, DOX@LHAp/PLGA displays a more sustainable release over DOX@nHAp/PLGA due to the storage of DOX in the gallery of LHAp, which is further proved by their cancer cell inhibition results. We believe that the DOX@LHAp/PLGA scaffold has potential as an implantable drug delivery system.

An oxidized, porous graphitic carbon nitride nanosheets (CNNs) was successfully obtained via a bottom-up approach. The inner filter effect (IFE) of Fe (III) tetrakis (1-methyl-4-pyridyl) porphyrin pentachlorideporphyrin pentachloride (FeTMPyP) on the CNNs results in fluorescence quenching of the CNNs due to the overlap of FeTMPyP absorbance band and CNNs emission band. It is interesting that the quenched fluorescence could be "turned on" in response to the participation of H2 O2 , which caused by decomposition of FeMPyP. In this study, for the first time, a porous fluorescence probe based on CNNs and FeTMPyP was designed and an excellent H2 O2 detection performance with a large detection range of 0.1 ~ 100 μM and a detection limit of 0.07 μM was achieved. Furthermore, the proposed method was successfully used for H2 O2 detection in RAW 264.7 cells.

In this work, graphitic carbon nitride (g-C3N4) supporting finely dispersed Au nanoparticles is developed as a simple and efficient photocatalyst for H2O2 production under visible light irradiation. Au nanoparticle cocatalyst remarkably enhances photocatalytic activity of C3N4 for H2O2 production. Due to the inert nature to catalyze the decomposition of H2O2, Au/C3N4 also exhibits stable H2O2 evolution rate. It is of great interest that the maximal H2O2 production activity is reached at the loading amount of Au as low as 0.01%, revealing the great catalytic efficacy of highly dispersed Au cocatalyst during the photocatalytic H2O2 synthesis and the possibility to produce concentrated H2O2 using C3N4 with extremely low Au loading amount. The in situ electron spin resonance studies reveal that the H2O2 is produced through direct 2e− oxygen reduction over Au/C3N4 photocatalyst.

An ideal photocatalyst that can promisingly convert CO2 should have suitable band gap and fully consider the activation of reaction. However, well-designed photocatalytic materials with these aspects are very limited. This study reports a highly efficient CO2 reduction photocatalyst based on ZnS nanocrystals which can be rapidly synthesized at room temperature and operated under solar light irradiation at all-inorganic reaction system. Two functional elements, Cu and Cd, are respectively used as dopant and cocatalyst of ZnS nanocrystal for selective CO2 reduction. Cu+ doping expands the photoabsorption of ZnS into visible light region and the simultaneous Cd2+ surface modification significantly improves the activity of CO2 reduction with 99% formic acid selectivity. A combination of charge density distribution and electronic state studies reveal that the Cd s orbital displays obviously higher density of states near band-edge with a relatively lower lying band center than that of Zn s orbital. This will greatly favor the charge transfer from conduction band of ZnS to the surface state created by Cd2+ for catalyzing CO2 reduction.

OBJECTIVE: To investigate the effect of zoledronate (ZOL) on osteoclast differentiation and bone resorption under high glucose, and the regulation mechanism of p38 mitogen activated kinase (p38 MAPK) signaling pathway in this process. METHODS: RAW264.7 cells were divided into four groups: low group, high group, low+ZOL group and high+ZOL group after induced into osteoclasts. Cell proliferation activity was determined by MTT assay. The migration of RAW264.7 cells were examined Optical microscopy. Immunofluorescence microscopy was used to observe the cytoskeleton and sealing zones of osteoclasts. After adding group 5: high + ZOL + SB203580 group, trap staining was used to identify the number of positive osteoclasts in each group. The number and area of resorption lacunae were observed by SEM. The mRNA and protein expression of osteoclast related factors were detected by real-time PCR and Western blotting. RESULTS: The cells in the 5 groups showed similar proliferative activity. High glucose promoted the migration of RAW264.7 cells (P < 0.05), inhibited the clarity of cytoskeleton and the formation of sealing zones in the osteoclasts. Exposure to high glucose significantly lowered the expressions of p38 MAPK, p-p38 MAPK, NFATc1, CTSK and TRAP, and inhibited osteoclast differentiation and bone absorption (P < 0.05). Treatment with ZOL obviously suppressed the migration ability of RAW264.7 cells, further reduced the clarity of the cytoskeleton, inhibited the formation of sealing zones of the osteoclasts, lowered the expressions of p38 MAPK, p-p38 MAPK, NFATc1, CTSK, and TRAP (P < 0.05), and inhibited osteoclast differentiation and bone absorption. Treatment with SB203580 obviously inhibited osteoclast differentiation and bone resorption and the expressions of P38 MAPK, p-p38 MAPK, NFATc1, CTSK and TRAP (P < 0.05). CONCLUSIONS: High glucose inhibits osteoclast differentiation and bone resorption. ZOL inhibits osteoclast differentiation and bone resorption in high-glucose conditions by regulating p38 MAPK pathway, which can be a new pathway for ZOL to regulate diabetic osteoporosis.

Rational structure, mechanical robustness, high conductivity, and favorable flexibility are important requirements for superior electrodes, which should not only possess high capacitance but also have freestanding structure without collector to improve the overall performance of supercapacitors. Herein, we demonstrate the fabrication of three-dimensional (3D) porous graphene-containing nanocomposites with highly dispersed graphene (GE) nanosheets in a 3D matrix of bacterial cellulose (BC) by a novel layer-by-layer in situ culture (LBLC) method. The BC/GE nanocomposites are then deposited with polyaniline (PANI), leading to the formation of BC/GE/PANI nanocomposites. Mechanical tests demonstrate excellent robustness and flexibility of the as-prepared BC/GE/PANI nanocomposites, which are used as electrodes directly without any nickel foam or stainless steel wire. The BC/GE/PANI electrode with an optimal GE content has a specific capacitance of 645 F g−1 at a current density of 1 A g−1, which is 2.5 times higher than that of BC/PANI and superior to most previously reported PANI-based electrodes. In addition, the symmetric supercapacitor assembled with BC/GE/PANI demonstrates a high energy density of 14.2 Wh kg−1 at a power density of 200 W kg−1. The excellent electrochemical performance of this BC/GE/PANI electrode is due to its unique 3D porous structure with the uniform distribution of GE nanosheets in the BC matrix and even PANI on BC nanofibers and GE nanosheets, which makes it very promising for diverse flexible energy storage devices. The methodology presented in this work can be extended to the preparation of other BC-based nanocomposite electrodes.

The design and synthesis of multifunctional hydroxyapatite (HAp) nanoparticles are important in expanding their clinical applications. Herein we report a novel selenium (Se) and gadolinium (Gd) dual-doped lamellar hydroxyapatite (L-HAp-Se-Gd) produced by facile one-step template-assisted synthesis. The results show that the as-prepared L-HAp-Se-Gd nanoparticles exhibit obvious changes in morphology, dimensions, and crystallinity as compared to bare L-HAp. XRD results reveal that high dopant levels of Se and Gd reduce the degree of ordering of HAp lamellae. It is found that the L-HAp-Se-Gd nanoparticles display Gd content-dependent blue fluorescence under ultraviolet (UV) irradiation and magnetic properties. Cell tests with mouse embryo osteoblast cells (MC3T3-E1) reveal their improved biocompatibility over bare L-HAp due to Se incorporation. These results indicate that L-HAp-Se-Gd nanoparticles have potential in numerous applications such as multifunctional gene delivery and bioimaging.

The BaZr0.2Ti0.8O3 ceramics with perovskite structure were prepared by solid state reaction method with addition of x La2O3 and x La2O3 + 0.2 wt% Sm2O3 (x = 0.0, 0.1 and 0.4 wt%). Microstructure and dielectric behaviour of the obtained ceramics were respectively investigated. The compositions of these ceramics demonstrated a single-phase cubic symmetry in a room-temperature X-ray diffraction study. The dielectric constant peak of those samples with addition of x La2O3 and x La2O3 + 0.2 wt% Sm2O3 greatly reduced along with increasing x. Simultaneously, a drastic increase of the values of γ was also observed when x rose, exhibiting a diffuse phase transition. T m increased along with increasing La content for x La2O3 doped BZT20 ceramics, but decreased along with increasing La content for x La2O3 + 0.2 wt% Sm2O3 doped BZT20 ceramics. Owing to the doping of Sm3+, the x La2O3 + 0.2 wt% Sm2O3 doped BZT20 ceramics have maintained very low and stable dissipation factors under an increasing environment temperature, making them superior candidates for applications.

Nano-hydroxyapatite samples with different morphologies were successfully prepared by chemical precipitation method using polyethylene glycol (PEG) as a template. The phase composition, micro-morphology and surface functional groups of the nano-hydroxyapatite samples were analyzed by X-ray diffraction (XRD), scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR) and transmission electron microscopy (TEM), respectively. The results reveal that the mirco-morphology of hydroxyapatite can be effectively controlled by adjusting pH values in the preparation. Moreover, the growth mechanism of HAp with different morphologies was also discussed.

In this study, Sr1.94MgSi2O7: 0.02Eu2+, 0.04Dy3+ and Sr1.928MgSi2O7: 0.02Eu2+, 0.04Dy3+, 0.012Nd3+ long afterglow luminescent materials were successfully synthesized via the sol–gel method under reducing atmosphere at 1100 °C for 3 h. No phase structure effect of Sr2MgSi2O7, or significant lattice distortion occurred while a small amount of rare earth ions were doped. Moreover, co-doping Sr2MgSi2O7: Eu2+, Dy3+ with Nd3+ has virtually no effect on the morphology of Sr2MgSi2O7: Eu2+, Dy3+. Co-doping Sr2MgSi2O7: Eu2+, Dy3+ with Nd3+ has also no evident effect on the position of the fluorescence emission peak. However, the applied concentration of Nd3+ co-doping created deeper traps and enhanced the afterglow properties of Sr2MgSi2O7: Eu2+, Dy3+.

Photocatalysis provides an attractive strategy for synthesizing H2O2 at ambient condition. However, the photocatalytic synthesis of H2O2 is still limited due to the inefficiency of photocatalysts and decomposition of H2O2 during formation. Here, we report SnO2-TiO2 heterojunction photocatalysts for synthesizing H2O2 directly in aqueous solution. The SnO2 passivation suppresses the complexation and decomposition of H2O2 on TiO2. In addition, loading of Au cocatalyst on SnO2-TiO2 heterojunction further improves the production of H2O2. The in situ electron spin resonance study revealed that the formation of H2O2 is a stepwise single electron oxygen reduction reaction (ORR) for Au and SnO2 modified TiO2 photocatalysts. We demonstrate that it is feasible to enhance H2O2 formation and suppress H2O2 decomposition by surface passivation of the H2O2-decomposition-sensitive photocatalysts.

Magnetic carbon nitride composites were synthesized via a solvothermal reaction and developed as an effective adsorbent for magnetic solid-phase extraction of trace hydroxylated polycyclic aromatic hydrocarbons (OH-PAHs) from urine samples prior to their determination by HPLC. The sorbent was characterized by Fourier transform infrared spectrometry, X-ray diffractometry, scanning electron microscopy, vibrating sample magnetometry and solvent stability experiments. The adsorption of hydroxy-PAHs is better by a factor or 20 to 49 compared to bare Fe3O4 and comparable that of a commercial C18 sorbent. The adsorbent amount, adsorption time and eluting solvent and volume were optimized. The complete extraction for the OH-PAHs at a level of 40 ng·mL−1 and by using 4 mg sorbent is completed within 3 min. With an enzymatic hydrolyzed urine sample loading volume of 2 mL, enhancement factors in the range of 9–10, and a limit of detection (at S/N = 3) of 0.08 ng·mL−1 were achieved. The method showed a linear response in the 0.25–250 ng·mL−1 hydroxy-PAH concentration range, and intra-day and inter-day precisions are 1.5–7.7% and 2.2–8.7%, respectively. The recovery from spiked urine samples ranged from 90.1% to 102%. The sorbent was stable over 10 successive cycles of extraction/desorption of urine sample without significant loss of extraction efficiency. The method was successfully applied for the determination of OH-PAHs in urine samples of smoking volunteers.

The original version of this article unfortunately contained a mistake. In the Abstract section the sentence "Furthermore, the drug release mechanism was investigated by kinetic models and a first-order relationship was concluded, which indicated that the drug release is a simple diffusion process cohydroxyapatite/methotrexate complexntrolled by gradient drug concentration." was wrong. It should read as "Furthermore, the drug release mechanism was investigated by kinetic models and a first-order relationship was concluded, which indicated that the drug release is a simple diffusion process controlled by gradient drug concentration."

Carbon nitride (CN) and Au supported CN (Au/CN) were designed in this work to enhance the chemiluminescence (CL) intensity of Ce (IV) – Na2SO3 system. The results showed that the CL strength of Ce (IV) – Na2SO3 system could be increased by 250 times due to the catalytic effect of Au/CN. The powerful catalytic effect of Au/CN is attributed to the production of more ROS, which produces more SO2* and increases CL intensity. Based on the quenching effect of reduced glutathione (G-SH) on Ce (IV) – Na2SO3 – Au/CN system, a CL probe based on Ce (IV) – Na2SO3 -Au/CN system was designed to detect G-SH. It was indicated that the CL sensor exhibited excellent G-SH detection performance with a detection limit of 5.5 nM and a linear range from 0.026 to 217 μM. Compared with other methods, this work has a lower detection limit and a wider detection range.

Monoclinic BiVO4 photocatalyst was successfully synthesized by hydrothermal method under appropriate temperature. The photocatalytic performance of BiVO4 was improved by calcining at appropriate temperature. The structural and morphological properties of the synthesized BiVO4 photocatalysts were characterized by X-ray diffraction (XRD) and scanning electron microscopy (SEM), respectively. It is confirmed that the photocatalytic activity of the prepared catalysts was evaluated by the photodegradation of RhB under visible-light irradiation. BiVO4 calcined under appropriate temperature exhibited higher photocatalytic activity than uncalcined BiVO4 under visible light irradiation because calcination might effectively increases the purity of monoclinic bismuth vanadate.

In this study, a series of monoclinic BiVO4 photocatalysts were successfully synthesised by the sol–gel method by varying pH and molar concentration. The structural and morphological properties of the synthesised BiVO4 photocatalysts were characterised by X-ray diffraction and scanning electron microscopy, respectively. The photocatalytic activity of the catalysts was evaluated by the degradation of RhB under visible-light irradiation. The results indicate that at pH = 7, the catalysts showed the best photocatalytic activity, reaching up to 90.9%. Furthermore, at 0.2M concentration, the catalysts showed the best photocatalytic activity, reaching up to 89.4%. The catalysts synthesised at different pH and molar concentrations exhibited different photocatalytic activities under visible-light irradiation because different conditions led to different degrees of crystallinity and grain distributions of monoclinic BiVO4.

Effective exfoliation is crucial to the application of layered materials in many fields. Herein, we report a novel effective, scalable, and ecofriendly method for the exfoliation of lamellar HAp by glucosamine intercalation such that individual HAp nanoplates can be obtained. The as-exfoliated HAp nanoplates were characterized by Fourier transform infrared (FTIR), X-ray diffraction (XRD), transmission electron microscopy (TEM), and thermogravimetric (TG) analysis. It is found that the glucosamine intercalation not only results in complete exfoliation of lamellar HAp but also introduces the glucosamine molecules onto the surface of individual HAp nanoplates, thus obtaining separated glucosamine-grafted HAp nanoplates (Glu-HAps). Results from MTT assay demonstrate that glucosamine grafting on HAp nanoplates greatly improves the cell growth and proliferation as compared to nongrafted HAp counterparts.

Weak mechanical properties and poor protein adsorption capacity of sodium alginate (SA) limit its use in tissue engineering. In this study, glucosamine-grafted nanoplate-like hydroxyapatite (gHAp)–SA nanocomposite scaffolds were fabricated via solution mixture and freeze-drying method. Scanning electron microscopy, X-ray diffraction, Fourier transform infrared, and thermogravimetric analysis were used to characterize the gHAp/SA nanocomposites. The porosity, mechanical properties, and preliminary cell behaviour of the gHAp/SA nanocomposites were examined and compared with neat SA. The gHAp/SA nanocomposites show improved mechanical properties and superior cell viability to neat SA. Furthermore, both the mechanical and biological behaviours of the gHAp/SA nanocomposites are related to the content of gHAp. It has been demonstrated that the highly porous and mechanically robust gHAp/SA nanocomposite scaffolds hold promise in tissue engineering applications.

Energy-storage self-catalysis material that BiVO 4 assembled into porous Sr 2 MgSi 2 O 7 :Eu 2+ ,Dy 3+ was successfully synthesized by the impregnation method. Crystalline phases and microstructure of the energy-storage self-catalysis material were analyzed by X-ray diffraction, scanning electron microscopy, energy dispersive spectroscopy and atomic force microscope. Results indicated that BiVO 4 was assembled into Sr 2 MgSi 2 O 7 :Eu 2+ ,Dy 3+ pores physically. The photocatalysis property of the assembled sample was characterized through degrading the 5 ppm Rhodamine B solution and kinetics property was fitted according to the Langmuir–Hinshelwood formula. Results demonstrated that the assembled compounds exhibited higher photodegradation efficiency than the pure BiVO 4 no matter under the light or dark condition.

Porous Sr 2 MgSi 2 O 7 :Eu 2+ ,Dy 3+ energy storage carriers were successfully prepared via the sol-hydrothermal method. A thermogravimetric and differential thermal analysis was performed to investigate the influence of the sintering time and sintering temperature on the crystallization process of the porous Sr 2 MgSi 2 O 7 :Eu 2+ ,Dy 3+ . The phase composition and microstructure of the porous Sr 2 MgSi 2 O 7 :Eu 2+ ,Dy 3+ samples were analyzed by X-ray diffraction, scanning electron microscopy and transmission electron microscopy. Furthermore, the luminescence behavior was analyzed using a 3D photoluminescence scanner, excitation and emission spectra. The optical storage capability of the samples was investigated by studying the photoluminescence decay curves, which revealed that the afterglow time of the product could be improved by optimizing the annealing time and temperature.

In this study, Au-nanoparticle-supported crystalline ZnO (Au/ZnO) is found to be a simple and efficient photocatalyst for direct H2O2 synthesis in an aerated aqueous solution. Compared with widely studied Au-nanoparticle-supported anatase TiO2 photocatalyst, Au/ZnO shows almost one order of magnitude higher activity in H2O2 production. The site-specific deposition of smaller Au nanococatalyst on ZnO delivers best photocatalytic performance and the H2O2 production is relatively stable with a rate more than 1.5 mmol L−1 h−1. The electron spin resonance studies reveal that the H2O2 is produced through direct 2e− oxygen reduction over the optimized Au/ZnO photocatalyst.

In this study, g-C3N4/methotrexate (g-C3N4/MTX) nanohybrids were obtained via a self assembly method. XRD and TEM demonstrated that bulk g-C3N4 had been stripped into thin nanosheets with size range of 150-250 nm. FTIR investigation indicated that the self assembly of the hybrid was attributed to the hydrogen bond between g-C3N4 nanosheets and MTX molecules. It is confirmed by the UV-vis spectra that the hybrids can achieve a sustained drug release within long period for 70 h. Furthermore, the drug release mechanism was investigated by kinetic models and a first-order relationship was concluded, which indicated that the drug release is a simple diffusion process cohydroxyapatite/methotrexate complexntrolled by gradient drug concentration. Cell viability tests confirmed that g-C3N4 presented excellent biocompatibility and g-C3N4/MTX hybrids had obvious suppression efficiency on MG63 cells which showed a positive correlation to the drug concentration and incubation time.

Compared to two-dimensional (2D) conditions, investigation on gene transfection in three-dimensional (3D) conditions is much less extensive. In this work, lamellar nano-hydroxyapatite (L-HAp) with and without magnetism were used as the vectors and gene transfection in 2D and 3D cell culture was carried out and compared. We found that the transfection efficiency in 3D conditions was much higher than 2D cell culture. Additionally, magnetism enhanced transfection efficiency under both 2D and 3D conditions. The findings presented in this study demonstrated that the magnetic L-HAp could be a promising vector in 3D gene transfection.

Graphene oxide (GO) and hydroxyapatite (HAp) are frequently used as reinforcements in polymers to improve mechanical and biological properties. In this work, novel porous hybrid nanocomposites consisting of GO, HAp, and sodium alginate (SA) have been prepared by facile solution mixing and freeze drying in an attempt to obtain a scaffold with desirable mechanical and biological properties. The as-prepared porous GO/HAp/SA hybrid nanocomposites were characterized by SEM, XRD, FTIR, TGA, and mechanical testing. In addition, preliminary cell behavior was assessed by CCK8 assay. It is found that the GO/HAp/SA nanocomposites show improved compressive strength and modulus over neat SA and HAp/SA nanocomposites. CCK8 results reveal that the GO/HAp/SA nanocomposites show enhanced cell proliferation over neat SA and GO/SA nanocomposite. It has been demonstrated that GO/HAp20/SA holds promise in bone tissue engineering.

Hydroxyapatite (HAp) in the forms of fiber, needle, and whisker has been employed as fillers in polymer composites. Herein, nanoplate-like HAp synthesized by template-assisted self-assembly was used to reinforce polylactide (PLA) nanocomposites via the solution intercalation method. Dynamic and static mechanical properties and cytotoxicity of the as-prepared HAp/PLA nanocomposites were assessed in addition to characterizations by XRD, FTIR, and TGA. XRD analysis confirms the formation of exfoliated structure in the HAp/PLA nanocomposites. The HAp/PLA nanocomposites exhibit better static and dynamic mechanical properties than unreinforced PLA. Furthermore, the HAp/PLA nanocomposite with an optimum HAp content of 20wt% (20HAp/PLA) demonstrates not only the best mechanical performance but also the highest thermal stability among the nanocomposite samples. Cell studies using a mouse fibroblast cell line (L929) suggest that 20HAp/PLA shows excellent biocompatibility, which makes it a promising material for biomedical applications.

Magnetic lamellar hydroxyapatite (ML-HA) nanoparticles were synthesized by a template-assisted self-assembly process. The as-prepared ML-HA nanoparticles self-assembled under different conditions were characterized by XRD, TEM, cytotoxicity assessment, and DNA-loading and transfection efficiency measurements. We found that the structure and morphology of ML-HA were controlled by self-assembly conditions. The ML-HA synthesized in this work exhibited good biocompatibility. The DNA-loading capacity and ζ-potential of ML-HA were much lower in comparison to bare lamellar HA (L-HA) without magnetic nanoparticles. Despite that, the ML-HA with good lamellar structure showed 47% higher transfection efficiency than L-HA. Results suggested that the ordered lamellar structure is a key factor in controlling transfection efficiency and magnetization is an effective way of improving the transfection efficiency of lamellar HA. Mechanisms were proposed to interpret these experimental results. It is demonstrated that the ML-HA may be a promising gene vector to deliver DNA into the cells effectively and safely.

Lamellar hydroxyapatite (L-HAp) nanoplates of varying structure and morphology were synthesized by changing the template synthesis conditions including content of template agent and calcium and phosphate precursors. The as-prepared L-HAp nanoplates were characterized by XRD, TEM, and zeta potential analyses and their cytoxicity, DNA loading capacity, and gene transfection efficiency were evaluated. Results showed that loading of template agent and concentration of precursors had significant effects on the structure and morphology of L-HAp nanoplates. The L-HAp nanoplates with good lamellar structure could allow the intercalation of DNA molecules into the gallery of L-HAp and thus exhibited higher DNA loading capacity and transfection efficiency. It has been demonstrated that the structure and morphology of L-HAp nanoplates can be controlled by adjusting processing variables and that the L-HAp nanoplates with good lamellar structure has great potential as a gene delivery vector in non-viral based therapy.

In this study, for the first time, a laminated hydroxyapatite (HAp)/ methotrexate (MTX) complex was synthesized by in situ method using polyethylene glycol (PEG, MW8000) as template. Scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR) and UV–vis spectrophotometer were used to investigate the morphology, interaction and drug release property of synthesized HAp/MTX complex. SEM investigation indicated that laminated HAp/MTX complex with size ranging of 150–200 nm was obtained in the present of PEG molecules. The interaction between COO − of MTX and Ca 2+ of HAp was confirmed by FTIR investigation. In vitro drug release test indicated that the complex exhibits slow drug release ability which attributed to the laminated structure and interaction between MTX and HAp. Furthermore, it is confirmed that the drug release kinetic fitted Rigter-Pappas-order equation best which indicated that the drug release mechanism is a combination of MTX diffusion and HAp/MTX complex dissolution.

In this study, morphology effect of nano-hydroxyapatite as a drug carrier was investigated for the first time. Hydroxyapatite/methotrexate (HAp/MTX) hybrids with different morphologies were successfully prepared in situ using polyethylene glycol (PEG) as a template. SEM, TEM, XRD and FTIR results confirmed that the hybrids of different morphologies (laminated, rod-like and spherical) with similar phase composition and functional groups were obtained by changing the preparation parameters. UV-Vis spectroscopy was used to identify the drug loading capacity and drug release mechanism of the three hybrids with different morphologies. It is concluded that the laminated hybrid exhibits a higher drug loading capacity compared to the other two hybrids, and all the three hybrids showed a sustained slow release which were fitted well by Bhaskar equation. Additionally, the result of in vitro bioassay test confirms that the inhibition efficacy of the three hybrids showed a positive correlation to the drug loading capacity.

ZnO–B2O3–SiO2:Mn2+ (ZBSM) optical-storage glass–ceramics doped with ZnF2 were successfully prepared via sol–gel method. The effects of ZnF2 additive on the preparation of glass–ceramics were analyzed by differential scanning calorimetry. X-ray diffraction analysis, scanning electron microscopy and energy dispersive spectroscopy were employed to investigate the mineralogical and micro-structural characteristics of ZBSM (ZnF2) optical-storage glass–ceramics. Optical storage properties of the samples were measured through photoluminescence, long-lasting phosphor (LLP) decay curves and thermo-luminescence (TL). LLP decay curves demonstrated that lower phonons energy of F− could generate more stable metastable energy. TL spectra illustrated that the sample with 20 mol% ZnF2 content showed the best performance.

ZnBr 2 -doped ZnO–B 2 O 3 –SiO 2 :Mn 2+ (ZBSM) optical-storage glass-ceramics were successfully prepared by a sol–gel method. The crystalline phase and microstructure of ZBSM were analyzed by X-ray diffraction, Fourier transform infrared spectroscopy, scanning electron microscopy, and energy dispersive spectroscopy. The addition of ZnBr 2 influenced the crystallization of the ZBSM glass-ceramics. Moreover, the effects of ZnBr 2 additive on the preparation of glass-ceramics were analyzed by differential scanning calorimetry. The optical storage properties of the samples were investigated by photoluminescence spectroscopy, long-lasting phosphor (LLP) decay curves, and thermoluminescence (TL) spectroscopy. The LLP decay curves show that the lower phonon energy of Br − ions generates more stable metastable energy. The TL spectra and Gaussian fitting indicate that the sample with 20 mol% ZnBr 2 content exhibited the best performance.

Hydroxyapatite nanoparticles have been reported to exhibit potent anti-tumor effects in some cancer cells. In our previous study, we have successfully synthesized two types of hydroxyapatite nanoparticles, laminated hydroxyapatite (L-HAp) and laminated magnetic hydroxyapatite (LM-HAp). In this study, we wanted to investigate the effects of L-HAp and LM-HAp with various concentrations on human breast cancer MDA-MB-231 cells. Cell proliferation was assessed with a MTT colorimetric assay. Scratch and adhesion assays were used to detect the effects of these two materials on migration and adhesion. The expressions of integrin β1 and Akt were measured by Western blotting. Our results showed that L-HAp and LM-HAp had little cell cytotoxicity and significantly reduced cell mobility and adhesion. LM-HAp showed greater inhibitor ability on migration and adhesion of MDA-MB-231 cells. Moreover, results from western blotting showed that L-HAp and LM-HAp impacted the phosphorylation of integrin β1, but showed no regular impact on Akt. This study suggests that L-HAp and LM-HAp may be potential anti-tumor and delivery system for breast cancer therapy.

Two-dimensional layered materials exhibit desired functionalities when being used as gene delivery materials. In this study, a novel gene delivering vector, lamellar hydroxyapatite (HAp)/DNA nanohybrid was prepared. The structure of HAp/DNA nanohybrid was investigated by X-ray diffraction (XRD), scanning electron microscopy (SEM) and transmission electron microscopy (TEM). Fourier transform infrared (FT-IR) spectroscopy analysis revealed that ion-exchange occurred during the process. Gel electrophoresis analysis confirmed that the lamellar HAp could protect DNA from degradation of DNase I and the protected DNA could be recovered readily under acid conditions. Furthermore, the integrity of released DNA was confirmed by UV–vis spectra.

Nanofibers exist widely in human tissue and designing three-dimensional (3-D) nanofibrous tissue engineering has important implications. For the first time to our knowledge, this article described the construction of 3-D nanofibrous carbon scaffolds for potential bone tissue regeneration which are composed of carbon nanofiber (CNF) and hydroxyapatite (HAp). CNFs were obtained by carbonization under inert conditions with 3-D bacterial cellulose nanofibers as starting carbon sources. The resulting CNFs showed 3-D fibrous structural features with diameter ranging from 10 to 20 nm. In vitro biomineralization process was performed on the surface-treated 3-D CNFs. The resultant CNF/HAp composites were investigated using scanning electron microscopy, transmission electron microcopy, Raman spectroscopy, and X-ray diffraction. The results showed that surface treatment of CNFs in nitric acid promoted the mineralization and changed the morphology of HAp formed on CNFs.

Nature has succeeded in creating numerous bionanocomposites such as bones and teeth consisting of nano-platelets and biopolymers. Understanding of the mechanisms of formation and of the relation between structure and properties is vital for development of new materials for biomedical and engineering applications. In this work, varying contents of nano-platelet-like hydroxyapatite (HAp) has been used to reinforce gelatin (Gel) to produce nanocomposites. The prepared HAp/Gel nanocomposites were characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM), Fourier transform infrared (FTIR) spectroscopy, and thermogravimetric (TG/DTG) analyses. XRD, TEM, and FTIR results confirm the synthesis of intercalated and exfoliated nanostructures depending on the amount of gelatin. TG results reveal that the intercalated HAp/gelatin nanocomposites show improved thermal properties as compared to pristine gelatin. The results reported here can be expanded to other HAp–polymer systems, thus paving a new way of designing and fabricating biomemitic nanocomposites for future engineering and particularly for biomedical applications. Copyright © 2010 John Wiley & Sons, Ltd.