Porous CaSiO3-CaSO(4)composite scaffolds were successfully prepared by 3D gel-printing (3DGP) technology in this study. In order to further improve the degradation performance of pure CaSiO(3)scaffolds, the effect of ...
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Porous CaSiO3-CaSO(4)composite scaffolds were successfully prepared by 3D gel-printing (3DGP) technology in this study. In order to further improve the degradation performance of pure CaSiO(3)scaffolds, the effect of different CaSO(4)doping contents on CaSiO3-CaSO(4)composite scaffolds was studied. The results show that when the porous composite scaffolds were placed in simulated body fluid (SBF) for 5 weeks, the weight loss rate was 2.41% (CaSiO3-1%CaSO4), 3.97% (CaSiO3-3%CaSO4), 4.18% (CaSiO3-5%CaSO4), 6.87% (CaSiO3-7%CaSO4), and 12.93% (CaSiO3-9%CaSO4), respectively, which could be concluded that CaSO(4)doping has a significant effect on improving the biodegradability of CaSiO(3)scaffolds. And CaSO(4)doping can also effectively improve the compressive strength of composite scaffolds and that of CaSiO3-3%CaSO(4)composite scaffolds was tested as 54.67 MPa, and the shrinkage rate of porous composite scaffolds was nearly 11.4%, which meets the application requirements of bone repairing engineering.
Gold nanoparticles (AuNPs), as one of the major tools of fluorescence-quenching sensors, have been widely used in biochemical analysis through fluorescence resonance energy transfer (FRET) effect. With the development...
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Gold nanoparticles (AuNPs), as one of the major tools of fluorescence-quenching sensors, have been widely used in biochemical analysis through fluorescence resonance energy transfer (FRET) effect. With the development of chemistry and biochemistry, reaction-based fluorescent sensors have attracted increasing attention because of their unique selectivity, high sensitivity and rapid detection. Here we report a click-induced fluorescencequenching sensor based on AuNPs for detection of copper ion (Cu2+) and ascorbic acid (AA). A fluorescent dye Rhodamine B-(CH2CH2O)4-azide (RB-PEG4-N3) is conjugated to the surface of AuNPs via Cu(I)-catalyzed azidealkyne cycloaddition (CuAAC) in the presence of Cu2+ and AA, leading to the fluorescence quenching of Rhodamine B. The sensor responds quickly (within less than 3 min). The fluorescent intensity linearly correlates with the concentration of Cu2+ in the range of 0-10(8) mu M. The limit of detection (LOD) for Cu2+ is 5.8 mu M. The concentration range for detection of AA is 0-3 mM. The LOD for AA is 0.13 mM. In addition, the application of the sensor is verified by performing detection in real samples such as fresh orange, juice, VC tablet, and lake water. This work expands the application of AuNPs-based fluorescence-quenching sensors for multi-component detection.
The detection of protease activity in the body plays a significant role in the early diagnosis of diseases. However, enzymes inevitably come into contact with various complex biological fluids in the body during the f...
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The detection of protease activity in the body plays a significant role in the early diagnosis of diseases. However, enzymes inevitably come into contact with various complex biological fluids in the body during the flow, which greatly increases the detection difficulty. Therefore, protease detection in vivo has great challenges. Herein, we report a new assay for detecting protease using capillary electrophoresis inside a capillary with semicircular bends. We first designed a peptide substrate, and then the peptide was self-assembled with quantum dots to form a QDs-peptide substrate. The capillary was bent to semicircular-shaped turns and served as a micro-reactor to allow protease and substrate react in it. Due to the different electrophoretic velocity, the protease and the substrate were mixed inside the bent capillary with sequential injections and the cleavage of the substrate can be detected using capillary electrophoresis combined with Forster resonance energy transfer technology. This novel assay will greatly expand the detection of enzyme activity in vivo.
Beta-phase gallium oxide (beta-Ga2O3) has exceptional electronic properties with vast potential in power and radio frequency electronics. Despite the excellent demonstrations of high-performance unipolar devices, the ...
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Beta-phase gallium oxide (beta-Ga2O3) has exceptional electronic properties with vast potential in power and radio frequency electronics. Despite the excellent demonstrations of high-performance unipolar devices, the lack of effective p-type dopants in beta-Ga2O3 has hindered the further development of Ga2O3-based bipolar devices. In this work, we applied the semiconductor grafting approach and fabricated monocrystalline Si/beta-Ga(2)O(3)p-n heterojunctions, of which the characteristics were systematically studied. The heterojunctions demonstrated a diode rectification over 1.3 x 10(7) at +/- 2 V with a diode ideality factor of 1.13. Furthermore, capacitance-voltage (C-V) measurement showed frequency dispersion-free characteristics from 10 to 900 kHz. The interface defect density (D-it) was calculated as 1-3 x 10(12)/cm(2) eV. Scanning transmission electron microscopy (STEM) and x-ray photoelectron spectroscopy (XPS) revealed that an ultrathin oxygen-rich layer existed on the Ga2O3 surface and later formed an ultrathin interfacial layer after bonding with Si. It is speculated that the excessive oxygen at the Ga2O3 surface enhanced the passivation of the Si dangling bonds and thus reduced D-it. This work improved our understanding of interface properties of the semiconductor grafting approach, providing useful guidance on the future development of Si/Ga2O3 heterojunction devices.
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