The Experts below are selected from a list of 6267 Experts worldwide ranked by ideXlab platform
Dang Yuan Lei - One of the best experts on this subject based on the ideXlab platform.
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water resistant perovskite Nanodots enable robust two photon lasing in aqueous environment
Nature Communications, 2020Co-Authors: Dang Yuan Lei, Wei Ren, Xuyun Guo, Ye Zhu, Andrey L Rogach, Manish Chhowalla, Alex K Y JenAbstract:Owing to their large absorption cross-sections and high photoluminescence quantum yields, lead halide perovskite quantum dots (PQDs) are regarded as a promising candidate for various optoelectronics applications. However, easy degradation of PQDs in water and in a humid environment is a critical hindrance for applications. Here we develop a Pb-S bonding approach to synthesize water-resistant perovskite@silica Nanodots keeping their emission in water for over six weeks. A two-photon whispering-gallery mode laser device made of these ultra-stable Nanodots retain 80% of its initial emission quantum yield when immersed in water for 13 h, and a two-photon random laser based on the perovskite@silica Nanodots powder could still operate after the Nanodots were dispersed in water for up to 15 days. Our synthetic approach opens up an entirely new avenue for utilizing PQDs in aqueous environment, which will significantly broaden their applications not only in optoelectronics but also in bioimaging and biosensing. Lead halide perovskite quantum dots (PQDs) promise applications in optoelectronics but are limited by sensitivity to wet environments. Here the authors develop a Pb-S bonding approach to synthesize PQDs@silica Nanodots that are capable of emitting and lasing in aqueous environments for long periods.
Wenjian Weng - One of the best experts on this subject based on the ideXlab platform.
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effects of rgd immobilization on light induced cell sheet detachment from tio2 Nanodots films
Materials Science and Engineering: C, 2016Co-Authors: Kui Cheng, Wenjian Weng, Jun Lin, Hongping Wan, Tiantian Wang, Huiming WangAbstract:Light-induced cell detachment is reported to be a safe and effective cell sheet harvest method. In the present study, the effects of arginine-glycine-aspartic acid (RGD) immobilization on cell growth, cell sheet construction and cell harvest through light illumination are investigated. RGD was first immobilized on TiO2 Nanodots films through simple physical adsorption, and then mouse pre-osteoblastic MC3T3-E1 cells were seeded on the films. It was found that RGD immobilization promoted cell adhesion and proliferation. It was also observed that cells cultured on RGD immobilized films showed relatively high level of pan-cadherin. Cells harvested with ultraviolet illumination (365 nm) showed good viability on both RGD immobilized and unmodified TiO2 nanodot films. Single cell detachment assay showed that cells detached more quickly on RGD immobilized TiO2 nanodot films. That could be ascribed to the RGD release after UV365 illumination. The current study demonstrated that RGD immobilization could effectively improve both the cellular responses and light-induced cell harvest.
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light induced cell detachment for cell sheet technology
Biomaterials, 2013Co-Authors: Yi Hong, Kui Cheng, Wenjian Weng, Huiming Wang, Jun LinAbstract:The phenomenon of light-induced cell detachment is reported. Mouse calvaria-derived, pre-osteoblastic (MC3T3-E1) cells were cultured on a TiO(2) nanodot-coated quartz substrate. After 20 min of UV365 illumination, over 90% of the cells would detach from the surface. Moreover, intact cell sheets could be obtained in the same way. It was found that the as-obtained cells showed good viability, and could be used for further culture processes and other applications. Also, biocompatibility and safety characterizations indicated that the use of TiO(2) Nanodots and UV365 illumination was safe for such cell detachment. It is suggested that adsorbed extracellular matrix proteins play key roles in developing cell sheets and ensuring biocompatibility. The present light-induced cell detachment method demonstrates a promising way for rapid cell/cell sheet harvesting.
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size and density controlled synthesis of tio2 Nanodots on a substrate by phase separation induced self assembly
Nanotechnology, 2009Co-Authors: Kui Cheng, Piyi Du, Ge Shen, Wenjian Weng, Chenlu Song, Gang XuAbstract:This work presents a facile way, i.e. phase-separation-induced self-assembly, to prepare TiO2 Nanodots on a substrate. This method induces convective flow in a spin-coated titanium tetrabutoxide (TBOT)/polyvinyl pyrrolidone (PVP)/ethanol liquid film through the Marangoni effect and turns TBOT into crystalline TiO2 Nanodots on a substrate after calcination. The size and density of the TiO2 Nanodots can be finely tailored by controlling the concentrations of TBOT and PVP in the precursor sol. The TiO2 nanodot-deposited surface showed a hydrophilic characteristic and the wettability was obviously improved by increasing nanodot size.
Kui Cheng - One of the best experts on this subject based on the ideXlab platform.
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effects of rgd immobilization on light induced cell sheet detachment from tio2 Nanodots films
Materials Science and Engineering: C, 2016Co-Authors: Kui Cheng, Wenjian Weng, Jun Lin, Hongping Wan, Tiantian Wang, Huiming WangAbstract:Light-induced cell detachment is reported to be a safe and effective cell sheet harvest method. In the present study, the effects of arginine-glycine-aspartic acid (RGD) immobilization on cell growth, cell sheet construction and cell harvest through light illumination are investigated. RGD was first immobilized on TiO2 Nanodots films through simple physical adsorption, and then mouse pre-osteoblastic MC3T3-E1 cells were seeded on the films. It was found that RGD immobilization promoted cell adhesion and proliferation. It was also observed that cells cultured on RGD immobilized films showed relatively high level of pan-cadherin. Cells harvested with ultraviolet illumination (365 nm) showed good viability on both RGD immobilized and unmodified TiO2 nanodot films. Single cell detachment assay showed that cells detached more quickly on RGD immobilized TiO2 nanodot films. That could be ascribed to the RGD release after UV365 illumination. The current study demonstrated that RGD immobilization could effectively improve both the cellular responses and light-induced cell harvest.
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light induced cell detachment for cell sheet technology
Biomaterials, 2013Co-Authors: Yi Hong, Kui Cheng, Wenjian Weng, Huiming Wang, Jun LinAbstract:The phenomenon of light-induced cell detachment is reported. Mouse calvaria-derived, pre-osteoblastic (MC3T3-E1) cells were cultured on a TiO(2) nanodot-coated quartz substrate. After 20 min of UV365 illumination, over 90% of the cells would detach from the surface. Moreover, intact cell sheets could be obtained in the same way. It was found that the as-obtained cells showed good viability, and could be used for further culture processes and other applications. Also, biocompatibility and safety characterizations indicated that the use of TiO(2) Nanodots and UV365 illumination was safe for such cell detachment. It is suggested that adsorbed extracellular matrix proteins play key roles in developing cell sheets and ensuring biocompatibility. The present light-induced cell detachment method demonstrates a promising way for rapid cell/cell sheet harvesting.
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size and density controlled synthesis of tio2 Nanodots on a substrate by phase separation induced self assembly
Nanotechnology, 2009Co-Authors: Kui Cheng, Piyi Du, Ge Shen, Wenjian Weng, Chenlu Song, Gang XuAbstract:This work presents a facile way, i.e. phase-separation-induced self-assembly, to prepare TiO2 Nanodots on a substrate. This method induces convective flow in a spin-coated titanium tetrabutoxide (TBOT)/polyvinyl pyrrolidone (PVP)/ethanol liquid film through the Marangoni effect and turns TBOT into crystalline TiO2 Nanodots on a substrate after calcination. The size and density of the TiO2 Nanodots can be finely tailored by controlling the concentrations of TBOT and PVP in the precursor sol. The TiO2 nanodot-deposited surface showed a hydrophilic characteristic and the wettability was obviously improved by increasing nanodot size.
Jinming Lin - One of the best experts on this subject based on the ideXlab platform.
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Enhancement of Ultraweak Chemiluminescence from Reaction of Hydrogen Peroxide and Bisulfite by Water-Soluble Carbon Nanodots
2016Co-Authors: Wei Xue, Zhen Lin, Hui Chen, Jinming LinAbstract:In this work, carbon Nanodots were synthesized through a novel solvothermal route, and the effects of carbon Nanodots on the ultraweak chemiluminescence (CL) reaction of hydrogen peroxide (H2O2) and sodium bisulfite (NaHSO3) were explored for the first time. It was found that the CL emission intensity of H2O2–HSO3– was significantly enhanced by carbon Nanodots: about 60-fold increase in the CL intensity was obtained. The enhanced CL was induced by the excited-state carbon Nanodots (CD*), which could be produced from the electron-transfer annihilation of positively charged carbon Nanodots (CD•+) and negatively charged carbon Nanodots (CD•–). Radical scavengers such as nitro blue tetrazolium chloride (NBT), sodium azide, thiourea, 5,5-dimethyl-1-pyrroline N-oxide, and ascorbic acid were used to study the intermediate species. The intermediate radicals generated during the reaction of H2O2 and NaHSO3, such as hydroxide radical (•OH), sulfate anionic radical (SO4•–), superoxide anionic radical (•O2–), and sulfur trioxide anionic radical (•SO3–), were key species for producing CD•+ and CD•–. The CL enhancement mechanism was proposed based on the results of the CL emission spectra, fluorescence spectra, and electron spin resonance (ESR) spectra. The CL properties of carbon Nanodots will provide a new route to study the novel materials and broaden the use of them in many fields, such as chemistry, biology, microbiology, and biochemistry
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enhancement of ultraweak chemiluminescence from reaction of hydrogen peroxide and bisulfite by water soluble carbon Nanodots
Journal of Physical Chemistry C, 2011Co-Authors: Wei Xue, Zhen Lin, Hui Chen, Jinming LinAbstract:In this work, carbon Nanodots were synthesized through a novel solvothermal route, and the effects of carbon Nanodots on the ultraweak chemiluminescence (CL) reaction of hydrogen peroxide (H2O2) and sodium bisulfite (NaHSO3) were explored for the first time. It was found that the CL emission intensity of H2O2–HSO3– was significantly enhanced by carbon Nanodots: about 60-fold increase in the CL intensity was obtained. The enhanced CL was induced by the excited-state carbon Nanodots (CD*), which could be produced from the electron-transfer annihilation of positively charged carbon Nanodots (CD•+) and negatively charged carbon Nanodots (CD•–). Radical scavengers such as nitro blue tetrazolium chloride (NBT), sodium azide, thiourea, 5,5-dimethyl-1-pyrroline N-oxide, and ascorbic acid were used to study the intermediate species. The intermediate radicals generated during the reaction of H2O2 and NaHSO3, such as hydroxide radical (•OH), sulfate anionic radical (SO4•–), superoxide anionic radical (•O2–), and sul...
Alex K Y Jen - One of the best experts on this subject based on the ideXlab platform.
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water resistant perovskite Nanodots enable robust two photon lasing in aqueous environment
Nature Communications, 2020Co-Authors: Dang Yuan Lei, Wei Ren, Xuyun Guo, Ye Zhu, Andrey L Rogach, Manish Chhowalla, Alex K Y JenAbstract:Owing to their large absorption cross-sections and high photoluminescence quantum yields, lead halide perovskite quantum dots (PQDs) are regarded as a promising candidate for various optoelectronics applications. However, easy degradation of PQDs in water and in a humid environment is a critical hindrance for applications. Here we develop a Pb-S bonding approach to synthesize water-resistant perovskite@silica Nanodots keeping their emission in water for over six weeks. A two-photon whispering-gallery mode laser device made of these ultra-stable Nanodots retain 80% of its initial emission quantum yield when immersed in water for 13 h, and a two-photon random laser based on the perovskite@silica Nanodots powder could still operate after the Nanodots were dispersed in water for up to 15 days. Our synthetic approach opens up an entirely new avenue for utilizing PQDs in aqueous environment, which will significantly broaden their applications not only in optoelectronics but also in bioimaging and biosensing. Lead halide perovskite quantum dots (PQDs) promise applications in optoelectronics but are limited by sensitivity to wet environments. Here the authors develop a Pb-S bonding approach to synthesize PQDs@silica Nanodots that are capable of emitting and lasing in aqueous environments for long periods.
