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Qunfeng Fu Dr. Hongyu Li Dongban Duan Changlun Wang Siyong Shen Prof. Dr. Huimin Ma Prof. Dr. Zhibo Liu 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(48):21730-21736
Radiation-induced cleavage for controlled release in vivo is yet to be established. We demonstrate the use of 3,5-dihydroxybenzyl carbamate (DHBC) as a masking group that is selectively and efficiently removed by external radiation in vitro and in vivo. DHBC reacts mainly with hydroxyl radicals produced by radiation to afford hydroxylation at para/ortho positions, followed by 1,4- or 1,6-elimination to rescue the functionality of the client molecule. The reaction is rapid and can liberate functional molecules under physiological conditions. This controlled-release platform is compatible with living systems, as demonstrated by the release of a rhodol fluorophore derivative in cells and tumor xenografts. The combined benefits of the robust caging group, the good release yield, and the independence of penetration depth make DHBC derivatives attractive chemical caging moieties for use in chemical biology and prodrug activation. 相似文献
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Shaocheng Wang Siyong Lin Bo Xue Chenyu Wang Nana Yan Yueyan Guan Yuntao Hu Xuejun Wen 《Molecules (Basel, Switzerland)》2022,27(4)
Background: This study aimed to develop an ultrathin nanofibrous membrane able to, firstly, mimic the natural fibrous architecture of human Bruch’s membrane (BM) and, secondly, promote survival of retinal pigment epithelial (RPE) cells after surface functionalization of fibrous membranes. Methods: Integrin-binding peptides (IBPs) that specifically interact with appropriate adhesion receptors on RPEs were immobilized on Bruch’s-mimetic membranes to promote coverage of RPEs. Surface morphologies, Fourier-transform infrared spectroscopy spectra, contact angle analysis, Alamar Blue assay, live/dead assay, immunofluorescence staining, and scanning electron microscopy were used to evaluate the outcome. Results: Results showed that coated membranes maintained the original morphology of nanofibers. After coating with IBPs, the water contact angle of the membrane surfaces varied from 92.38 ± 0.67 degrees to 20.16 ± 0.81 degrees. RPE cells seeded on IBP-coated membranes showed the highest viability at all time points (Day 1, p < 0.05; Day 3, p < 0.01; Days 7 and 14, p < 0.001). The proliferation rate of RPE cells on uncoated poly(ε-caprolactone) (PCL) membranes was significantly lower than that of IBP-coated membranes (p < 0.001). SEM images showed a well-organized hexa/polygonal monolayer of RPE cells on IBP-coated membranes. RPE cells proliferated rapidly, contacted, and became confluent. RPE cells formed a tight adhesion with nanofibers under high-magnification SEM. Our findings confirmed that the IBP-coated PCL membrane improved the attachment, proliferation, and viability of RPE cells. In addition, in this study, we used serum-free culture for RPE cells and short IBPs without immunogenicity to prevent graft rejection and immunogenicity during transplantation. Conclusions: These results indicated that the biomimic BM-IBP-RPE nanofibrous graft might be a new, practicable approach to increase the success rate of RPE cell transplantation. 相似文献
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The surface modification of Ag/Ag2CO3 with Fe(III) ions has been achieved through simply photoreduction‐impregnation method. The obtained products were characterized by means of X‐ray diffraction (XRD), scanning electron microscopy (SEM), X‐ray photoelectron spectroscopy (XPS), and UV‐vis absorption spectroscopy. Under visible‐light irradiation (γ>420 nm), the Fe(III)/Ag/Ag2CO3 sample displays a higher photocatalytic activity and stability than pure Ag2CO3 and Ag/Ag2CO3 samples for the degradation of methyl orange (MO). The improved photocatalytic activity and stability of this ternary system could be ascribed to the synergetic effect between Ag nanoparticles and Fe(III) nanocluster. The metallic Ag nanoparticles cause an obviously enhanced visible‐light absorption to produce more photogenerated charges, while the Fe(III) works as an active site for the following oxygen reduction to reduce the recombination rate of photogenerated electrons and holes. 相似文献
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本文研究了内核经硫加金增感的内敏核壳乳剂的感光性能和离子性能。内核化学增感时Na2S2O3和AuCl3两者的加入量按一定比例增大时,内部感光度升高,表面感光度下降,离子电导率略有降低。内核化学增感时如果单独增加AuCl3的用量,内部感光度有所升高,表面感光性能基本不变,离子电导率略有下降。内核化学增感结束引入稳定剂583,可使内显灰雾明显降低,离子电导率也有所下降,核壳比增大造成内部感光度上升而表面感光度下降,离子电导率也有所下降。表面引入碘后,离子电导率明显上升。 相似文献
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本文采用X射线光电子能谱技术研究了两种照相明胶与化学增感剂相互作用的机理.当两种照相明胶样品在HAuCl4溶液中反应5min后,明胶中的蛋氨酸、蛋氨酸亚砜均被氧化为蛋氨酸砜.与此同时,明胶吸附的大部分Au3+被还原为Au+,并且Au+以络合形态存在于明胶之中.根据与AuCl3反应之后明胶中Au3+与Au+的比例,法国明胶的还原性略高于包头明胶.添加到明胶中的Na2S2O3能将明胶大分子所含的蛋氨酸亚砜全部还原为蛋氨酸.S2O32-、蛋氨酸和蛋氨酸砜可以稳定共存于明胶体系之中,外加的S2O32-的还原性高于明胶中蛋氨酸、蛋氨酸亚砜的还原性.添加Na2S2O3后的两种照相明胶均可以将其溶胀吸附的Au3+全部还原为胶态金.此时,参与氧化还原反应的主要基团是S2O32-而非明胶中的蛋氨酸残基.由于Na2S2O3的添加,照相明胶对AuCl3的还原能力增强. 相似文献
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Gu Siyong Hsieh Chien-Te Huq Mohammad Mahmudul Hsu Jo-Pei Ashraf Gandomi Yasser Li Jianlin 《Journal of Solid State Electrochemistry》2019,23(5):1399-1407
Journal of Solid State Electrochemistry - Magnesium-ion batteries are fabricated with MgCo2O4/graphite composites as the cathode material. MgCo2O4 nanoparticles are prepared using a... 相似文献