20 results on '"Xu, Huo"'
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2. Lighting up Lipidic Nanoflares with Self-Powered and Multivalent 3D DNA Rolling Motors for High-Efficiency MicroRNA Sensing in Serum and Living Cells
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Li, Chan, Xue, Guohui, Wu, Rong, Zhang, Jing, Cheng, Yinghao, Huang, Guoqiao, Xu, Huo, Song, Qiufeng, Cheng, Ruize, Shen, Zhifa, and Xue, Chang
- Abstract
Intelligent DNA nanomachines are powerful and versatile molecular tools for bioimaging and biodiagnostic applications; however, they are generally constrained by complicated synthetic processes and poor reaction efficiencies. In this study, we developed a simple and efficient molecular machine by coupling a self-powered rolling motor with a lipidic nanoflare (termed RMNF), enabling high-contrast, robust, and rapid probing of cancer-associated microRNA (miRNA) in serum and living cells. The lipidic nanoflare is a cholesterol-based lipidic micelle decorated with hairpin-shaped tracks that can be facilely synthesized by stirring in buffered solution, whereas the 3D rolling motor (3D RM) is a rigidified tetrahedral DNA scaffold equipped with four single-stranded “legs” each silenced by a locking strand. Once exposed to the target miRNA, the 3D RM can be activated, followed by self-powered precession based on catalyzed hairpin assembly (CHA) and lighting up of the lipidic nanoflare. Notably, the multivalent 3D RM that moves using four DNA legs, which allows the motor to continuously and acceleratedly interreact with DNA tracks rather than dissociate from the surface of the nanoflare, yielded a limit of detection (LOD) of 500 fM at 37 °C within 1.5 h. Through the nick-hidden and rigidified structure design, RMNF exhibits high biostability and a low false-positive signal under complex physiological settings. The final application of RMNF for miRNA detection in clinical samples and living cells demonstrates its considerable potential for biomedical imaging and clinical diagnosis.
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- 2024
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3. Target-Induced Stepwise Disintegration of Starlike Branched and Multiplex Embedded Systems for Amplified Detection of Serum MicroRNA
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Xue, Guohui, Cheng, Yinghao, Xu, Huo, and Xue, Chang
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DNA nanotechnology has shown great promise for biosensing and molecular recognition. However, the practical application of conventional DNA biosensors is constrained by inadequate target stimuli, intricate design schemes, multicomponent systems, and susceptibility to nuclease degradation. To overcome these limitations, we present a class of starlike branched and multiplex embedded system (SBES) with an integrated functional design and cascade exponential amplification for serum microRNA (miRNA) detection. The DNA arms can be integrated into an all-in-one system by surrounding a branch point, with each arm endowed with specific functionalities by embedding different DNA fragments. These fragments include a segment complementary to the target miRNA for the recognition element, palindromic tails for self-primed polymerization, and a region with the same sequences as the target serving as the target analogue. Upon exposure to a target miRNA, the DNA arms unwind in a stepwise manner through palindrome-mediated dimerization and polymerization. This enables target recycling for subsequent reactions while releasing the target analogue to generate a secondary response in a feedback manner. A comparative analysis illustrates that the signal-to-noise ratio (SNR) of a full SBES with a feedback strategy is approximately 250% higher than the system without a feedback design. We demonstrate that the four-arm 4pSBES has the benefits of multifunctional integration, enhanced sensitivity, and low false-positive signals, which makes this approach ideally suited for clinical diagnosis. Moreover, an upgraded SBES with additional DNA arms (e.g., 6pSBES) can be constructed to allow multifunctional extension, offering unprecedented opportunities to build versatile DNA nanostructures for biosensing.
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- 2023
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4. Branch-Shaped Trapping Device Regulates Accelerated Catalyzed Hairpin Assembly and Its Application for MicroRNA In Situ Imaging.
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Xu, Huo, Zheng, Yanhui, Chen, Danlong, Cheng, Yinghao, Fang, Xiaojun, Zhong, Chunlian, Huang, Xinmei, Huang, Qi, Xu, Jiawei, Xu, Jianguo, and Xue, Chang
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- 2023
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5. Branch-Shaped Trapping Device Regulates Accelerated Catalyzed Hairpin Assembly and Its Application for MicroRNA In Situ Imaging
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Xu, Huo, Zheng, Yanhui, Chen, Danlong, Cheng, Yinghao, Fang, Xiaojun, Zhong, Chunlian, Huang, Xinmei, Huang, Qi, Xu, Jiawei, Xu, Jianguo, and Xue, Chang
- Abstract
Enzyme-free DNA strand displacement process is often practical when detecting miRNAs expressed at low levels in living cells. However, the poor kinetics, tedious reaction period, and multicomponent system hamper its in vivo applications to a great extent. Herein, we design a branch-shaped trapping device (BTD)-based spatial confinement reactor and applied it for accelerated miRNA in situ imaging. The reactor consists of a pair of trapped probe-based catalyzed hairpin assembly (T-CHA) reactions attached around the BTD. The trapping device naturally offered CHA reactions a good spatial-confinement effect by integrating the metastable probes (MHPa and MHPb) of the traditional CHA with the four-branched arm of BTD, which greatly improved the localized concentration of probes and shortened their physical distance. The autonomous and progressive walk of miRNA on the four-arm nanoprobes via T-CHA can rapidly tie numerous four-arm nanoprobes into figure-of-eight nanoknots (FENs), yielding strong fluorescence that is proportional to the miRNA expression level. The unique nanoarchitecture of the FEN also benefits the restricted freedom of movement (FOM) in a confined cellular environment, which makes the system ideally suitable for in situ imaging of intracellular miRNAs. In vitro and in situ analyses also demonstrated that the T-CHA overall outperformed the dissociative probe-based CHA (D-CHA) in stability, reaction speed, and amplification sensitivity. The final application of the T-CHA-based four-arm nanoprobe for imagings of both cancer cells and normal cells shows the potential of the platform for accurately and timely revealing miRNA in biological systems.
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- 2023
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6. Surface topography of nanoplastics modulates their internalization and toxicity in liver cellsElectronic supplementary information (ESI) available: Details on the size distribution of the synthesized AIE-NPs, normalized PL intensity of 10 mg L−1of AIE-NPs, aggregation kinetics of AIE-NPs within 24 h exposure, infrared spectra of AIE-NPs1 after HDS treatment for different durations, cytotoxicity of AIE-NPs after 24 h exposure, the intracellular patterns of AIE-NPs1-1 to AIE-NPs1-3, the intracellular patterns of AIE-NPs2-1 to AIE-NPs2-3, the impact of different endocytosis inhibitors (NaN3, MDC and FC) on the cellular accumulation of AIE-NPs1-1 to AIE-NPs 1-4 and AIE-NPs2-4 and the percentage of cells in live, necrotic, early apoptosis and late apoptosis after the cell was exposed to the AIE-NPs1 or without any AIE-NP exposure. See DOI: https://doi.org/10.1039/d3en00347g
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Yan, Neng, Wang, Yuhuai, Wong, Tin Yan, Hu, Yubing, Xu, Huo, Alessandro, Parodi, Pan, Ke, Liu, Jingjing, Lam, Henry, Tang, Ben Zhong, and Shi, Jianbo
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Though hepatotoxicity induced by the ubiquitous and potentially ingested nanoplastics (NPs) has been extensively studied, limited attention has been given to the role of NPs' surface topography. Since these ingested NPs pass through the human digestive system (HDS) before reaching the liver, their surface properties are altered, which affects their interactions with the organ. Herein, we prepared two different-sized aggregation-induced emission fluorogen-incorporated NPs (AIE-NPs) with diverse surface roughness by exposing NPs to the HDS for different durations. The HDS environment could effectively alter the surface roughness of the AIE-NPs, leading to an extended specific surface area and decreased hydrophobicity. Besides, roughening the NPs' surface facilitated their cellular internalization efficiency, mainly mediated by the specific surface area, which has been confirmed in vivoin a zebrafish model. After internalization, all these investigated AIE-NPs were consistently localized in lysosomes (Pearson's correlation coefficient > 0.8), suggesting that the surface roughness had negligible influence on their intracellular distribution pattern. The AIE-NPs with the rougher surface contributed to lysosomal alkalization and potentially caused lysosomal autophagy. Furthermore, exposure to AIE-NPs triggered reactive oxygen species (ROS) production, mitochondrial glutathione (mGSH) depletion and mitochondria dysfunction. The roughest AIE-NPs displayed the strongest cytotoxicity and sequentially led to cell apoptosis. Overall, this study highlighted the critical role of NP nanoscale surface topography, strengthening the understanding and assessment of NP toxicology.
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- 2023
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7. Copper Adsorption to Microplastics and Natural Particles in Seawater: A Comparison of Kinetics, Isotherms, and Bioavailability.
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Chen, Ciara Chun, Zhu, Xiaoshan, Xu, Huo, Chen, Fengyuan, Ma, Jie, and Pan, Ke
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- 2021
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8. Copper Adsorption to Microplastics and Natural Particles in Seawater: A Comparison of Kinetics, Isotherms, and Bioavailability
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Chen, Ciara Chun, Zhu, Xiaoshan, Xu, Huo, Chen, Fengyuan, Ma, Jie, and Pan, Ke
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The growing use of plastics has led to microplastics (MPs) being ubiquitously distributed in marine environments. Although previous studies have emphasized MPs as important metal-transport vectors, few have considered the differences between these anthropogenic particles and their coexisting natural counterparts in sequestering metals in seawater. Here, we compared Cu adsorption to pristine and naturally aged MPs (polystyrene and polyethylene) with that to algae particles and sediments and assessed the bioavailability of the adsorbed Cu by a gut juice extraction assay. Adsorption kinetics and isotherms consistently showed that natural particles bound far more Cu to their surfaces than MPs. The rougher surfaces, greater specific surface areas, and lower ζ-potentials of natural particles contributed to their stronger Cu adsorption capacity than pristine or aged MPs. Natural particles also contained more diverse functional groups for binding Cu, with oxygen-containing groups playing a dominant role. Adsorbed Cu on natural particles was less extractable by sipunculan gut juice than that on MPs, indicating their higher Cu affinity. Overall, our study suggests that natural particles outcompete MPs in carrying metals in the water column and transferring them to marine organisms in today’s environmental context. This work provides new insights for assessing the risks of MPs in marine environments.
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- 2021
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9. Diatom frustules with different silica contents affect copepod grazing due to differences in the nanoscale mechanical properties
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Xu, Huo, Shi, Zhiyuan, Zhang, Xiaodong, Pang, Mengwen, Pan, Ke, and Liu, Hongbin
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The silica frustules of diatom are regarded as an important physical defense against predation. While the biogenic silica content of diatoms is a major factor controlling the ingestion rate of copepods, how it affects the three‐dimensional structure and the mechanical properties of the frustules, and consequently copepod grazing, has not been studied. In this study, the diatoms Thalassiosira weissflogiiand Amphora coffeaeformiswere grown under different light intensities to manipulate their cellular biogenic silica contents. This manipulation generated diatom cells with distinct nano‐structures and mechanical strengths. The diatoms were then fed to the copepod Paracalanus pravusto test the effect of biogenic silica contents on copepod feeding. We demonstrated that the copepods preferred the low‐silica cells of T. weissflogii, but showed a preference for the high‐silica cells of A. coffeaeformis. Atomic force microscopy and X‐ray photoelectron spectroscopy analyses revealed that the chemical composition and mechanical properties of diatom frustules varied with silica contents. High silica containing T. weissflogiihad higher frustule elasticity and hardness. In contrast, A. coffeaeformiscontaining more biogenic silica had lower frustule elasticity but silica level had little effect on the hardness of the frustule. Our results indicate that the nano‐structure and chemical properties of the frustules determine the mechanical strength of the diatom frustules. This nanoscale study improves our understanding of the relationship between diatom biogenic silica content and copepod grazing in marine planktonic food webs.
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- 2021
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10. Long cruising aptamer-albumin nanobots intelligently capture and restrain circulating tumor cells.
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Wang, Jie, Xu, Huo, Li, Shuhui, Lin, Min, Lu, Yusheng, Liu, Kuancan, Katanaev, Vladimir, Denisov, Evgeny V., and Jia, Lee
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BLOOD circulation ,METASTASIS ,BINDING energy ,APTAMERS ,CELL cycle ,PSYCHONEUROIMMUNOLOGY ,SERUM albumin ,BREAST - Abstract
Circulating tumor cells (CTC) are the root cause of life-threatening cancer metastases. The rare CTC cannot be specifically killed by anti-cancer agents without producing any side effects, nor be targeted-and-eradicated by antibody or aptamer complexes because of the complexes' limited circulating half-life in the blood owing to metabolism and immune clearance. Here, we build the biosafe and biostable aptamer-albumin nanobots that can cruise in the blood much long together with the CTC, resulting in the increased capture efficiency and specificity of the nanobots targeting CTC. The intelligent-recognizing unit of the novel nanobots is composed of three EpCAM-targeting aptamers (AP) that can specifically target breast CTC, and their sticky ends are completely closed to form the biostable circular trivalent aptamers (CTA). The binding energy, specificity and stability of the circular three arms CTA are significantly superior to their linear AP. After conjugating CTA to human serum albumin (CTA-HSA) by amination reaction, the blood circulation time of CTA-HSA in mice was significantly prolonged by 3 folds, resulting in the enhanced collision probability and increased capture efficiency of CTA-HSA to CTC. CTA-HSA can escape the immune clearance and inhibit adhesion/invasion and cell cycle of CTC, resulting in CTC apoptosis. This proof-of-concept study provides a promising nanobiomaterial for CTC-induced cancer metastases. [Display omitted] • The chemical coupling of CTA and HSA significantly improves the residence time of nanomaterials in the blood. • CTA is formed by completely closing the sticky ends of three aptamers, and its specificity and biological stability are significantly better than the original aptamer. • CTA-HSA can efficiently lock in and promote CTC apoptosis through its excellent long cycle and targeted specificity. • This work provides a promising nano-biomaterial for CTC-induced cancer metastases. [ABSTRACT FROM AUTHOR]
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- 2023
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11. Precision-Guided Missile-Like DNA Nanostructure Containing Warhead and Guidance Control for Aptamer-Based Targeted Drug Delivery into Cancer Cells in Vitro and in Vivo
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Ouyang, Changhe, Zhang, Songbai, Xue, Chang, Yu, Xin, Xu, Huo, Wang, Zhenmeng, Lu, Yi, and Wu, Zai-Sheng
- Abstract
It is crucial to deliver anticancer drugs to target cells with high precision and efficiency. While nanomaterials have been shown to enhance the delivery efficiency once they reach the target, it remains challenging for precise drug delivery to overcome the nonspecific adsorption and off-target effect. To meet this challenge, we report herein the design of a novel DNA nanostructure to act as a DNA nanoscale precision-guided missile (D-PGM) for highly efficient loading and precise delivery of chemotherapeutic agents to specific target cells. The D-PGM consists of two parts: a warhead (WH) and a guidance/control (GC). The WH is a rod-like DNA nanostructure as a drug carrier, whose trunk is a three-dimensionally self-assembled DNA nanoscale architecture from the programmed hybridization among two palindromic DNA sequences in the x–ydimension and two common DNA oligonucleotides in the zdirection, making the WH possess a high payload capacity of drugs. The GC is an aptamer-based logic gate assembled in a highly organized fashion capable of performing cell-subtype-specific recognition via the sequential disassembly, mediated by cell-anchored aptamers. Because of the cooperative effects between the WH and the GC, the GC logic gates operate like the guidance and control system in a precision-guided missile to steer the doxorubicin (DOX)-loaded DNA WH toward target cancer cells, leading to selective and enhanced therapeutic efficacy. Moreover, fluorophores attached to different locations of D-PGM and DOX fluorescence dequenching upon release enable intracellular tracing of the DNA nanostructures and drugs. The results demonstrate that by mimicking the functionalities of a military precision-guided missile to design the sequential disassembly of the GC system in multistimuli-responsive fashion, our intrinsically biocompatible and degradable D-PGM can accurately identify target cancer cells in complex biological milieu and achieve active targeted drug delivery. The success of this strategy paves the way for specific cell identity and targeted cancer therapy.
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- 2020
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12. HAMPT, A Novel Quadruple Drug Combination Designed for Cancer Metastatic Chemoprevention: From Hypothesis to Proof-of-concept
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Xu, Huo, Wan, Liyuan, Xu, Jianguo, Liu, Jian, Zheng, Ning, and Jia, Lee
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Background: Highly Active Metastasis Preventing Therapy (HAMPT) is a quardruple drug combination consisting of mifepristone, aspirin, lysine and doxycycline. Objective: Based on our previous study, here, we further proved that HAMPT could effectively and safely prevent colon cancer metastasis. Methods: It was specifically designed for synergistically controlling key cancer metastatic pathways. The dose of HAMPT was designed at lower than the pharmaceutically-recommended dose, and thus the sub-healthy cancer survivors may take HAMPT safely and for a long time for metastasis chemoprevention. Results: HAMPT within its effective concentration range (1-50 μg/mL) showed no cytotoxicity to colon cancer cells HT-29 and CT-26, but significantly inhibited adhesion and invasion of these colon cancer cell lines to human umbilical vascular endothelial cells (HUVECs), and to Matrigel. HAMPT exhibits a good adhesion inhibited ratio, suggesting that it functions primarily by inhibiting adhesion of the cancer cells to HUVECs, rather than killing the cancer cells. At low concentrations, HAMPT also inhibited cancer cell migration. Flow cytometry analysis revealed that HAMPT had no significant effect on cell cycle, but inhibited IL-1β-induced expression of both E-selectin of HUVECs and Sialyl-Lewis X of HT-29. The in vivo experiment showed that HAMPT suppressed metastasis of CT-26 cells to mouse lungs in a dose-dependent manner. In the mouse model, HAMPT showed advantages in preventing metastasis over other combinations. Conclusion: The present study demonstrated that HAMPT is a novel quadruple drug combination that can safely and effectively prevent cancer metastasis.
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- 2019
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13. Structure-switchable aptamer-arranged reconfigurable DNA nanonetworks for targeted cancer therapy.
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Wang, Zhenmeng, Lv, Jinrui, Huang, Hong, Xu, Huo, Zhang, Jingjing, Xue, Chang, Zhang, Songbai, and Wu, Zai-Sheng
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APTAMERS ,DOXORUBICIN ,NANONETWORKS ,TARGETED drug delivery ,CANCER treatment ,DNA ,DNA nanotechnology - Abstract
The structural DNA nanotechnology holds great potential application in bioimaging, drug delivery and cancer therapy. Herein, an intelligent aptamer-incorporated DNA nanonetwork (Apt-Nnes) is demonstrated for cancer cell imaging and targeted drug delivery, which essentially is a micron-scale pattern with the thickness of double-stranded monolayer. Cancer cell-surface receptors can make it perform magical transformation into small size of nanosheet intermediates and specifically enter target cells. The binding affinity of Apt-Nnes is increased by 3-fold due to multivalent binding effect of aptamers and it can maintain the structural integrity in fetal bovine serum (FBS) for 8 h. More interestingly, target cancer cells can cause the structural disassembly, and each resulting unit transports 4963 doxorubicin (Dox) into target cells, causing the specific cellular cytotoxicity. The cell surface receptor-mediated disassembly of large size of DNA nanostructures into small size of fractions provides a valuable insight into developing intelligent DNA nanostructure suitable for biomedical applications. An aptamer-incorporated DNA nanonetwork is designed to be disassembled by target cancer cells, and each resulting unit transports drugs into the cells for intelligent targeted drug delivery. [Display omitted] • A micron-scale DNA pattern is presented for cell imaging and targeted drug delivery. • Disassembly of large size of DNA nanostructures into the small size. • Multivalent binding effect of aptamers provides a 3-fold higher binding affinity. • DNA nanonetworks retain the structural integrity in fetal bovine serum (FBS) over 8 h. • Each nanosheet intermediate can transport 4963 doxorubicin (Dox) into target cells. [ABSTRACT FROM AUTHOR]
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- 2022
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14. Synthesis and Catalytic Properties of Cu2+ Complexes with 4-Amino-Antipyrine Schiff Bases in Dye Degradation
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Jiang, Yin Zhi, Zhao, Gong Cheng, Fu, Zhu Ting, and Xu, Huo Ying
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Four 4-aminoantipyrine Schiffbases HL
a , HLb , HLc , HLd and Le were synthesized and characterized from 4-aminoantipyrine and corresponding aromatic aldehydes. The reaction of the Schiffbaes with CuCl2 were studied. And five mononuclear Cu2+ complexes, CuLa. OH, CuLb. OH. H2 O, CuLc. OH, CuLd. OH and CuLe. (OH)2 . H2 O were obtained and characterized by IR spectra,UV-Vis spectra and elemental analysis. The catalytic degradation of acid blue 9 was investigated by UV-Vis spectra, using the five synthetic Schiff base copper complexes as oxidase model compound. It was found that the five complexes all have catalytic effect. The catalytic activity of the three complexes, CuLa. OH, CuLb. OH. H2 O and CuLc. OH are better. It was found that the catalytic properties of the three complexes were similar with the enzymatic properties. Then the Km of CuLa. OH, CuLb. OH. H2 O and CuLc. OH was deterrmined with Km =1.15×10- 2 , 4.79×10- 2 and 6.89×10- 2 mmol / L, respectively. It is showed that the CuLa. OH, CuLb. OH. H2 O and CuLc. OH could be used as oxidase model compounds to catalyze the acid blue 9 degradation. The products of the acid blue 9 degradation was analyzed by HPLC method. It was found the degradation product was maleic acid. The degradation mechanism of the acid blue 9 was deduced. And the catalytic cycle for enzyme model compounds was deduced. Three novel biomimetic catalysts with acid blue 9 degradation properties were obtained, which provides theoretical and experimental supports for a new dye removal technology.- Published
- 2015
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15. Face masks as a source of nanoplastics and microplastics in the environment: Quantification, characterization, and potential for bioaccumulation.
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Ma, Jie, Chen, Fengyuan, Xu, Huo, Jiang, Hao, Liu, Jingli, Li, Ping, Chen, Ciara Chun, and Pan, Ke
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MEDICAL masks ,N95 respirators ,MICROPLASTICS ,COVID-19 pandemic ,ENVIRONMENTAL health - Abstract
Billions of disposable face masks are consumed daily due to the COVID-19 pandemic. The role of these masks as a source of nanoplastics (NPs) and microplastics (MPs) in the environment has not been studied in previous studies. We quantified and characterized face mask released particles and evaluated their potential for accumulation in humans and marine organisms. More than one billion of NPs and MPs were released from each surgical or N95 face mask. These irregularly-shaped particles sized from c. 5 nm to c. 600 μm. But most of them were nano scale sized <1 μm. The middle layers of the masks had released more particles than the outer and inner layers. That MPs were detected in the nasal mucus of mask wearers suggests they can be inhaled while wearing a mask. Mask released particles also adsorbed onto diatom surfaces and were ingested by marine organisms of different trophic levels. This data is useful for assessing the health and environmental risks of face masks. The nanoplastics (NPs) and microplastics (MPs) released from face masks were detected both in human's nasal mucus and marine organisms. [Display omitted] • Face masks can release large numbers of nanoplastics (NPs) microplastics (MPs). • The middle layers of the masks had more NPs than the outer and inner layers. • Mask MPs were detected in the nasal mucus of mask wearers suggests they can be inhaled while wearing a mask. • Mask NPs/MPs also adsorbed onto diatom surfaces and were ingested by marine organisms of different trophic levels. One sentence summary: Large numbers of nanoplastics (NPs) and microplastics (MPs) were released from face masks, and they were detected both in human's nasal mucus and marine organisms. [ABSTRACT FROM AUTHOR]
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- 2021
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16. Synthesis and Dye Degradation Properties of Cu2+ Complexes with Benzimidazole Derivatives
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Jiang, Yin Zhi, Shi, Yong Qiang, Tian, Lian Zhu, and Xu, Huo Ying
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Six benzimidazole derivatives were synthesized and charactrized by IR spectra, 1H-NMR spectra and MS spectra. The coordination reaction of the derivatives with CuCl
2 . And six novel Cu (II) complexes with the derivatives were prepared and characterized by UV spectra, IR spectra and elemental analysis. The catalytic degradation of methyl orange aqueous solution was investigated using the complexes as catalysis in presence H2 O2 by HPLC method and Vis-spectrophotometry. The result of characterization showed that there are four coordination sites around Cu (II) in all complexes, which are respectively occupied by one sulfur atom (from the derivative), one nitrogen atom (from the derivative), one oxygen atom ( from the OH- ) and one chlor atom (from the Cl- ). The degradation of methyl orange indicated that all the complexes show the properties of enzyme activity. And the main degradation products determined were hydroquinone and maleic acid.- Published
- 2013
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17. Graphdiyne oxide and graphene oxide sense monovalent cations differently: The alkyne and alkene physicochemistry.
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Deng, Xiaoxiao, Xie, Huanzhang, Lin, Min, Liu, Huibiao, Li, Yuliang, Lu, Yusheng, Wang, Jie, Li, Yumei, Zhong, Chunlian, Xu, Huo, and Jia, Lee
- Subjects
MONOVALENT cations ,GRAPHENE oxide ,VAN der Waals forces ,ZETA potential ,COLLOIDAL stability - Abstract
The differences between graphdiyne oxide (GDYO) and graphene oxide (GO) in physicochemistry and functionalities are important for precisely selecting the most suitable carbon allotrope for specific proposes, and essential for our understanding of alkyne and alkene fundamentals. However, the precise distinctions between GDYO and GO in ion sieving and sensing are basically unknown. Here we show that GDYO senses monovalent cations differently from GO. The unique sp-hybridization in GDYO provides it with more affinity with H 2 O molecules and stronger Coulomb electrostatic repulsion to maintain zeta potential high enough to preserve its interfacial colloidal stability without changes in attachment kinetics in the presence of Na
+ and K+ . Na+ and K+ freely move through the rotatable triangular cavities of GDYO. By comparison, GO shows less H 2 O affinity and zeta potential. Colloidal GO aggregates with Na+ and K+ . Both GO and GDYO sense concentration changes of bivalent and trivalent ions, resulting in interfacial instability that reaches zeta potential plateaus within narrow lower ion concentrations due to electrostatic force and van der Waals force. The present study discovers characteristics of GDYO sp-hybridization and its role in sensing monovalent cations, and elucidates physicochemical differences between GDYO and GO in sensing ions. [Display omitted] • Graphdiyne oxide senses monovalent cations differently from graphene oxide. • The unique sp-hybridization endows graphdiyne oxide more affinity with H 2 O and stronger Coulomb electrostatic repulsion. • Physicochemical differences between graphdiyne oxide/alkyne and graphene oxide/alkene in sensing ions. [ABSTRACT FROM AUTHOR]- Published
- 2021
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18. Synthesis and Crystal Structure of a New Cu2+ Complex
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Xu, Huo Ying, Jiang, Yin Zhi, Zou, Yang, and Zhang, Lian Qun
- Abstract
(R,R)-N,N’-di-(4-hydroxylbenzal)-1,2-cyclohexanediamine Schiff base(H
2 L) was synthesized and characterized by 1H NMR spectra, MS spectra and IR spectra. And the coordination reaction of H2 L with chlorate of Cu(II) was studied. The reaction of H2L with CuII salt [CuCl2 ] generates a new compound, the title compound. The title compound was determined by IR spectra, elemental analysis and single-crystal X-ray diffraction. The title compound belongs to the monoclinic system, space group P2(1), with a = 6.6393(6)Å, b = 24.735(2)Å, c = 8.1128(7)Å, α=90.00 º, β=110.1670(10) º , γ=90.00 º, Z=2, V= 1250.60(19) Å3 , Dc=1.382 mg.m-3 , µ=1.020mm-1 ,F(000)=554, R=0.0351 and wR= 0.0887. There are five coordination sites around Cu2+ of the title compound, which are respectively occupied by one oxygen atom from one H2 O molecule and four nitrogen atoms from two 1,2-cyclohexanediamine molecules. The Cu atom and four chelating nitrogen atoms are coplanar. There exist rich intra-molecular H-bond and intermolecular H-bond, which result in a three dimensional net.- Published
- 2012
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19. Multiple isotopic compositions reveal complex nitrogen cycling in a subtropical estuary.
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Jiang, Hao, Ma, Jie, Xu, Huo, Xu, Zhifang, Liu, Wenjing, and Pan, Ke
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NITROGEN cycle ,TERRITORIAL waters ,BIODIVERSITY ,WATER ,FISH kills ,HYPOXIA (Water) ,ESTUARIES - Abstract
Nitrogen (N) pollution and the resulting eutrophication can have deleterious consequences on estuaries, such as hypoxia, fish kills, and loss of biotic diversity. An understanding of N sources and cycling in estuaries is fundamental to determining how to effectively manage these ecologically and commercially important areas. We applied a multiple-isotopic approach to examine the transformations and sources of the N pools in the Pearl River Estuary (PRE) during winter. The surface water in the West PRE was characterized by low salinity and high NO 3
− , while that in the east had high salinity and low NO 3− . The NO 3− in the West PRE was largely regulated by a conservative mixing process. In contrast, assimilation and nitrification dominated in the East PRE, which was attributed to the long water-residence time. For the first time, the source contributions of NO 3− and NH 4+ were estimated by isotope mixing models. Our results suggest that river discharge and nitrification contributed 81% and 12% to the NO 3− pool, respectively. A major portion (68%) of the NH 4+ was from river discharge, with the remainder likely from sewage and the aquitard-aquifer system. Our study demonstrates that internal nitrification can potentially be of pivotal importance in determining the NO 3− level in an estuary and its export to coastal waters. Image 1 • This multiple-isotope study reveals the internal N cycling in a subtropical estuary. • Contrasting mixing and N cycling occur in the west and east parts of the estuary. • Conservative mixing regulated the NO 3− and NH 4+ concentrations in the west. • Assimilation and nitrification were more significant in the east. • Internal nitrification was an important source of NO 3− in the estuary. N cycling was confounded by hydrodynamics in the Pearl River Estuary and internal nitrification was present as a significant source of NO 3− in the estuary. [ABSTRACT FROM AUTHOR]- Published
- 2021
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20. Three CAG Trinucleotide Repeats on Chromosome 6 (D6S1014, D6S1015, and D6S1058) Are Not Expanded in 30 Families with Schizophrenia
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Ohara, Koichi, Tani, Kunihiko, Tsukamoto, Toshio, Ino, Atsushi, Nagai, Miho, Suzuki, Yasuo, Xu, Huo-Din, Xu, Dong-Sheng, Wang, Zu-Cheng, and Ohara, Kenshiro
- Abstract
Since 1991, more than five neuro-genetic disorders have been recognized to be caused by trinucleotide repeat expansions, and the list of such diseases should grow. The diseases are characterized clinically by the phenomenon of anticipation, i.e., worsening of the disease phenotype in successive generations with increasing trinucleotide repeat expansion. The presence of anticipation in familial schizophrenia has been suggested. Several studies have provided supportive evidence that the suceptability locus for schizophrenia is on chromosome 6. Therefore, we analyzed three CAG trinucleotide repeat clones D6S1014, D6S1015, and D6S1058 on chromosome 6, which are polymolphic in 30 families with schizophrenia. No unusually, long alleles that would suggest abnormal expansion of more than 35 trinucleotide repeats were observed for these genes. Also, no statistically significant differences were found between the offspring and parental generations of affected subjects or between the affected and unaffected subjects in families with schizophrenia. © 1997 American College of Neuropsyphopharmacology
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- 1997
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