查找使用阿拉丁产品的科研文献

Pattern-based recognition of proteins by an array of fluorescent carbon-nanodot receptors

Yulin Liu,Shun Hu,Guoli Zhang,Qiuhua Wu,Guolin Zhang,Xue Liu

Protein types and concentrations in human body fluid environment have a direct correlation to health conditions, and can be used for primary screening and diagnostics of a great variety of diseases. Herein, we synthesized a series of fluorescent carbon nanodots (CDs) with various ratios of β-cyclodextrin doping, which can recognize proteins and adjust self-emission by combining both the cavity recognition effect of cyclodextrin and noncovalent bonding effect of carboxyl, amino and hydroxyl groups . The difference in β-cyclodextrin contents of various CDs will result in a differential response to various proteins, based on which a sensor array by four CDs was constructed to detect and discriminate six proteins with various subunit numbers. In order to improve the discriminative effect of the sensor array, CD-sensitive metal ions (Cu 2+ and Fe 3+ ) were introduced as sensing media to increase the action sites between the CDs and proteins, and these proteins were well discriminated by the [email protected] ion sensor array with a detection limit of 50 μM. The sensor array could work in physiological conditions (such as urine and serum) and realize multiple proteins detection. Combining with the good repeatable detection results and higher sensitivity, the sensor array based on the CDs and metal ions provides an efficient and accurate method to detect proteins, which is important for disease diagnosis through assessing protein levels.

An integrating photoanode consisting of BiVO4, rGO and LDH for photoelectrochemical water splitting

Lixia Sun,Jianhua Sun,Xiaojun Yang,Shouli Bai,Yongjun Feng,Ruixian Luo,Dianqing Li,Aifan Chen

The low carrier mobility of BiVO4 is a bottleneck that limits its charge transfer in bulk or on the surface. Herein, reduced graphene oxide (rGO) nanosheets as an effective electron mediator were successfully loaded on BiVO4 and NiFe-layered double hydroxides (NiFe-LDHs) were decorated on BiVO4/rGO heterojunctions by two facile electrodeposition methods to construct a triadic photoanode of BiVO4/rGO/NiFe-LDH for improvement of photoelectrochemical (PEC) water splitting efficiency of BiVO4. This photoanode significantly extends the absorption region of visible light, increases the photocurrent density, exhibits an onset potential with a significant cathodic shift, and enhances photon-to-electron conversion efficiency (IPCE) compared with the pristine BiVO4 photoanode. The enhancement of PEC properties benefits from the formation of p–n heterojunctions between rGO and BiVO4 and the use of NiFe-LDH as a cocatalyst for accelerating the kinetics of oxygen evolution from water.

PEGylated chitosan and PEGylated PLCL for blood vessel repair: An in vitro study

Anlin Yin,Xiaorong Lan,Weihua Zhuang,Zhonglan Tang,Yan Li,Yunbing Wang

In this study, we fabricated native tissue mimicking a bilayered small-diameter vascular graft based on PEGylated chitosan (PEG–CS) and poly(l-lactic acid-co-ε-caprolactone) (PLCL). PEG–CS possesses good hemocompatibility, and as the inner layer of a vascular graft, it is more likely to swell and deform to debris, causing a blood clot, so the PLCL was added to stabilize it. In order to optimize the performance of the inner layer, PEG–CS blends with different ratios of PLCL (P/C:PLCL) casting films were fabricated, and endothelial cell compatibility and hemocompatibility were tested. The outer layer of the graft was fabricated via electrospinning with PLCL blends with different ratios of water-soluble polyethylene glycol. After water treatment, we tested smooth muscle cell penetration. Designing a two-layer vascular graft structure with an inner layer of P/C:PLCL = 1:6 and an outer layer being composed of a PLCL blend with 12% polyethylene glycol offers very good hemocompatibility and fast cell growth and also reserves well mechanical properties with good cell infiltration. Therefore, this kind of graft has a high potential to be used as an artificial blood vessel.

Epsilon-negative behavior of BaTiO3/Ag metacomposites prepared by an in situ synthesis

Zhongyang Wang,Peitao Xie,Guohua Fan,Zidong Zhang,Yao Liu,Qilin Gu,Runhua Fan

Epsilon-negative behavior in metamaterials has attracted increasing attention recently. In this work, excessively percolating BaTiO 3 /Ag composites were synthesized by an in-situ preparation method to achieve negative permittivity. The epsilon-negative behavior is explained by low-frequency plasma oscillation of free electrons, which can be well fitted by the Drude model. Moreover, the negative permittivity of composites can be tuned by adjusting the content of randomly distributed Ag particles. The ac conductivity of excessively percolating BaTiO 3 /Ag composites shows a typical metal-like behavior. Furthermore, the investigation of reactance reveals that the inductive character derived from the conductive network is the main contributor to negative permittivity, as confirmed by the equivalent circuit analysis. This work provides a theoretical recipe for designing negative permittivity, supplements the family of metamaterials, and would further facilitate the practical applications of epsilon-negative materials in electromagnetic devices.

Facile loading carbon dots on Co3O4 as an enhanced oxygen reduction reaction catalyst

Xiaoyan Zhang,Xiumei Cheng,Feng Chen,Li Xu,Yaping Wang,Junchao Qian,Zhengying Wu,Qi Zhang

One of the crucial issues in fuel cells is to explore the highly-efficient, long-term stable and low-cost catalysts for the oxygen reduction reaction (ORR). Here, the carbon dots/Co 3 O 4 (CDs/Co 3 O 4 ) is reported as an effective electrocatalyst for ORR. The CDs/Co 3 O 4 was synthesized through an in-situ two-step heating strategy with the graphitic carbon nitride (g-C 3 N 4 ), cobalt nitrate hexahydrate and organic base as raw materials. The carbon dots (CDs) are derived from the C source of g-C 3 N 4 , which are in situ introduced into the Co 3 O 4 to form the CDs/Co 3 O 4 composite. Consequently, the introduction of CDs endows enhanced electrocatalytic activity of the CDs/Co 3 O 4 composite.

Stable, Bioresponsive, and Macrophage-Evading Polyurethane Micelles Containing an Anionic Tripeptide Chain Extender

Danxuan Fang,Menghan Pi,Zhicheng Pan,Nijia Song,Xueling He,Jiehua Li,Feng Luo,Hong Tan,Zhen Li

Polymeric nanocarriers have been extensively used in medicinal applications for drug delivery. However, intravenous nanocarriers circulating in the blood will be rapidly cleared from the mononuclear macrophage system. The surface physicochemical characterizations of nanocarriers are the primary factors to determine their fate in vivo, such as evading the reticuloendothelial system, exhibiting long blood circulation times, and accumulating in the targeted site. In this work, we develop a series of polyurethane micelles containing segments of an anionic tripeptide, hydrophilic mPEG, and disulfide bonds. It is found that the long hydrophilic mPEG can shield the micellar surface and have a synergistic effect with the negatively charged tripeptide to minimize macrophage phagocytosis. Meanwhile, the disulfide bond can rapidly respond to the intracellular reduction environment, leading to the acceleration of drug release and improvement of the therapeutic effect. Our results verify that these anionic polyurethane micelles hold great potential in the development of the stealth immune system and controllable intracellular drug transporters.

A turn-on luminescence probe for highly selective detection of an anthrax biomarker

Xiao Liu,Dong Chen,Chenchen Wang,Nianjuan Tian,Zhiqiang Li,Ying Zhang,Zhi-Jun Ding

Highly selective detection of Bacillus anthrax spores has attracted worldwide attention because Bacillus anthrax spores not only are harmful to the health of human beings and animals, but also can be used as biological warfare agents. Here, we report a simple platform by mixing EuCl 3 ·6H 2 O and sodium polyacrylate in aqueous solution and further investigate its luminescence response towards Bacillus anthrax biomarker dipicolinic acid (DPA) as a turn-on luminescence probe. Importantly, our probe has good sensitivity, lower detection limit, excellent selectivity as well as great anti-interference ability due to the great luminescence enhancement of Eu 3+ . Moreover, a test paper is constructed to realize the purpose of portable detection. These results indicate that our probe is an excellent candidate for sensing DPA.

An Ammonium-Formate-Driven Trienzymatic Cascade for ω-Transaminase-Catalyzed (R)-Selective Amination

Fei-Fei Chen,Yu-Hui Zhang,Zhi-Jun Zhang,Lei Liu,Jian-Ping Wu,Jian-He Xu,Gao-Wei Zheng

(R)-Amination mediated by (R)-specific ω-transaminases generally requires costly d-alanine in excess to obtain the desired chiral amines in high yield. Herein, a one-pot, trienzymatic cascade comprising an (R)-specific ω-transaminase, an amine dehydrogenase, and a formate dehydrogenase was developed for the economical and eco-friendly synthesis of (R)-chiral amines. Using inexpensive ammonium formate as the sole sacrificial agent, the established cascade system enabled efficient ω-transaminase-mediated (R)-amination of various ketones, with high conversions and excellent ee (>99%); water and CO2 were the only waste products.

An ultralight, supercompressible, superhydrophobic and multifunctional carbon aerogel with a specially designed structure

Sishi Long,Yunchao Feng,Faliang He,Shuaishuai He,Huachi Hong,Xuerui Yang,Lingling Zheng,Jian Liu,Lihui Gan,Minnan Long

Compressible and ultralight carbon aerogels are attractive due to its compressibility , elasticity and conductivity. However, it is still a great challenge to enrich the properties of carbon aerogel to meet various requirements. Herein, we report an untralight, supercompressible, fatigue resistant, superhydrophobic and fire-resistant and multifunctional CNF-GO/glucose-kaolin carbon aerogel (C-NGGK) carbon aerogel. To achieve such excellent performances, calcined GO , CNFs , glucose and kaolin are used for forming low-density and continuous wave-shape rGO layers, reinforcing the mechanical strength of carbon layers , realizing superelasticity and fatigue resistance and resulting in a superhydrophobic surface for C-NGGK, respectively. The as-prepared C-NGGK demonstrates excellent superhydrophobicity with the water contact angle (WCA) of 124.9°, and the absorption efficiency of the C-NGGK samples for different oils and organic solvents are 75–255 times their own weight. These advantages show that the C-NGGK can be an ideal candidate for oil/water separation. In addition, there is also the prospect to be used for pressure sensors , while other potential applications include three-dimensional electrode materials for supercapacitors and batteries , catalyst carriers and various wearable devices .

Highly efficient and selective recovery of gallium achieved on an amide-functionalized cellulose

Wanghuan Guo,Jinbo Zhang,Fan Yang,Fengzhi Tan,Zhigang Zhao

TiO2-B as an electron transporting material for highly efficient perovskite solar cells

Fengyan Xie,Jingwei Zhu,Yafeng Li,Deli Shen,Antonio Abate,Mingdeng Wei

The electron transporting layer plays an important role in charge extraction and transporting procedure for mesoscopic perovskite solar cells. Herein, the TiO 2 -B nanoparticles are used as an electron transporting material in perovskite solar cells for the first time which achieves a high efficiency of 18.83%. Furthermore, the effects of TiO 2 -B electron transporting layer on the nature of perovskite adsorption layer and the photovoltaic properties of devices are investigated in detail. As a consequence, the high efficiency can be ascribed to perovskite layer with a high crystallinity , resulting in suppressing charge recombination at interfaces, leading to favourable energy level alignment between perovskite and TiO 2 -B.

An injectable and self-healing novel chitosan hydrogel with low adamantane substitution degree

Cheng Liu,Liquan Yang,Liyuan Qiao,Chengde Liu,Manxia Zhang,Xigao Jian

Chitosan (CS) is a semi-natural polymer with supreme biological function, while the strong interchain hydrogen bonds cause poor water solubility and limit its broader use. To break the semi-rigid structure of CS, a kind of CS modified by adamantane (AD-CS) was successfully synthesized by amidation reaction with 1-(3-dimethylaminopropyl)-3-ethylcarbodiimide hydrochloride as catalyst. The chemical structure of AD-CS was characterized by Fourier transform infrared spectroscopy and 1 H NMR. The AD substitution degree of CS is around 2%, calculated by 1 H NMR. A soft and transparent hydrogel composed of hydrogen bonds was obtained directly by simply adding a certain amount of water under mild conditions. Rheological measurements were carried out to research the mechanism of hydrogel formation by measuring the influence of different additives and conditions on the AD-CS hydrogel. Reinforced hydrogels were prepared by freezing and thawing. The mechanical strength and self-healing property of reinforced and pristine hydrogels were assessed with an oscillatory rheometer. The modulus of the reinforced hydrogel was obviously enhanced without much loss of self-healing property. Other properties such as adhesion, injectability and temperature response were also studied. These injectable and self-healing hydrogels show potential value in medical care. Additionally, this is a new method to design CS hydrogels with their original interchain hydrogen bonds. © 2019 Society of Chemical Industry