ANALYTICAL CHEMISTRY
·
2020
·
IF 6.785
Kang Liu,Shuohan Huang,Danjun Fang
Here, a microelectrode approach is established to measure the flip-flop rate of cholesterol in plasma membranes at single living cells. The initial validation is performed in a modeled phospholipid bilayer positioned at an interconnecting hole between two compartments, in which cholesterol in one compartment diffuses into the other one through a flip-flop movement in the bilayer and is then detected by a cholesterol oxidase-modified microelectrode. As compared with the time (140 ± 28 s) for free cholesterol transport in absence of the bilayer, a prolonged time (702 ± 42 s) is needed to observe the current increase in the presence of the bilayer. The difference in the time (562 s) gives the estimated flip-flop time of cholesterol in the bilayer. The position of the microelectrode in contact with a living cell and the injection of cholesterol inside the cell are further applied to measure the cholesterol flip-flop in the plasma membrane. The average time (1183 ± 146 s) is obtained to observe an additional current increase at the microelectrode, which reflects the cholesterol flip-flop rate in plasma membranes in single living cells. All these results support the establishment of this microelectrode approach for the study of the cholesterol flip-flop process in lipid membranes.
研究领域:
生物化学
·
分析化学
·
细胞生物学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Journal of Physical Chemistry C
·
2019
·
IF 4.309
Yong-Hao Ma,Bolin Li,Jingjing Yang,Xiaofeng Han,Zhan Chen,Xiaolin Lu
Ion homeostasis regulated by diverse transport systems is important for cell functions, where the two major components of cell membranes, namely proteins and lipids, must play critical roles. The role of transport systems based on proteins, for example ion pumps and channels, has generally been acknowledged and studied in the past few decades, while the importance of lipid systems, for example lipid ion channels, has not been fully appreciated so far with the lack of detailed molecular-level information. Here, we applied sum frequency generation vibrational spectroscopy to investigate the lipid transmembrane movement, namely flip-flop, affected by metal ions for lipid bilayers, which is related to the cellular ion homeostasis. Metal ions in the same group (Ba2+, Sr2+, and Ca2+) but with different sizes were used; the distance between lipid molecules in a bilayer was also manipulated upon adjusting the surface pressure. We found that, on the one hand, there existed a match relationship between the metal ion size and the distance among the lipid molecules, which led to the significant decrease of the flip-flop rate for the lipid bilayer. On the other hand, the flip-flop process was accelerated when the metal ion size and the lipid distance were mismatched. This study highlights the ion size effects on the lipid transmembrane flip-flop rates, providing the inspiring clue for understanding the lipid function related to the cellular ion homeostasis.
研究领域:
生物物理学
·
细胞生物学
✓ 已验证
产品关联
DOI
高影响因子
Advanced Science
·
2024
·Vol. 11
·期 26
·2402824
·
IF 14.3
Chen Fei Dai,Qing Li Zhu,Olena Khoruzhenko,Michael Thelen,Huiying Bai,Josef Breu,Miao Du,Qiang Zheng,Zi Liang Wu
Creatures, such as Venus flytrap and hummingbirds, capable of rapid predation through snap-through transition, provide paradigms for the design of soft actuators and robots with fast actions. However, these artificial “snappers” usually need contact stimulations to trigger the flipping. Reported here is a constrained anisotropic poly( N -isopropylacrylamide) hydrogel showing fast snapping upon light stimulation. This hydrogel is prepared by flow-induced orientation of nanosheets (NSs) within a rectangular tube. The precursor containing gold nanoparticles is immediately exposed to UV light for photopolymerization to fix the ordered structure of NSs. Two ends of the slender gel are clamped to form a buckle with bistability nature, which snaps to the other side upon laser irradiation. Systematic experiments are conducted to investigate the influences of power intensity and irradiation angle of the laser, as well as thickness and buckle height of the gel, on the snapping behaviors. The fast snapping is further used to kick a plastic bead and control the switch state. Furthermore, synergetic or oscillated snapping of the gel with two buckles of opposite directions is realized by inclined irradiation of a laser or horizontal irradiation with two lasers, respectively. Such light-steered snapping of hydrogels should merit designing soft robots, energy harvests, etc.
研究领域:
软体机器人
·
材料科学
·
仿生学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
ADVANCED MATERIALS
·
2024
·Vol. 36
·期 28
·2314152
·
IF 27.4
Qing Li Zhu,Weixuan Liu,Olena Khoruzhenko,Josef Breu,Huiying Bai,Wei Hong,Qiang Zheng,Zi Liang Wu
Self-sustained motions are widespread in biological systems by harvesting energy from surrounding environments, which inspire scientists to develop autonomous soft robots. However, most-existing soft robots require dynamic heterogeneous stimuli or complex fabrication with different components. Recently, control of topological geometry has been promising to afford soft robots with physical intelligence and thus life-like motions. Reported here are a series of closed twisted ribbon robots, which exhibit self-sustained flipping and rotation under constant light irradiation. Both Möbius strip and Seifert ribbon robots are devised for the first time by using an identical hydrogel, which responds to light irradiation on either side. Experiment and simulation results indicate that the self-regulated motions of the hydrogel robots are related to fast and reversible response of muscle-like gel, self-shadowing effect, and topology-facilitated refresh of light-exposed regions. The motion speeds and directions of the hydrogel robots can be tuned over a wide range. These closed twisted ribbon hydrogels are further applied to execute specific tasks in aqueous environments, such as collecting plastic balls, climbing a vertical rod, and transporting objects. This work presents new design principle for autonomous hydrogel robots by benefiting from material response and topology geometry, which may be inspirative for the robotics community.
研究领域:
材料科学
·
生物工程
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Advanced Electronic Materials
·
2025
·
IF 5.3
Li Zhang,Zhaomeng Wang,Geng Wei,Puyue Xia,Sining Fan,Wenhao Zhang,Shaolong Tang
The preparation of conductive filler is a key technology in anisotropic conductive films preparation. In recent decades, research on the preparation of novel conductive particles has reached a bottleneck. Porous gold materials exhibit high compressibility, low density, and excellent conductivity. It is believed that using porous gold microspheres (PGMS) to supersede polymer composite conductive microspheres has the potential to prepare anisotropic conductive film (ACF) with better performance. However, preparing ultrafine (1–10 µm) PGMS remains challenging. Herein, the study presents a novel method for preparing PGMS with controllable particle size and high sphericity. Results show that porous gold microspheres ACF (PGMS-ACF), containing only 5 wt.% particles (size range 4.5–10.5 µm), achieves good conductivity when held at a pressure range of 0.05–0.6 MPa. Its compression ratio is between 33% and 71% at 0.3 MPa. The 4-point probe measurement shows a contact resistance as low as 10 mΩ in 2 mm 2 . Moreover, PGMS-ACF also exhibits a good linear relationship within 3.3 A. Compared to commercial polymer composite conductive microspheres ACF, PGMS-ACF offers a significant advantage in achieving a large compression ratio, which in turn leads to improved conductivity and reduces the need for precise sorting. The research provides a new approach for the preparation of novel ACF.
研究领域:
材料科学
·
电子工程
✓ 已验证
产品关联
DOI
高影响因子
SENSORS AND ACTUATORS B-CHEMICAL
·
2020
·
IF 7.1
Kun Zhou,Zhida Zhao,Pengbo Yu,Zheyao Wang
This paper presents a method of achieving high sensitivity for silicon nanowire (SiNW) field-effect transistor (FET) pH sensor by operating the FETs in both capacitive amplification mode and differential amplification mode. The capacitive amplification is implemented by employing an inversed double-gate configuration that uses the electrode immersed in a solution well etched from the backside of the sensor chip as the top gate and the SiNW metal gate as the back gate. This enables the threshold voltages of the FETs to be amplified through the ratio of the top gate capacitance to the back gate capacitance. The differential amplification is achieved by a readout circuit chip that is vertically integrated with the sensor chip using flip-chip bonding. This allows the back gate to be controlled independently by the circuits, such that the differential amplification that is originally applicable to single-gate FETs can be applied to double-gate FETs. By operating the dual amplifications simultaneously, a sensitivity of 720.7 mV/pH has been achieved in the pH range of 4−10. Small deviations between the SiNW pH sensor and a commercial pH meter in measuring phosphate buffer saline, bovine serum, and tap water demonstrate the capability of the SiNW pH sensor in measuring practical samples.
研究领域:
生物医学工程
·
微电子学
·
传感器技术
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF NANOSCIENCE AND NANOTECHNOLOGY
·
2021
·Vol. 21
·期 9
·4586-4595
·
IF 0
Wang Yun,Chen Zhangjian,Chen Shi,Zhuo Lin,Zhao Lin,Jia Guang
Titanium dioxide nanoparticles (TiO2 NPs) as food additives were widely found in various foodrelated products, especially in high-sugar foods. The daily intake of TiO2 NPs in the diet may therefore expose the small intestine to TiO2 NPs and affect its
physiological functions, including the absorption of nutrients. It is speculated that TiO2 may cause serious health hazards by increasing sugar uptake. To explore this possibility, transport of glucose from small intestine was studied using an everted gut sac model prepared from
small intestine of young healthy male SD rats. The translocation of TiO2 NPs and the morphological changes of small intestine were also observed after exposure of intestinal lumen to TiO2 NPs for 2 h. The results showed that TiO2 NPs can enter into enterocyte
but hardly cross the intestinal epithelium. No change on microstructure of gut epithelia and expression of glucose transporter was found, and there is no obvious impact on intestinal absorption and metabolism of glucose. These results suggest that short-term exposure to TiO2 NPs
has little influence on intestinal absorption of glucose. More attention should be paid to the chronic effect of dietary consumption of TiO2 NPs on nutrient absorption.
研究领域:
纳米技术
·
营养科学
·
毒理学
✓ 已验证
DOI
PubMed
CHEMICAL ENGINEERING JOURNAL
·
2025
·
IF 13.2
Junhui Wang,Jiajia Liao,Tongkun Zhu,Zhipeng Wang,Qiong Yang,Hongze Liu,Shijie Jia,Jin Huang,Sirui Zhang,Jiayi Hu,Jie Jiang,Limei Jiang,Yichun Zhou
Ferroelectric synaptic devices are pivotal in artificial intelligence applications, particularly for image recognition tasks. Their outstanding capabilities in neuromorphic information processing, biologically plausible signal emulation, and faithful neural mimicry render them indispensable. However, for HfO 2 -based ferroelectric synaptic devices, concurrently attaining high remnant polarization and rapid domain switching which are essential for high-speed processing and precise pattern recognition remains a formidable challenge. In this study, gradient Zn-doped HfCeO x (Zn: HCO) ferroelectric film was fabricated. It displays enhanced ferroelectric properties with a remnant polarization (2 P r ) reaching 77.2 µC/cm 2 . High-resolution transmission electron microscopy analyzes and phase-field simulations reveal that the gradient Zn doping induces a flexoelectric effect in HfCeO x thin films, which promotes the formation of the ferroelectric orthorhombic phase. Additionally, this gradient design accelerates domain switching speed by enhancing the domain wall mobility under applied electric fields. To demonstrate the neuromorphic computing potential, we implemented an artificial neural network using Pt/Zn: HCO/p + -Si synaptic devices, achieving an 86.5 % recognition accuracy in standard pattern classification tasks. This work establishes a viable strategy for simultaneously enhancing both ferroelectric polarization and switching speed in HfO 2 -based memory and neuromorphic devices.
研究领域:
材料科学
·
微电子学
·
纳米科技
·
神经形态工程
·
固态物理
✓ 已验证
产品关联
DOI
高影响因子
Small
·
2021
·Vol. 18
·期 8
·2105599
·
IF 13.281
Wuhong Xue,Qitao Jiang,Fakun Wang,Ri He,Ruixue Pang,Huali Yang,Peng Wang,Ruilong Yang,Zhicheng Zhong,Tianyou Zhai,Xiaohong Xu
2D ferroelectrics with robust polar order in the atomic-scale thickness at room temperature are needed to miniaturize ferroelectric devices and tackle challenges imposed by traditional ferroelectrics. These materials usually have polar point group structure regarding as a prerequisite of ferroelectricity. Yet, to introduce polar structure into otherwise nonpolar 2D materials for producing ferroelectricity remains a challenge. Here, by combining first-principles calculations and experimental studies, it is reported that the native Ga vacancy-defects located in the asymmetrical sites in cubic defective semiconductor α‑Ga 2 Se 3 can induce polar structure. Meanwhile, the induced polarization can be switched in a moderate energy barrier. The switched polarization is observed in 2D α‑Ga 2 Se 3 nanoflakes of ≈4 nm with a high switching temperature up to 450 K. Such polarization switching could arise from the displacement of Ga vacancy between neighboring asymmetrical sites by applying an electric field. This work removes the point group limit for ferroelectricity, expanding the range of 2D ferroelectrics into the native defective semiconductors.
研究领域:
材料科学
·
凝聚态物理
·
纳米电子学
·
功能材料
·
半导体物理
✓ 已验证
DOI
高影响因子
CHINESE JOURNAL OF POLYMER SCIENCE
·
2025
·Vol. 43
·期 4
·588-596
·
IF 4
Yuan Ling-Xin,Liu Chang-Yue,Yang Ji-Ping,Wang Zhi-Jian
Soft robots have shown great advantages with simple structure, high degree of freedom, continuous deformation, and benign human-machine interaction. In the past decades, a variety of soft robots, including crawling, jumping, swimming, and climbing robots, have been developed inspired by living creatures. However, most of the reported bionic soft robots have only a single mode of motion, which limits their practical application. Herein, we report a fully 3D printed crawling and flipping soft robot using liquid metal incorporated liquid crystal elastomer (LM-LCE) composite as the actuator. With the application of voltage, liquid metal works as the conductive Joule heating material to induce the contraction of the LCE layer. The bending angle of the LM-LCE composite actuator highly depends on the applied voltage. We further demonstrate that the soft robot can exhibit distinct moving behaviors, such as crawling or flipping, by applying different voltages. The fully 3D printed LM-LCE composite structure provides a strategy for the fast construction of soft robots with diverse motion modes.
研究领域:
生物医学工程
·
智能材料
·
软体机器人
·
功能高分子材料
·
电热驱动
✓ 已验证
产品关联
DOI
高影响因子
FOOD CHEMISTRY
·
2023
·
IF 8.8
Xinmiao Wang,Qian Wang,Jinghan Yu,Xu Guo,Peiyong Tong,Fawen Yin,Xiaoyang Liu,Dayong Zhou
HPLC-UV analysis in rat everted gut sac and in vitro simulated digestion models indicated that hydroxytyrosol fatty acid esters (HTy-Es) could be hydrolyzed by pancreatic lipase to slow-release of free fatty acids (FAs) and HTy. Meanwhile, the HTy-Es, the liberated FAs and the HTy could cross the membrane and were transported into blood circulation. HTy-Es were further hydrolyzed by carboxylesterase in in vitro rat plasma hydrolysis model, which also showed slow-release of FAs (C1-C4) and HTy. Especially, the rates of hydrolysis and transport initially increased and then decreased with the increasing alkyl chain length. Besides, the above rates of the HTy-Es with a straight chain were greater than those of its isomer with a branched chain. Therefore, the above-mentioned continuous and slow-release of FAs and HTy in small intestine and blood clearly demonstrated that HTy-Es would be an effective approach to enhance oral bioavailabilities of free fatty acids and hydroxytyrosol.
研究领域:
药学
·
营养学
·
生物化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
ACS Nano
·
2025
·
IF 16
Fushou Liu,Tao Tang,Jian Guo,Wendi Xu,Fangtao Tan,Linfeng Wang,Mingxi Zhang,Ran Cui
Inflammatory bowel disease (IBD) is a common chronic gastrointestinal inflammatory disease with an increasing global incidence. However, a significant challenge in IBD management lies in the coordination between high stability and targeting properties of diagnostic and therapeutic agents. Here, we engineer near-infrared-IIb (NIR-IIb) fluorescent nanozymes with pH-responsive surface charge flipping ability for imaging-guided therapy of IBD. The nanozymes exhibit protonation-induced positive charge (+2.6 mV) in gastric acid for enhanced stability, switching to negative charge (−7.2 mV) in intestinal fluid for targeted accumulation. Therefore, these NIR-IIb fluorescent nanozymes could markedly bypass gastric acid barriers and target damaged colon tissue, revealing a significant NIR-IIb signal in early-stage IBD models versus the control. Meanwhile, Mn doping confers a reactive oxygen species scavenging ability, alleviating inflammation in colitis mice. This dual-functional platform overcomes gastrointestinal barriers, enabling precise lesion targeting and therapy monitoring and offering a promising strategy for personalized IBD management.
研究领域:
纳米医学
·
胃肠病学
·
生物医学成像
·
炎症性疾病
·
诊疗一体化
✓ 已验证
产品关联
DOI
PubMed
高影响因子
危险品化学品经营许可证（带存储）