Nano Letters最新文献_第8页

Dissecting the Membrane Association Mechanism of Aerolysin Pores at Femtomolar Concentrations Using Water as a Probe. 以水为探针，剖析费摩尔浓度下气溶胶素孔的膜结合机制

IF 9.6 1区材料科学

Nano Letters Pub Date : 2024-11-06 Epub Date: 2024-10-29 DOI: 10.1021/acs.nanolett.4c00035

Tereza Roesel, Chan Cao, Juan F Bada Juarez, Matteo Dal Peraro, Sylvie Roke

{"title":"Dissecting the Membrane Association Mechanism of Aerolysin Pores at Femtomolar Concentrations Using Water as a Probe.","authors":"Tereza Roesel, Chan Cao, Juan F Bada Juarez, Matteo Dal Peraro, Sylvie Roke","doi":"10.1021/acs.nanolett.4c00035","DOIUrl":"10.1021/acs.nanolett.4c00035","url":null,"abstract":"Aerolysin is a bacterial toxin that forms transmembrane pores at the host plasma membrane and has a narrow internal diameter and great stability. These assets make it a highly promising nanopore for detecting biopolymers such as nucleic acids and peptides. Although much is known about aerolysin from a microbiological and structural perspective, its membrane association and pore-formation mechanism are not yet fully understood. Here, we used angle-resolved second harmonic scattering (AR-SHS) and single-channel current measurements to investigate how wild-type (wt) aerolysin and its mutants interact with liposomes in aqueous solutions at femtomolar concentrations. Our AR-SHS experiments were sensitive enough to detect changes in the electrostatic properties of membrane-bound aerolysin, which were induced by variations in pH levels. We reported for the first time the membrane binding affinity of aerolysin at different stages of the pore formation mechanism: while wt aerolysin has a binding affinity as high as 20 fM, the quasi-pore and the prepore states show gradually decreasing membrane affinities, incomplete insertion, and a pore opening signature. Moreover, we quantitatively characterized the membrane affinity of mutants relevant for applications to nanopore sensing. Our study provides a label-free method for efficiently screening biological pores suitable for conducting molecular sensing and sequencing measurements as well as for probing pore-forming processes.","PeriodicalId":53,"journal":{"name":"Nano Letters","volume":null,"pages":null},"PeriodicalIF":9.6,"publicationDate":"2024-11-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11544699/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142520257","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

An Alternating-Electric-Field-Driven Assembly of DNA Nanoparticles into FCC Crystals. 交变电场驱动 DNA 纳米粒子组装成 FCC 晶体。

IF 9.6 1区材料科学

Nano Letters Pub Date : 2024-11-06 Epub Date: 2024-10-07 DOI: 10.1021/acs.nanolett.4c03167

Jianing Zhang, Dongbao Yao, Wenqiang Hua, Jing Jin, Wei Jiang

引用次数: 0

Bubble-Inspired Multifunctional Magnetic Microrobots for Integrated Multidimensional Targeted Biosensing. 用于集成多维靶向生物传感的气泡启发多功能磁性微型机器人

IF 9.6 1区材料科学

Nano Letters Pub Date : 2024-11-06 Epub Date: 2024-10-03 DOI: 10.1021/acs.nanolett.4c03089

Zichen Xu, Heng Sun, Yuanhe Chen, Hon Ho Yu, Chu-Xia Deng, Qingsong Xu

{"title":"Bubble-Inspired Multifunctional Magnetic Microrobots for Integrated Multidimensional Targeted Biosensing.","authors":"Zichen Xu, Heng Sun, Yuanhe Chen, Hon Ho Yu, Chu-Xia Deng, Qingsong Xu","doi":"10.1021/acs.nanolett.4c03089","DOIUrl":"10.1021/acs.nanolett.4c03089","url":null,"abstract":"Microrobots possessing multifunctional integration are desired for therapeutics and biomedicine applications. However, existing microrobots with desired functionalities need to be fabricated through complex procedures due to their constrained volume, limited manufacturing processes, and lack of effective in vivo observation methods. Inspired by bubbles exhibiting various abilities, we report magnetic air bubble microrobots with simpler structures to simultaneously integrate multiple functions, including microcargo delivery, multimode locomotion, imaging, and biosensing. Contributed by buoyancy and magnetic actuation to overcome obstacles, flexible three-dimensional locomotion is implemented, guaranteeing the integrity of micro-objects adsorbed on the surface of the air bubble microrobot. Introducing air microbubbles enhances the ultrasound imaging capability of microrobots in the vascular system of mice in vivo, facilitating ample medical applications. Moreover, air-liquid reactions endow microrobots with rapid pH biosensing. This work provides a unique strategy to utilize relatively simple air bubbles to achieve the complex functions of microrobots for biomedical applications.","PeriodicalId":53,"journal":{"name":"Nano Letters","volume":null,"pages":null},"PeriodicalIF":9.6,"publicationDate":"2024-11-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11544691/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142363481","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

An Aged Tree with a New Bloom: A Simple Spatiotemporal Programming Strategy Enables Carbon Dot Photosensitizers to Regulate Cell Pyroptosis for Enhanced Tumor Photodynamic-Immunotherapy 老树开新花：一种简单的时空编程策略可使碳点光敏剂调节细胞跃迁，从而增强肿瘤光动力免疫疗法的效果

IF 10.8 1区材料科学

Nano Letters Pub Date : 2024-11-06 DOI: 10.1021/acs.nanolett.4c03913

Tiejin Chen, Ke Liang, Jian Wang, Jian Li, Xiaokuang Xue, Yongliang Hao, Huanyi Liang, Haohui Ren, Haihua Xiao, Jiechao Ge, Bo Tang

{"title":"An Aged Tree with a New Bloom: A Simple Spatiotemporal Programming Strategy Enables Carbon Dot Photosensitizers to Regulate Cell Pyroptosis for Enhanced Tumor Photodynamic-Immunotherapy","authors":"Tiejin Chen, Ke Liang, Jian Wang, Jian Li, Xiaokuang Xue, Yongliang Hao, Huanyi Liang, Haohui Ren, Haihua Xiao, Jiechao Ge, Bo Tang","doi":"10.1021/acs.nanolett.4c03913","DOIUrl":"https://doi.org/10.1021/acs.nanolett.4c03913","url":null,"abstract":"Pyroptosis induced by photodynamic therapy (PDT) is a promising field in both PDT and immunotherapy for tumors. However, effectively inducing tumor cell pyroptosis while triggering a strong immune response using current photosensitizers remains challenging. Herein, the developed positively charged carbon dots (PCDs) nanoPSs were utilized to modulate tumor cell pyroptosis for the first time through a simple spatiotemporal programming strategy. Briefly, PCDs enabled precisely time-dependent targeting of the cell membrane or lysosome. Upon light irradiation, in vitro studies revealed that lysosome-targeted PDT primarily induced apoptosis, while membrane-targeted PDT triggered pyroptosis, resulting in enhanced PDT efficacy and robust activation of the immune response. Conclusively, in vivo studies demonstrated that PCDs could serve as a novel pyroptosis nanotuner for enhanced photodynamic-immunotherapy, thereby simultaneously eliminating primary tumors and inhibiting distant tumor growth and metastases. This spatiotemporal programming strategy unprecedentedly offers a rejuvenation of aged PSs and expands the biomedical use of CDs in immunotherapy.","PeriodicalId":53,"journal":{"name":"Nano Letters","volume":null,"pages":null},"PeriodicalIF":10.8,"publicationDate":"2024-11-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142588950","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Probing Single-Molecule Dynamics in Self-Assembling Viral Nucleocapsids 自组装病毒核苷酸中的单分子动力学探测

IF 10.8 1区材料科学

Nano Letters Pub Date : 2024-11-06 DOI: 10.1021/acs.nanolett.4c04458

Thomas Bugea, Roméo Suss, Laetitia Gargowitsch, Charles Truong, Karen Perronet, Guillaume Tresset

{"title":"Probing Single-Molecule Dynamics in Self-Assembling Viral Nucleocapsids","authors":"Thomas Bugea, Roméo Suss, Laetitia Gargowitsch, Charles Truong, Karen Perronet, Guillaume Tresset","doi":"10.1021/acs.nanolett.4c04458","DOIUrl":"https://doi.org/10.1021/acs.nanolett.4c04458","url":null,"abstract":"All viruses on Earth rely on host cell machinery for replication, a process that involves a complex self-assembly mechanism. Our aim here is to scrutinize in real time the growth of icosahedral viral nucleocapsids with single-molecule precision. Using total internal reflection fluorescence microscopy, we probed the binding and unbinding dynamics of fluorescently labeled capsid subunits on hundreds of immobilized viral RNA molecules simultaneously at each time point. A step-detection algorithm combined with statistical analysis allowed us to estimate microscopic quantities such as the equilibrium binding rate and mean residence time, which are otherwise inaccessible through traditional ensemble-averaging techniques. Additionally, we could estimate a set of rate constants modeling the growth kinetics from nonequilibrium measurements, and we observed an acceleration in growth caused by the electrostatic screening effect of monovalent salts. Single-molecule fluorescence imaging will be crucial for elucidating virus self-assembly at the molecular level, particularly in crowded, cell-like environments.","PeriodicalId":53,"journal":{"name":"Nano Letters","volume":null,"pages":null},"PeriodicalIF":10.8,"publicationDate":"2024-11-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142589053","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Highly Charged Cellulose Nanocrystals via Electrochemical Oxidation 通过电化学氧化实现高电荷纤维素纳米晶体

IF 10.8 1区材料科学

Nano Letters Pub Date : 2024-11-06 DOI: 10.1021/acs.nanolett.4c02918

Neptun Yousefi, Jenna Hannonen, Lukas Fliri, Pekka Peljo, Eero Kontturi

引用次数: 0

Intraband Exciton Dynamics of n-Doped Silver Selenide Quantum Dots. 正掺杂硒化银量子点的带内激子动力学。

IF 9.6 1区材料科学

Nano Letters Pub Date : 2024-11-06 Epub Date: 2024-10-28 DOI: 10.1021/acs.nanolett.4c02659

Rajesh Bera, Miguel Dosil, Gerasimos Konstantatos

{"title":"Intraband Exciton Dynamics of n-Doped Silver Selenide Quantum Dots.","authors":"Rajesh Bera, Miguel Dosil, Gerasimos Konstantatos","doi":"10.1021/acs.nanolett.4c02659","DOIUrl":"10.1021/acs.nanolett.4c02659","url":null,"abstract":"AgxSe (x > 2) colloidal quantum dots (CQDs) have recently emerged as a promising environmentally friendly material contender for mid- and long-wave infrared optoelectronics, leveraging their intraband transition (1Se-1Pe). However, multicarrier interactions in CQDs, particularly Auger recombination, have profound implications on the optoelectronic properties of the materials and their potential in device applications. Understanding the intraband excited-state dynamics in n-doped AgxSe is therefore essential for the assessment and successful implementation of this material platform in devices. We, herein, investigate the carrier dynamics of AgxSe in both solution and thin-film states using a femtosecond mid-infrared transient absorption spectrometer. Our observations reveal that the multicarrier Auger process depends on the degree of doping in AgxSe CQDs and accelerates when the Fermi energy (EF) level approaches the 1Pe state. The calculated intraband Auger coefficients (CA) are measured to be on the order of ∼10-28 cm6 s-1, significantly larger compared to analogous n-doped HgS/Se CQDs.","PeriodicalId":53,"journal":{"name":"Nano Letters","volume":null,"pages":null},"PeriodicalIF":9.6,"publicationDate":"2024-11-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11544693/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142491116","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Phonon Transport in Supramolecular Polymers Regulated by Hydrogen Bonds. 受氢键调节的超分子聚合物中的声子传输。

IF 9.6 1区材料科学

Nano Letters Pub Date : 2024-11-06 Epub Date: 2024-10-07 DOI: 10.1021/acs.nanolett.4c04306

Ting Meng, Peng Zhang, Hongmei Zhong, Hongda Zhu, Hui Zhang, Dongyan Xu, Yang Zhao

{"title":"Phonon Transport in Supramolecular Polymers Regulated by Hydrogen Bonds.","authors":"Ting Meng, Peng Zhang, Hongmei Zhong, Hongda Zhu, Hui Zhang, Dongyan Xu, Yang Zhao","doi":"10.1021/acs.nanolett.4c04306","DOIUrl":"10.1021/acs.nanolett.4c04306","url":null,"abstract":"Supramolecular polymers hold promise in thermal management applications due to their multistability, high responsiveness, and cost-effectiveness. In this work, we successfully regulate phonon transport at the molecular level in supramolecular polymers by adjusting the strength of intermolecular hydrogen bonding. We synthesized three supramolecular polymer fibers with thermal conductivity differences of up to 289% based on melamine (M) and three simple positional isomers of hydroxybenzoic acid. Differential Scanning Calorimetry (DSC) measurement revealed discrepancies in thermal stability of the polymers, where structures with higher stability exhibited enhanced thermal conductivity. Fourier Transform Infrared Spectroscopy (FTIR) measurement and Density Functional Theory (DFT) calculations indicate that these differences arise from variations in hydrogen-bonding strengths at different bonding sites. Higher hydrogen-bonding strength leads to more stable thermal pathways, reduces phonon scattering, and increases thermal conductivity. Our findings provide valuable insights into controlling the thermal conductivity of polymer fibers, paving the way for applications in phonon-based thermal devices.","PeriodicalId":53,"journal":{"name":"Nano Letters","volume":null,"pages":null},"PeriodicalIF":9.6,"publicationDate":"2024-11-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142379478","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Thermal Characterization of Ultrathin MgO Tunnel Barriers. 超薄氧化镁隧道势垒的热特性分析。

IF 9.6 1区材料科学

Nano Letters Pub Date : 2024-11-06 DOI: 10.1021/acs.nanolett.4c02571

Haotian Su, Heungdong Kwon, Fen Xue, Noriyuki Sato, Usha Bhat, Wilman Tsai, Michel Bosman, Mehdi Asheghi, Kenneth E Goodson, Eric Pop, Shan X Wang

{"title":"Thermal Characterization of Ultrathin MgO Tunnel Barriers.","authors":"Haotian Su, Heungdong Kwon, Fen Xue, Noriyuki Sato, Usha Bhat, Wilman Tsai, Michel Bosman, Mehdi Asheghi, Kenneth E Goodson, Eric Pop, Shan X Wang","doi":"10.1021/acs.nanolett.4c02571","DOIUrl":"https://doi.org/10.1021/acs.nanolett.4c02571","url":null,"abstract":"Magnetic tunnel junctions (MTJs) with ultrathin MgO tunnel barriers are at the heart of magnetic random-access memory (MRAM) and exhibit potential for spin caloritronics applications due to the tunnel magneto-Seebeck effect. However, the high programming current in MRAM can cause substantial heating which degrades the endurance and reliability of MTJs. Here, we report the thermal characterization of ultrathin CoFeB/MgO multilayers with total thicknesses of 4.4, 8.8, 22, and 44 nm, and with varying MgO thicknesses (1.0, 1.3, and 1.6 nm). Through time-domain thermoreflectance (TDTR) measurements and thermal modeling, we extract the intrinsic (∼3.6 W m-1 K-1) and effective (∼0.85 W m-1 K-1) thermal conductivities of annealed 1.0 nm thick MgO at room temperature. Our study reveals the thermal properties of ultrathin MgO tunnel barriers, especially the role of thermal boundary resistance, and contributes to a more precise thermal analysis of MTJs to improve the design and reliability of MRAM technologies.","PeriodicalId":53,"journal":{"name":"Nano Letters","volume":null,"pages":null},"PeriodicalIF":9.6,"publicationDate":"2024-11-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142580904","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Dielectric Metasurfaces for Broadband Phase-Contrast Relief-Like Imaging 用于宽带相位对比浮雕成像的介质元表面

IF 10.8 1区材料科学

Nano Letters Pub Date : 2024-11-06 DOI: 10.1021/acs.nanolett.4c03695

Ming Deng, Saima Kanwal, Zhuochao Wang, Chengkun Cai, Yongzhi Cheng, Jianguo Guan, Guangwei Hu, Jian Wang, Jing Wen, Lin Chen

{"title":"Dielectric Metasurfaces for Broadband Phase-Contrast Relief-Like Imaging","authors":"Ming Deng, Saima Kanwal, Zhuochao Wang, Chengkun Cai, Yongzhi Cheng, Jianguo Guan, Guangwei Hu, Jian Wang, Jing Wen, Lin Chen","doi":"10.1021/acs.nanolett.4c03695","DOIUrl":"https://doi.org/10.1021/acs.nanolett.4c03695","url":null,"abstract":"The visualization of transparent specimens in traditional light microscopy is impeded by insufficient intrinsic contrast, prompting the development of advanced contrast-enhancement methodologies to transmute minute phase discrepancies into detectable amplitude alterations. While existing methods excel in either phase-contrast imaging (contrast-enhanced image of whole objects) or relief-like imaging (deceptive three-dimensional images), it would be of great significance to seamlessly integrate both capabilities in the same device. Here, we propose a novel metasurface-assisted half-side phase-contrast technique capable of simultaneous phase-contrast and relief-like imaging across the visible spectrum, which is realized by introducing a ±π/2 phase shift to a half-side diffracted wave emitted by the objects. Our method showcases successful application to diverse specimens, including a transparent silica disk and a frog egg cell. Our work substantiates high-quality microscopic imaging of various transparent specimens, which has profound implications in cellular biology, materials science, and medical diagnostics.","PeriodicalId":53,"journal":{"name":"Nano Letters","volume":null,"pages":null},"PeriodicalIF":10.8,"publicationDate":"2024-11-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142589209","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0