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Schlichter L, Jersch J, Demokritov SO, Ravoo BJ. Multi-Stimuli-Responsive Water-Dispersible Magnetite Nanoparticles Using Arylazopyrazole-Modified Polymer Ligands. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2024; 40:13669-13675. [PMID: 38875303 DOI: 10.1021/acs.langmuir.4c01342] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/16/2024]
Abstract
In order to design new nanomaterials with improved functionalities, magnetite nanoparticles (MNP) modified with arylazopyrazole (AAP) molecular photoswitches are presented. Water dispersibility is achieved by using poly(acrylic acid) (pAA) as a multidentate ligand, which is modified with AAP by amide coupling. The polymer ligand stabilizes the MNP, allows for E-Z isomerization of the photoswitch, and provides pH responsiveness. Three different AAP are synthesized and attached to pAA via amide coupling giving pAA-AAP with photoswitches substituted statistically along the hydrophilic polymer backbone. MNP are synthesized by coprecipitation and pAA-AAP is introduced as a stabilizing agent in situ. Photoisomerization of pAA-AAP and pAA-AAP@MNP is investigated showing good photostationary states and cyclability. The MNP can be assembled and dispersed reversibly in water either by applying a magnetic field or by a change in pH.
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Affiliation(s)
- Lisa Schlichter
- Center for Soft Nanoscience and Organic Chemistry Institute, University of Münster, Busso-Peus-Straße 10, 48149 Münster, Germany
| | - Johann Jersch
- Institute of Applied Physics, University of Münster, Corrensstraße 2, 48149 Münster, Germany
| | - Sergej O Demokritov
- Institute of Applied Physics, University of Münster, Corrensstraße 2, 48149 Münster, Germany
| | - Bart Jan Ravoo
- Center for Soft Nanoscience and Organic Chemistry Institute, University of Münster, Busso-Peus-Straße 10, 48149 Münster, Germany
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2
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Sarabamoun ES, Bietsch JM, Aryal P, Reid AG, Curran M, Johnson G, Tsai EHR, Machan CW, Wang G, Choi JJ. Photoluminescence switching in quantum dots connected with fluorinated and hydrogenated photochromic molecules. RSC Adv 2024; 14:424-432. [PMID: 38173584 PMCID: PMC10759204 DOI: 10.1039/d3ra07539g] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2023] [Accepted: 12/14/2023] [Indexed: 01/05/2024] Open
Abstract
We investigate switching of photoluminescence (PL) from PbS quantum dots (QDs) crosslinked with two different types of photochromic diarylethene molecules, 4,4'-(1-cyclopentene-1,2-diyl)bis[5-methyl-2-thiophenecarboxylic acid] (1H) and 4,4'-(1-perfluorocyclopentene-1,2-diyl)bis[5-methyl-2-thiophenecarboxylic acid] (2F). Our results show that the QDs crosslinked with the hydrogenated molecule (1H) exhibit a greater amount of switching in photoluminescence intensity compared to QDs crosslinked with the fluorinated molecule (2F). With a combination of differential pulse voltammetry and density functional theory, we attribute the different amount of PL switching to the different energy levels between 1H and 2F molecules which result in different potential barrier heights across adjacent QDs. Our findings provide a deeper understanding of how the energy levels of bridge molecules influence charge tunneling and PL switching performance in QD systems and offer deeper insights for the future design and development of QD based photo-switches.
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Affiliation(s)
| | - Jonathan M Bietsch
- Department of Chemistry and Biochemistry, Old Dominion University Norfolk VA 23529 USA
| | - Pramod Aryal
- Department of Chemistry and Biochemistry, Old Dominion University Norfolk VA 23529 USA
| | - Amelia G Reid
- Department of Chemistry, University of Virginia PO Box 400319 Charlottesville VA 22904 USA
| | - Maurice Curran
- Department of Chemical Engineering, University of Virginia Charlottesville VA 22904 USA
| | - Grayson Johnson
- Department of Chemical Engineering, University of Virginia Charlottesville VA 22904 USA
| | - Esther H R Tsai
- Center for Functional Nanomaterials, Brookhaven National Laboratory Upton NY 11973 USA
| | - Charles W Machan
- Department of Chemistry, University of Virginia PO Box 400319 Charlottesville VA 22904 USA
| | - Guijun Wang
- Department of Chemistry and Biochemistry, Old Dominion University Norfolk VA 23529 USA
| | - Joshua J Choi
- Department of Chemical Engineering, University of Virginia Charlottesville VA 22904 USA
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Li J, Jia X. Photo-Controlled Self-Assembly of Nanoparticles: A Promising Strategy for Development of Novel Structures. NANOMATERIALS (BASEL, SWITZERLAND) 2023; 13:2562. [PMID: 37764591 PMCID: PMC10535597 DOI: 10.3390/nano13182562] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/17/2023] [Revised: 09/10/2023] [Accepted: 09/11/2023] [Indexed: 09/29/2023]
Abstract
Photo-controlled self-assembly of nanoparticles (NPs) is an advanced and promising approach to address a series of material issues from the molecular level to the nano/micro scale, owing to the fact that light stimulus is typically precise and rapid, and can provide contactless spatial and temporal control. The traditional photo-controlled assembly of NPs is based on photochemical processes through NPs modified by photo-responsive molecules, which are realized through the change in chemical structure under irradiation. Moreover, photoexcitation-induced assembly of NPs is another promising physical strategy, and such a strategy aims to employ molecular conformational change in the excited state (rather than the chemical structure) to drive molecular motion and assembly. The exploration and control of NP assembly through such a photo-controlled strategy can open a new paradigm for scientists to deal with "bottom-up" behaviors and develop unprecedented optoelectronic functional materials.
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Affiliation(s)
| | - Xiaoyong Jia
- Henan Key Laboratory of Photovoltaic Materials, College of Future Technical, Henan University, Kaifeng 475004, China;
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Facile synthesis of magnetic photo-responsive nanoparticles based on 1,3-diazabicyclo[3.1.0]hex-3-en: An enhanced adsorption of toxic dyes from aqueous solution under sunlight. J Mol Struct 2022. [DOI: 10.1016/j.molstruc.2022.133130] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
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Rival JV, Mymoona P, Lakshmi KM, Pradeep T, Shibu ES. Self-Assembly of Precision Noble Metal Nanoclusters: Hierarchical Structural Complexity, Colloidal Superstructures, and Applications. SMALL (WEINHEIM AN DER BERGSTRASSE, GERMANY) 2021; 17:e2005718. [PMID: 33491918 DOI: 10.1002/smll.202005718] [Citation(s) in RCA: 52] [Impact Index Per Article: 17.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/14/2020] [Revised: 11/07/2020] [Indexed: 06/12/2023]
Abstract
Ligand protected noble metal nanoparticles are excellent building blocks for colloidal self-assembly. Metal nanoparticle self-assembly offers routes for a wide range of multifunctional nanomaterials with enhanced optoelectronic properties. The emergence of atomically precise monolayer thiol-protected noble metal nanoclusters has overcome numerous challenges such as uncontrolled aggregation, polydispersity, and directionalities faced in plasmonic nanoparticle self-assemblies. Because of their well-defined molecular compositions, enhanced stability, and diverse surface functionalities, nanoclusters offer an excellent platform for developing colloidal superstructures via the self-assembly driven by surface ligands and metal cores. More importantly, recent reports have also revealed the hierarchical structural complexity of several nanoclusters. In this review, the formulation and periodic self-assembly of different noble metal nanoclusters are focused upon. Further, self-assembly induced amplification of physicochemical properties, and their potential applications in molecular recognition, sensing, gas storage, device fabrication, bioimaging, therapeutics, and catalysis are discussed. The topics covered in this review are extensively associated with state-of-the-art achievements in the field of precision noble metal nanoclusters.
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Affiliation(s)
- Jose V Rival
- Smart Materials Lab, Electrochemical Power Sources (ECPS) Division, Council of Scientific and Industrial Research (CSIR)-Central Electrochemical Research Institute (CECRI), Karaikudi, Tamil Nadu, 630003, India
- Academy of Scientific and Innovative Research (AcSIR)-CSIR, Ghaziabad, Uttar Pradesh, 201002, India
| | - Paloli Mymoona
- Smart Materials Lab, Electrochemical Power Sources (ECPS) Division, Council of Scientific and Industrial Research (CSIR)-Central Electrochemical Research Institute (CECRI), Karaikudi, Tamil Nadu, 630003, India
- Academy of Scientific and Innovative Research (AcSIR)-CSIR, Ghaziabad, Uttar Pradesh, 201002, India
| | - Kavalloor Murali Lakshmi
- Smart Materials Lab, Electrochemical Power Sources (ECPS) Division, Council of Scientific and Industrial Research (CSIR)-Central Electrochemical Research Institute (CECRI), Karaikudi, Tamil Nadu, 630003, India
- Academy of Scientific and Innovative Research (AcSIR)-CSIR, Ghaziabad, Uttar Pradesh, 201002, India
| | - Thalappil Pradeep
- Department of Chemistry, DST Unit of Nanoscience (DST UNS) and Thematic Unit of Excellence (TUE), Indian Institute of Technology (IIT) Madras, Chennai, Tamil Nadu, 600036, India
| | - Edakkattuparambil Sidharth Shibu
- Smart Materials Lab, Electrochemical Power Sources (ECPS) Division, Council of Scientific and Industrial Research (CSIR)-Central Electrochemical Research Institute (CECRI), Karaikudi, Tamil Nadu, 630003, India
- Academy of Scientific and Innovative Research (AcSIR)-CSIR, Ghaziabad, Uttar Pradesh, 201002, India
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Dynamic emulsion droplets enabled by interfacial assembly of azobenzene-functionalized nanoparticles under light and magnetic field. J Colloid Interface Sci 2021; 583:586-593. [PMID: 33038608 DOI: 10.1016/j.jcis.2020.09.058] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2020] [Revised: 09/15/2020] [Accepted: 09/16/2020] [Indexed: 11/22/2022]
Abstract
HYPOTHESIS The ability to control the assembly of micro/nanosized particles at liquid-liquid interface with external inputs promises new opportunities in nanofabrication and biomedicines. This work aims to demonstrate a way to control of dynamic assembly of nanoparticles at liquid-liquid interface by light and magnetic field, which consequently enables the formation of dynamic emulsion droplets. EXPERIMENTS Magnetic Fe3O4 nanoparticles functionalized with azobenzene moieties (Fe3O4@AZO) were synthesized and were dispersed in toluene/(N,N-dimethylformamide, DMF) binary solvent. After irradiation with UV or visible light, the assembly behavior of these Fe3O4 nanoparticles were evaluated by electron microscopy and fluorescent microscopy. FINDINGS Under UV light, Fe3O4@AZO nanoparticles were self-assembled due to the increase of dipolar interaction from the photoisomerization of azobenzene and polar molecules, DMF, were harvested from a binary solvent of DMF/toluene. While under visible light, a relief of dipolar interactions between Fe3O4@AZO nanoparticles can induce the secondary assembly of these Fe3O4@AZO nanoparticles at DMF-toluene interface, resulting in DMF droplets covered by a layer of nanoparticle superlattices. More importantly, coupled with a magnetic field, these emulsion droplets can be shaped into one dimensional ones during the interfacial assembly process, thereby giving rise to dynamic emulsions controlled by light and magnetic field.
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Sreekanth T, Nam ND, Kim J, Yoo K. SnO2 QDs@CoFe2O4 NPs as an efficient electrocatalyst for methanol oxidation and oxygen evolution reactions in alkaline media. J Electroanal Chem (Lausanne) 2020. [DOI: 10.1016/j.jelechem.2020.114363] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
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8
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Chu Z, Klajn R. Polysilsesquioxane Nanowire Networks as an "Artificial Solvent" for Reversible Operation of Photochromic Molecules. NANO LETTERS 2019; 19:7106-7111. [PMID: 31539469 DOI: 10.1021/acs.nanolett.9b02642] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
Efficient isomerization of photochromic molecules often requires conformational freedom and is typically not available under solvent-free conditions. Here, we report a general methodology allowing for reversible switching of such molecules on the surfaces of solid materials. Our method is based on dispersing photochromic compounds within polysilsesquioxane nanowire networks (PNNs), which can be fabricated as transparent, highly porous, micrometer-thick layers on various substrates. We found that azobenzene switching within the PNNs proceeded unusually fast compared with the same molecules in liquid solvents. Efficient isomerization of another photochromic system, spiropyran, from a colorless to a colored form was used to create reversible images in PNN-coated glass. The coloration reaction could be induced with sunlight and is of interest for developing "smart" windows.
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Affiliation(s)
- Zonglin Chu
- Department of Organic Chemistry , Weizmann Institute of Science , Rehovot 76100 , Israel
| | - Rafal Klajn
- Department of Organic Chemistry , Weizmann Institute of Science , Rehovot 76100 , Israel
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Hyaluronic acid tethered pH-responsive alloy-drug nanoconjugates for multimodal therapy of glioblastoma: An intranasal route approach. MATERIALS SCIENCE & ENGINEERING. C, MATERIALS FOR BIOLOGICAL APPLICATIONS 2019; 98:419-436. [DOI: 10.1016/j.msec.2018.12.139] [Citation(s) in RCA: 33] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/22/2018] [Revised: 12/23/2018] [Accepted: 12/31/2018] [Indexed: 01/03/2023]
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10
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Moniruzzaman M, Christogianni P, Vrcelj RM, Gill PP. Ultrasonic Studies of Solid Azobenzene-Decorated Polymer Thin Films. ACS OMEGA 2018; 3:17693-17699. [PMID: 31458368 PMCID: PMC6644014 DOI: 10.1021/acsomega.8b02048] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/15/2018] [Accepted: 11/20/2018] [Indexed: 06/10/2023]
Abstract
This work investigates the effect of ultrasound on switching of cis azobenzene isomers to their trans counterparts in solid films of methyl methacrylate and methacryloyloxyazobenzene copolymers [P(MMA/MOAB)]. Ultraviolet-visible and 1H nuclear magnetic resonance spectroscopies demonstrate that 46% of the cis isomer converts to the trans form purely by ultrasonic agitation and 46% converts to the trans isomer by localized ultrasound-induced heating effects. Comparative studies of isomerization by ultrasound wave, heat, and visible irradiation show that ultrasound exposure requires a longer time to switch the cis-to-trans conformation. The estimated activation energy for the cis-to-trans conversion in solid polymer films is shown to be comparable to previous values of azobenzene isomerization, indicating that incorporation of the chromophore in a polymeric system affects the kinetics of transition but not the barriers to conformational change.
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Affiliation(s)
- Mohammed Moniruzzaman
- Centre for Defence Chemistry, Cranfield University, Defence Academy of the United
Kingdom, Shrivenham SN6 8LA, U.K.
| | - Paraskevi Christogianni
- Centre for Defence Chemistry, Cranfield University, Defence Academy of the United
Kingdom, Shrivenham SN6 8LA, U.K.
| | - Ranko M. Vrcelj
- Centre for Defence Chemistry, Cranfield University, Defence Academy of the United
Kingdom, Shrivenham SN6 8LA, U.K.
| | - Philip P. Gill
- Centre for Defence Chemistry, Cranfield University, Defence Academy of the United
Kingdom, Shrivenham SN6 8LA, U.K.
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11
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Wang L, Li Q. Photochromism into nanosystems: towards lighting up the future nanoworld. Chem Soc Rev 2018; 47:1044-1097. [PMID: 29251304 DOI: 10.1039/c7cs00630f] [Citation(s) in RCA: 312] [Impact Index Per Article: 52.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
The ability to manipulate the structure and function of promising nanosystems via energy input and external stimuli is emerging as an attractive paradigm for developing reconfigurable and programmable nanomaterials and multifunctional devices. Light stimulus manifestly represents a preferred external physical and chemical tool for in situ remote command of the functional attributes of nanomaterials and nanosystems due to its unique advantages of high spatial and temporal resolution and digital controllability. Photochromic moieties are known to undergo reversible photochemical transformations between different states with distinct properties, which have been extensively introduced into various functional nanosystems such as nanomachines, nanoparticles, nanoelectronics, supramolecular nanoassemblies, and biological nanosystems. The integration of photochromism into these nanosystems has endowed the resultant nanostructures or advanced materials with intriguing photoresponsive behaviors and more sophisticated functions. In this Review, we provide an account of the recent advancements in reversible photocontrol of the structures and functions of photochromic nanosystems and their applications. The important design concepts of such truly advanced materials are discussed, their fabrication methods are emphasized, and their applications are highlighted. The Review is concluded by briefly outlining the challenges that need to be addressed and the opportunities that can be tapped into. We hope that the review of the flourishing and vibrant topic with myriad possibilities would shine light on exploring the future nanoworld by encouraging and opening the windows to meaningful multidisciplinary cooperation of engineers from different backgrounds and scientists from the fields such as chemistry, physics, engineering, biology, nanotechnology and materials science.
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Affiliation(s)
- Ling Wang
- Liquid Crystal Institute and Chemical Physics Interdisciplinary Program, Kent State University, Kent, Ohio 44242, USA.
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12
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Suda M. A New Photo-Control Method for Organic–Inorganic Interface Dipoles and Its Application to Photo-Controllable Molecular Devices. BULLETIN OF THE CHEMICAL SOCIETY OF JAPAN 2018. [DOI: 10.1246/bcsj.20170283] [Citation(s) in RCA: 30] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Affiliation(s)
- Masayuki Suda
- Institute for Molecular Science, 38, Nishigo-naka, Myodaiji, Okazaki, Aichi 444-8585
- RIKEN, 2-1, Hirosawa, Wako, Saitama 351-0198
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Liu C, Zheng D, Hu W, Zhu Q, Tian Z, Zhao J, Zhu Y, Ma J. Tuning the collective switching behavior of azobenzene/Au hybrid materials: flexible versus rigid azobenzene backbones and Au(111) surfaces versus curved Au nanoparticles. NANOSCALE 2017; 9:16700-16710. [PMID: 29067386 DOI: 10.1039/c7nr03421k] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
The combination of photo-responsive azobenzene (AB) and biocompatible Au nanomaterials possesses potential applications in diverse fields such as biosensing and thermotherapy. To explore the influence of azobenzene moieties and Au substrates on the collective switching behavior, two different azobenzene derivatives (rigid biphenyl-controlled versus flexible alkoxyl chain-linked) and three different Au substrates (a planar Au(111) surface, curved Au102(SR)44 and Au25(SR)18 clusters) were chosen to form six Au@AB combinations. A reactive molecular dynamics (RMD) model considering both the torsion and inversion path was implemented to simulate the collective photo-induced cis-to-trans switching process of AB monolayers on Au substrates. The major driving force for isomerization is demonstrated to be the torsion of the C-N[double bond, length as m-dash]N-C dihedral angle, in addition to the minor contribution from an inversion pathway. The isomerization process can be divided into the preliminary conformation switching stage and the later relaxation stage, in which a gradual self-organization is observed for 40 ps. The Au substrate affects the packing structure of the AB monolayer, while the choice of different kinds of ABs tunes the intermolecular interaction in the monolayer. Flexible alkoxyl-linked F-AB may achieve much faster conversion on Au clusters than on the surface. For rigid biphenyl-based R-AB anchored on Au nanoparticles (AuNPs), a competitive torsion between the biphenyl and C-N[double bond, length as m-dash]N-C dihedral may delay the C-N[double bond, length as m-dash]N-C dihedral torsion and the following isomerization process. After the R-AB molecules were anchored on the Au(111) surface, the strong π-π stacking between biphenyl units accelerates the collective isomerization process. A curvature-dependent effect is observed for R-AB SAMs on different-sized substrates. The cooperation between functional AB monolayers and the Au substrate determines the collective switching behavior of Au@AB materials. These results are expected to guide rational designs of Au@AB hybrid materials for different uses.
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Affiliation(s)
- Chunyan Liu
- Key Laboratory of Mesoscopic Chemistry of MOE, School of Chemistry & Chemical Engineering, Nanjing University, 22 Hankou Road, Nanjing, 210093, People's Republic of China.
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Natsui K, Yamamoto T, Akahori M, Einaga Y. Photochromism-induced amplification of critical current density in superconducting boron-doped diamond with an azobenzene molecular layer. ACS APPLIED MATERIALS & INTERFACES 2015; 7:887-894. [PMID: 25494096 DOI: 10.1021/am5074613] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
A key issue in molecular electronics is the control of electronic states by optical stimuli, which enables fast and high-density data storage and temporal-spatial control over molecular processes. In this article, we report preparation of a photoswitchable superconductor using a heavily boron-doped diamond (BDD) with a photochromic azobenzene (AZ) molecular layer. BDDs electrode properties allow for electrochemical immobilization, followed by copper(I)-catalyzed alkyne-azide cycloaddition (a "click" reaction). Superconducting properties were examined with magnetic and electrical transport measurements, such as field-dependent isothermal magnetization, temperature-dependent resistance, and the low-temperature voltage-current response. These measurements revealed reversible amplification of the critical current density by 55% upon photoisomerization. This effect is explained as the reversible photoisomerization of AZ inducing an inhomogeneous electron distribution along the BDD surface that renormalizes the surface pinning contribution to the critical current.
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Affiliation(s)
- Keisuke Natsui
- Department of Chemistry, Keio University , 3-14-1 Hiyoshi, Yokohama 223-8522, Japan
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15
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Bastakoti BP, Sukegawa H, Wu KCW, Yamauchi Y. Synthesis of porous iron oxide microspheres by a double hydrophilic block copolymer. RSC Adv 2014. [DOI: 10.1039/c3ra47490a] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023] Open
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Nazarova D, Nedelchev L, Sharlandjiev P, Dragostinova V. Anisotropic hybrid organic/inorganic (azopolymer/SiO2 NP) materials with enhanced photoinduced birefringence. APPLIED OPTICS 2013; 52:E28-E33. [PMID: 23913084 DOI: 10.1364/ao.52.000e28] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/17/2012] [Accepted: 04/09/2013] [Indexed: 06/02/2023]
Abstract
Hybrid materials based on combination of polymers and inorganic nanoparticles (NP) attracted considerable attention in the last decade due to their advantageous electrical, optical, or mechanical properties. Recently, we reported a significant improvement of the photoresponse by doping azopolymers with ZnO NP. To study the influence of the composition of the dopant, in our present work we have synthesized anisotropic organic/inorganic nanocomposite materials by incorporating 5-15 nm sized SiO2 NP in a side-chain azopolymer. As a result we observe an enhancement of the photoinduced birefringence in these composite materials with about 20% compared to the nondoped sample. Additionally, we discuss possible mechanisms leading to this enhancement related with the scattering caused by the NP and the increased mobility of the azochromophores in the vicinity of NP.
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Affiliation(s)
- Dimana Nazarova
- Institute of Optical Materials and Technologies, Bulgarian Academy of Sciences, Sofia, Bulgaria
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Das S, Ranjan P, Maiti PS, Singh G, Leitus G, Klajn R. Dual-responsive nanoparticles and their self-assembly. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2013; 25:422-426. [PMID: 22933327 DOI: 10.1002/adma.201201734] [Citation(s) in RCA: 76] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/29/2012] [Revised: 08/08/2012] [Indexed: 06/01/2023]
Abstract
Dual-responsive nanoparticles are designed by functionalizing magnetic cores with light-responsive ligands. These materials respond to both light and magnetic fields and can be assembled into various higher-order structures, depending on the relative contributions of these two stimuli.
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Affiliation(s)
- Sanjib Das
- Department of Organic Chemistry, Weizmann Institute of Science, Rehovot 76100, Israel
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Yamamoto T, Umemura Y, Einaga Y. Structure-distortion-induced photomagnetic effect in azobenzene/polyoxometalate Langmuir–Blodgett films. Dalton Trans 2013; 42:16014-20. [DOI: 10.1039/c3dt51402a] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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20
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Li W, Xu D, Zhang Z, Xu Y. Synthesis and Properties of Novel Aromatic Azo Compounds from Hydroxyazobenzene and Cyanuric Chloride. CHINESE J CHEM 2012. [DOI: 10.1002/cjoc.201200209] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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21
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Sun H, Chen X, Chen D, Dong M, Fu X, Li Q, Liu X, Wu Q, Qiu T, Wan T, Li S. Influences of surface coatings and components of FePt nanoparticles on the suppression of glioma cell proliferation. Int J Nanomedicine 2012; 7:3295-307. [PMID: 22848161 PMCID: PMC3405879 DOI: 10.2147/ijn.s32678] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
Abstract
Malignant gliomas are primary brain tumors with high rates of morbidity and mortality; they are the fourth most common cause of cancer death. Novel diagnostic and therapeutic techniques based on nanomaterials provide promising options in the treatment of malignant gliomas. In order to evaluate the potential of FePt nanoparticles (NPs) for malignant glioma therapy, FePt NPs with different surface coatings and components were tunably synthesized using oleic acid/oleylamine (OA/OA) and cysteines (Cys) as the capping agents, respectively. The samples were characterized using X-ray diffraction, transmission electron microscopy (TEM), X-ray photon spectroscopy, Fourier transform infrared spectroscopy, atomic absorption spectrum, and zeta potential. The influence of the surface coatings and components of the FePt NPs on the proliferation of glioma cells was assessed through MTT assay and TEM observation using three typical glioma cell lines (glioma U251 cells, astrocytoma U87 cells, and neuroglioma H4 cells) as in vitro models. The results showed that the proliferation of glioma cells was significantly suppressed by lipophilic FePt-OA/OA NPs in a time- and/or dose-dependent manner, while no or low cytotoxic effects were detected in the case of hydrophilic FePt-Cys NPs. The IC₅₀ value of FePt-OA/OA NPs on the three glioma cell lines was approximately 5-10 μg mL⁻¹ after 24 hours' incubation. Although the cellular uptake of FePt NPs was confirmed regardless of the surface coatings and components of the FePt NPs, the suppression of FePt NPs on glioma cell proliferation was dominantly determined by their surface coatings rather than their components. Therefore, these results demonstrate that, through engineering of the surface coating, FePt NPs can potentially be developed as novel therapeutic agents for malignant gliomas.
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Affiliation(s)
- Haiming Sun
- State Key Laboratory of Advanced Technology for Materials Synthesis and Processing and Biomedical Materials and Engineering Center, Wuhan University of Technology, Wuhan, China
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Nealon GL, Greget R, Dominguez C, Nagy ZT, Guillon D, Gallani JL, Donnio B. Liquid-crystalline nanoparticles: Hybrid design and mesophase structures. Beilstein J Org Chem 2012; 8:349-70. [PMID: 22509204 PMCID: PMC3326612 DOI: 10.3762/bjoc.8.39] [Citation(s) in RCA: 107] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2011] [Accepted: 02/09/2012] [Indexed: 01/28/2023] Open
Abstract
Liquid-crystalline nanoparticles represent an exciting class of new materials for a variety of potential applications. By combining supramolecular ordering with the fluid properties of the liquid-crystalline state, these materials offer the possibility to organise nanoparticles into addressable 2-D and 3-D arrangements exhibiting high processability and self-healing properties. Herein, we review the developments in the field of discrete thermotropic liquid-crystalline nanoparticle hybrids, with special emphasis on the relationship between the nanoparticle morphology and the nature of the organic ligand coating and their resulting phase behaviour. Mechanisms proposed to explain the supramolecular organisation of the mesogens within the liquid-crystalline phases are discussed.
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Affiliation(s)
- Gareth L Nealon
- Institut de Physique et Chimie des Matériaux de Strasbourg (IPCMS), CNRS-Université de Strasbourg (UMR 7504), 23 rue du Loess, BP 43, 67034 Strasbourg Cedex 2, France
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23
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Jacquart A, Williams RM, Brouwer AM, Ishow E. Decoupling fluorescence and photochromism in bifunctional azo derivatives for bulk emissive structures. Chemistry 2012; 18:3706-20. [PMID: 22322661 DOI: 10.1002/chem.201103411] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2011] [Indexed: 11/08/2022]
Abstract
Bifunctional molecules that combine independent push-pull fluorophores and azo photochromes have been synthesized to create fluorescent structures upon light-induced migration in neat thin films. Their photochromic and emissive properties have been systematically investigated and interpreted in light of those of the corresponding model compounds. Fluorescence lifetimes and photoisomerization and fluorescence quantum yields have been determined in toluene solution. Kinetic analyses of the femtosecond transient absorption spectra reveal that the fluorophores evolve in a few picoseconds into a distorted intramolecular charge-transfer excited state, strongly stabilized in energy. Radiative relaxation to the ground state occurred competitively with the energy-transfer process to the azo moiety. Introduction of a 10 Å-long rigid and nonconjugated bridge between the photoactive units efficiently inhibits the energy transfer while it imparts enhanced free volume, which favors photoactivated molecular migration in the solid state.
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Affiliation(s)
- Aurélie Jacquart
- PPSM-UMR CNRS 8531, ENS Cachan, 61 avenue du Président Wilson, 94235 Cachan cedex, France
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24
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Shah SM, Martini C, Ackermann J, Fages F. Photoswitching in azobenzene self-assembled monolayers capped on zinc oxide: nanodots vs nanorods. J Colloid Interface Sci 2011; 367:109-14. [PMID: 22082797 DOI: 10.1016/j.jcis.2011.10.045] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2011] [Revised: 09/05/2011] [Accepted: 10/17/2011] [Indexed: 11/29/2022]
Abstract
We report the synthesis and spectroscopic characterization of nanohybrid structures consisting of an azobenzene compound grafted on the surface of zinc oxide nanoparticles. Characteristic bathochromic shifts indicate that the azobenzene photochromic molecules self-assemble onto the surface of the nanocrystals. The extent of packing is dependent on the shape of the nanoparticle. ZnO nanorods, with flat facets, enable a tighter organization of the molecules in the self-assembled monolayer than in the case of nanodots that display a more curvated shape. Consistently, the efficiency of photochromic switching of the self-assembled monolayer on ZnO nanoparticles is also shown to be strongly affected by nanoparticle shape.
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Affiliation(s)
- Syed Mujtaba Shah
- CINaM, UPR 3118 CNRS - Université de la Méditerranée, Campus de Luminy, Case 913, Marseille 13288, France.
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25
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Nakanishi H, Walker DA, Bishop KJM, Wesson PJ, Yan Y, Soh S, Swaminathan S, Grzybowski BA. Dynamic internal gradients control and direct electric currents within nanostructured materials. NATURE NANOTECHNOLOGY 2011; 6:740-746. [PMID: 22002098 DOI: 10.1038/nnano.2011.165] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/17/2011] [Accepted: 09/06/2011] [Indexed: 05/31/2023]
Abstract
Switchable nanomaterials--materials that can change their properties and/or function in response to external stimuli-have potential applications in electronics, sensing and catalysis. Previous efforts to develop such materials have predominately used molecular switches that can modulate their properties by means of conformational changes. Here, we show that electrical conductance through films of gold nanoparticles coated with a monolayer of charged ligands can be controlled by dynamic, long-range gradients of both mobile counterions surrounding the nanoparticles and conduction electrons on the nanoparticle cores. The internal gradients and the electric fields they create are easily reconfigurable, and can be set up in such a way that electric currents through the nanoparticles can be modulated, blocked or even deflected so that they only pass through select regions of the material. The nanoion/counterion hybrids combine the properties of electronic conductors with those of ionic gels/polymers, are easy to process by solution-casting and, by controlling the internal gradients, can be reconfigured into different electronic elements (current rectifiers, switches and diodes).
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Affiliation(s)
- Hideyuki Nakanishi
- Department of Chemical and Biological Engineering, Northwestern University, 2145 Sheridan Road, Evanston, Illinois 60208, USA
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26
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Indrianingsih AW, Suda M, Heta Y, Suzuki K, Einaga Y. Surface Modification of Ferromagnetic L1o FePt Nanoparticles Using Biotin–Avidin as Biomolecular Recognition Probes. BULLETIN OF THE CHEMICAL SOCIETY OF JAPAN 2011. [DOI: 10.1246/bcsj.20110086] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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27
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Matsushita T, Iwamoto T, Inokuchi M, Toshima N. Novel ferromagnetic materials of SmCo5 nanoparticles in single-nanometer size: chemical syntheses and characterizations. NANOTECHNOLOGY 2010; 21:095603. [PMID: 20110586 DOI: 10.1088/0957-4484/21/9/095603] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
We first succeeded in preparing ferromagnetic materials of SmCo(5) nanoparticles in sizes of single nanometers by a chemical route using a polyol process. In order to produce ferromagnetic SmCo(5) nanoparticles with a CaCu(5)-type structure, the chemical preparation was conducted under a molar ratio of 1:1.3 of Sm:Co as compositions of metallic precursors when tetraethylene glycol (TEG), and oleic acid and oleylamine were used as a reductant and protectant, respectively. However, XRD profiles of the products showed the presence of oxides and other by-products besides the CaCu(5)-type structured nanoparticles. The best metallic precursors and protective reagent to prevent oxidization under reaction were SmCl(3) and Co(acac)(3), and 1-adamantanecarboxylic acid (ACA) and poly(N-vinyl-2-pyrrolidone) (PVP), respectively when TEG was used as the reducing reagent. We found that oxides and other by-products were not detected and pure SmCo(5) nanoparticles with the CaCu(5)-type structure were prepared under the chemical condition. The SmCo(5) nanoparticles coated by ACA and PVP were 6.2 nm in diameter and showed a coercivity of 1500 Oe at 300 K.
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Affiliation(s)
- Toru Matsushita
- Department of Applied Chemistry, Faculty of Engineering, Tokyo University of Science Yamaguchi, Yamaguchi, Japan
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28
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Tsujioka T, Irie M. Electrical functions of photochromic molecules. JOURNAL OF PHOTOCHEMISTRY AND PHOTOBIOLOGY C-PHOTOCHEMISTRY REVIEWS 2010. [DOI: 10.1016/j.jphotochemrev.2010.02.001] [Citation(s) in RCA: 96] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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29
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Wu S, Shen J, Huang J, Wu Y, Zhang Z, Hu Y, Wu W, Huang W, Wang K, Zhang Q. Ag nanoparticle/azopolymer nanocomposites: In situ synthesis, microstructure, rewritable optically induced birefringence and optical recording. POLYMER 2010. [DOI: 10.1016/j.polymer.2010.01.062] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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Mair L, Ford K, Alam MDR, Kole R, Fisher M, Superfine R. Size-uniform 200 nm particles: fabrication and application to magnetofection. J Biomed Nanotechnol 2010; 5:182-91. [PMID: 20055096 DOI: 10.1166/jbn.2009.1024] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
We report on the fabrication of arrays of mono- and multimetallic particles via metal evaporation onto lithographically patterned posts, as well as the magnetic force calibration and successful magnetofection of iron particles grown via this method. This work represents the first instance in which metal evaporation onto post structures was used for the formation of released, shape-defined metal particles. Also, our work represents the first use of lithographically defined particles as agents of magnetofection. Using these techniques it is possible to create particles with complex shapes and lateral dimensions as small as 40 nm. Our demonstrated compositionally flexible particles are highly size-uniform due to their photolithographically defined growth substrates, with particle dimensions along two axes fixed at 200 nm; the third axis dimension can be varied from 20 nm to 300 nm during the deposition procedure. Atomic percent of metals incorporated into the particle volume is highly tunable and particles have been synthesized with as many as four different metals. We performed magnetic force calibrations on a single particle size for iron particles using an axially magnetized NeFeB permanent magnet and comparisons are made with commercially available magnetic beads. In order to evalutate their usefulness as magnetofection agents, an antisense oligonucleotide (ODN) designed to correct the aberrant splicing of enhanced green fluorescent protein mRNA, was successfully transfected into a modified HeLa cell line. Magnetically enhanced gene delivery was accomplished in vitro using antisense ODN-laden iron particles followed by application of a field gradient. Magnetically enhanced transfection resulted in a 76% and 139% increase in fluorescence intensity when compared to Lipofectamine and antisense ODN-loaded particles delivered without magnetic treatment, respectively. To our knowledge, these experiments constitute the first use of lithographically defined particles as successful agents for magnetically enhanced transfection of an antisense oligonucleotide.
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Affiliation(s)
- Lamar Mair
- Curriculum in Applied Sciences and Engineering, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599, USA
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31
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Klajn R, Stoddart JF, Grzybowski BA. Nanoparticles functionalised with reversible molecular and supramolecular switches. Chem Soc Rev 2010; 39:2203-37. [DOI: 10.1039/b920377j] [Citation(s) in RCA: 456] [Impact Index Per Article: 32.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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32
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Suda M, Kameyama N, Ikegami A, Suzuki M, Kawamura N, Einaga Y. Size-reduction induced ferromagnetism and photo-magnetic effects in azobenzene-thiol-passivated gold nanoparticles. Polyhedron 2009. [DOI: 10.1016/j.poly.2008.10.021] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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33
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Xu W, Wang Y, Xiao Y, Liu F, Lu GY. Langmuir monolayer and Langmuir-Blodgett films formed by a melamine-headed azobenzene-derived amphiphile: interfacial assembly affected by host-guest interaction. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2009; 25:3646-3651. [PMID: 19708147 DOI: 10.1021/la8039708] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
A novel azobenzene-derived amphiphile with a melamine head, 2Azo-2C12H2-melamine, has been synthesized. pi-A isotherm measurements displayed that this amphiphile is able to form a stable Langmuir monolayer on both pure water and barbituric acid (BA)- or thymine (T)-containing subphases. The collapse surface pressure and limiting molecular area of its Langmuir monolayer on pure water are 40 mN/m and 0.56 nm2, respectively. However, when barbituric acid or thymine was introduced into the subphase, the corresponding pi-A isotherms of the monolayers exhibited a lower collapse surface pressure (22 mN/m for BA, 21 mN/m for T) and smaller limiting molecular area (0.54 nm2 for BA and 0.52 nm2 for T). UV-vis and FT-IR studies of the LB films formed by 2Azo-2C12H25-melamine have also been carried out. The results indicated that the LB films of 2Azo-2C12H25-melamine deposited from pure water undergo distinct collapse of the H-aggregate upon UV irradiation, while the LB films deposited from a BA- or T-containing subphase retain the H-aggregate. The host-guest-interaction-induced blockage of azobenzene photoisomerization should be responsible for the stabilized H-aggregate. A 1:1 host/guest binding mode to form a linear supramolecular polymeric chain has been proposed in the Langmuir monolayers formed on a BA- or T-containing subphase. The current results suggest that the host-guest interaction should be an effective means to manipulate the interfacial assembly of azobenzene-derived amphiphiles.
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Affiliation(s)
- Weihong Xu
- State Key Laboratory of Coordination Chemistry, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing 210093, People's Republic of China
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34
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Suda M, Einaga Y. Sequential Assembly of Phototunable Ferromagnetic Ultrathin Films with Perpendicular Magnetic Anisotropy. Angew Chem Int Ed Engl 2009. [DOI: 10.1002/ange.200804894] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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35
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Suda M, Einaga Y. Sequential Assembly of Phototunable Ferromagnetic Ultrathin Films with Perpendicular Magnetic Anisotropy. Angew Chem Int Ed Engl 2009; 48:1754-7. [DOI: 10.1002/anie.200804894] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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36
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Suda M, Kameyama N, Ikegami A, Einaga Y. Reversible Phototuning of the Large Anisotropic Magnetization at the Interface between a Self-Assembled Photochromic Monolayer and Gold. J Am Chem Soc 2008; 131:865-70. [DOI: 10.1021/ja808231c] [Citation(s) in RCA: 59] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Masayuki Suda
- Department of Chemistry, Faculty of Science and Technology, Keio University, 3-14-1 Hiyoshi, Yokohama 223-8522, Japan
| | - Naoto Kameyama
- Department of Chemistry, Faculty of Science and Technology, Keio University, 3-14-1 Hiyoshi, Yokohama 223-8522, Japan
| | - Aya Ikegami
- Department of Chemistry, Faculty of Science and Technology, Keio University, 3-14-1 Hiyoshi, Yokohama 223-8522, Japan
| | - Yasuaki Einaga
- Department of Chemistry, Faculty of Science and Technology, Keio University, 3-14-1 Hiyoshi, Yokohama 223-8522, Japan
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Nazir R, Mazhar M, Akhtar MJ, Raza Shah M, Khan NA, Nadeem M, Siddique M, Mehmood M, Butt NM. Superparamagnetic bimetallic iron-palladium nanoalloy: synthesis and characterization. NANOTECHNOLOGY 2008; 19:185608. [PMID: 21825696 DOI: 10.1088/0957-4484/19/18/185608] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
Iron-palladium nanoalloy in the particle size range of 15-30 nm is synthesized by the relatively low temperature thermal decomposition of coprecipitated [Fe(Bipy)(3)]Cl(2) and [Pd(Bipy)(3)]Cl(2) in an inert ambient of dry argon gas. The silvery black Fe-Pd alloy nanoparticles are air-stable and have been characterized by EDX-RF, XRD, AFM, TEM, magnetometry, (57)Fe Mössbauer and impedance spectroscopy. This Fe-Pd nanoalloy is in single phase and contains iron sites having up to 11 nearest-neighboring atoms. It is superparamagnetic in nature with high magnetic susceptibility, low coercivity and hyperfine field.
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Affiliation(s)
- Rabia Nazir
- Department of Chemistry, Quaid-i-Azam University, Islamabad 45320, Pakistan
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38
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Suda M, Kameyama N, Suzuki M, Kawamura N, Einaga Y. Reversible Phototuning of Ferromagnetism at Au–S Interfaces at Room Temperature. Angew Chem Int Ed Engl 2008; 47:160-3. [DOI: 10.1002/anie.200704027] [Citation(s) in RCA: 68] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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39
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Suda M, Kameyama N, Suzuki M, Kawamura N, Einaga Y. Reversible Phototuning of Ferromagnetism at Au–S Interfaces at Room Temperature. Angew Chem Int Ed Engl 2008. [DOI: 10.1002/ange.200704027] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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40
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Min Yeo K, Ji Gao C, Ahn KH, Su Lee I. Superparamagnetic iron oxide nanoparticles with photoswitchable fluorescence. Chem Commun (Camb) 2008:4622-4. [DOI: 10.1039/b807462c] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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41
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Crouse CA, Barron AR. Reagent control over the size, uniformity, and composition of Co–Fe–O nanoparticles. ACTA ACUST UNITED AC 2008. [DOI: 10.1039/b806686h] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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42
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Namiki K, Sakamoto A, Murata M, Kume S, Nishihara H. Reversible photochromism of a ferrocenylazobenzene monolayer controllable by a single green light source. Chem Commun (Camb) 2007:4650-2. [DOI: 10.1039/b713107k] [Citation(s) in RCA: 49] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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