101
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Modeling Self-Assembly Across Scales: The Unifying Perspective of Smart Minimal Particles. MICROMACHINES 2011. [DOI: 10.3390/mi2020082] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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102
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Chung SE, Jung Y, Kwon S. Three-dimensional fluidic self-assembly by axis translation of two-dimensionally fabricated microcomponents in railed microfluidics. SMALL (WEINHEIM AN DER BERGSTRASSE, GERMANY) 2011; 7:796-803. [PMID: 21322106 DOI: 10.1002/smll.201001806] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/12/2010] [Revised: 11/23/2010] [Indexed: 05/30/2023]
Abstract
A method for high-throughput 3D self-assembly of 2D photopatterned microstructures using railed microfluidics is presented. Vertical device patterning of heterogeneous materials requires high-level integration using conventional microelectromechanical system (MEMS) technology; however, 3D railed assembly enables easy and fast self-assembly via a fluidic axis-translation process and simple material exchange in microfluidic channels. Individually photopatterned 2D microstructures are axis-translated from in-plane to out-of-plane and fluidically self-assembled, guided by side-rails in microfluidic channels to form a 3D morphology. Since the structures are fabricated in fluidic environments, there are no fixed initial points on the channel substrate allowing fluidic horizontal stacking of erected 2D structures. The guiding mechanism of railed microfluidics enables efficient fluidic handling and deterministic 3D self-assembly of heterogeneous components such as electronic components or polymeric microstructures using only fluidic force.
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Affiliation(s)
- Su Eun Chung
- School of Electrical Engineering and Computer Science, College of Engineering, Seoul National University, 599 Gwanangno, Gwanak-gu, Seoul 151-744, South Korea
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103
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Self-Assembly of Microscale Parts through Magnetic and Capillary Interactions. MICROMACHINES 2011. [DOI: 10.3390/mi2010069] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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104
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Self-Assembly of Chip-Size Components with Cavity Structures: High-Precision Alignment and Direct Bonding without Thermal Compression for Hetero Integration. MICROMACHINES 2011. [DOI: 10.3390/mi2010049] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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105
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Mogilevsky A, Jelinek R. Gold nanoparticle self-assembly in two-component lipid Langmuir monolayers. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2011; 27:1260-1268. [PMID: 21050012 DOI: 10.1021/la103718v] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
Self-assembly processes are considered to be fundamental factors in supramolecular chemistry. Langmuir monolayers of surfactants or lipids have been shown to constitute effective 2D "templates" for self-assembled nanoparticles and colloids. Here we show that alkyl-coated gold nanoparticles (Au NPs) adopt distinct configurations when incorporated within Langmuir monolayers comprising two lipid components at different mole ratios. Thermodynamic and microscopy analyses reveal that the organization of the Au NP aggregates is governed by both lipid components. In particular, we show that the configurations of the NP assemblies were significantly affected by the extent of molecular interactions between the two lipid components within the monolayer and the monolayer phases formed by each individual lipid. This study demonstrates that multicomponent Langmuir monolayers significantly modulate the self-assembly properties of embedded Au NPs and that parameters such as the monolayer composition, surface pressure, and temperature significantly affect the 2D nanoparticle organization.
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Affiliation(s)
- Alina Mogilevsky
- Ilse Katz Institute for Nanotechnology, Ben Gurion University, Beer Sheva, Israel
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106
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Miyashita S, Göldi M, Pfeifer R. How reverse reactions influence the yield of self-assembly robots. Int J Rob Res 2011. [DOI: 10.1177/0278364910393288] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
The decay in structure size of manufacturing products has yielded new demands on spontaneous composition methods. The key for the realization of small-sized robots lies in how to achieve the efficient assembly sequence in a bottom-up manner, where most of the parts have only limited (or no) computational (i.e. deliberative) abilities. In this paper, based on a novel self-assembly platform consisting of self-propulsive centimetre-sized modules capable of aggregation on the surface of water, we study the effect of stochasticity and morphology (shape) on the yield of targeted formations in self-assembly processes. Specifically, we focus on a unique phenomenon: that a number of modules instantly compose a target product without forming intermediate subassemblies, some of which constitute undesired geometrical formations (termed one-shot aggregation). Together with a focus on the role that the morphology of the modules plays, we validate the effect of one-shot aggregation with a kinetic rate mathematical model. Moreover, we examined the degree of parallelism of the assembly process, which is an essential factor in self-assembly, but is not systematically taken into account by existing frameworks.
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Affiliation(s)
- Shuhei Miyashita
- Artificial Intelligence Laboratory, University of Zurich, Switzerland,
| | - Maurice Göldi
- Artificial Intelligence Laboratory, University of Zurich, Switzerland
| | - Rolf Pfeifer
- Artificial Intelligence Laboratory, University of Zurich, Switzerland
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107
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Lone S, Kim SH, Nam SW, Park S, Joo J, Cheong IW. Microfluidic synthesis of Janus particles by UV-directed phase separation. Chem Commun (Camb) 2011; 47:2634-6. [PMID: 21234478 DOI: 10.1039/c0cc04517a] [Citation(s) in RCA: 66] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
A synthetic methodology based on microfluidics has been developed to fabricate monodisperse polymer Janus particles by UV-directed phase separation.
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Affiliation(s)
- Saifullah Lone
- Department of Applied Chemistry, Kyungpook National University, Daegu, South Korea
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108
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Chen L, Henein G, Luciani V. Nanofabrication techniques for controlled drug-release devices. Nanomedicine (Lond) 2011; 6:1-6. [DOI: 10.2217/nnm.10.140] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Affiliation(s)
- Lei Chen
- Center for Nanoscale Science & Technology, National Institute of Standards & Technology, 100 Bureau Drive, Stop 6201, Gaithersburg, MD 20899-6201, USA
| | - Gerard Henein
- Center for Nanoscale Science & Technology, National Institute of Standards & Technology, 100 Bureau Drive, Stop 6201, Gaithersburg, MD 20899-6201, USA
| | - Vincent Luciani
- Center for Nanoscale Science & Technology, National Institute of Standards & Technology, 100 Bureau Drive, Stop 6201, Gaithersburg, MD 20899-6201, USA
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109
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110
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Jiang XC, Zeng QH, Chen CY, Yu AB. Self-assembly of particles: some thoughts and comments. ACTA ACUST UNITED AC 2011. [DOI: 10.1039/c1jm12213d] [Citation(s) in RCA: 44] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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111
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Kondratenko YV, Seebauer EG. Directed self-assembly by photostimulation of an amorphous semiconductor surface. AIChE J 2010. [DOI: 10.1002/aic.12229] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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112
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Bali R, Harris AT. Biogenic Synthesis of Au Nanoparticles Using Vascular Plants. Ind Eng Chem Res 2010. [DOI: 10.1021/ie101600m] [Citation(s) in RCA: 60] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
Affiliation(s)
- Roza Bali
- Laboratory for Sustainable Technology, School of Chemical and Biomolecular Engineering, University of Sydney, NSW, 2006, Australia
| | - Andrew T. Harris
- Laboratory for Sustainable Technology, School of Chemical and Biomolecular Engineering, University of Sydney, NSW, 2006, Australia
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113
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Cho JH, Azam A, Gracias DH. Three dimensional nanofabrication using surface forces. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2010; 26:16534-9. [PMID: 20507147 PMCID: PMC2948580 DOI: 10.1021/la1013889] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/25/2023]
Abstract
We describe strategies to curve, rotate, align, and bond precisely patterned two-dimensional (2D) nanoscale panels using forces derived from a minimization of surface area of liquefying or coalescing metallic grains. We demonstrate the utility of this approach by discussing variations in template size, patterns, and material composition. The strategy provides a solution path to overcome the limitation of inherently 2D lithographic processes by transforming 2D templates into mechanically robust and precisely patterned nanoscale curved structures and polyhedra with considerable versatility in material composition.
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Affiliation(s)
- Jeong-Hyun Cho
- Department of Chemical and Biomolecular Engineering, Johns Hopkins University, 3400 North Charles Street, Baltimore, Maryland 21218, USA
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114
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Randhawa JS, Kanu LN, Singh G, Gracias DH. Importance of surface patterns for defect mitigation in three-dimensional self-assembly. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2010; 26:12534-12539. [PMID: 20597527 DOI: 10.1021/la101188z] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/29/2023]
Abstract
This article investigates the three-dimensional self-assembly of submillimeter scale polyhedra using surface forces. Using a combination of energy landscape calculations and experiments, we investigate the influence of patterns of hydrophobic surfaces on generating defect-free, closed-packed aggregates of polyhedra, with a focus on cubic units. Calculations show that surface patterning strongly affects the interaction between individual units as well as that of the unit with the growing assembly. As expected, an increase in the hydrophobic surface area on each face results in larger global minima. However, it is the distribution of hydrophobic surface area on each cubic face that is strongly correlated to the energetic parameters driving low-defect assembly. For patterns with the same overall area, minimizing the radius of gyration and maximizing the angular distribution leads to steep energy curves, with a lower propensity for entrapment in metastable states. Experimentally, 200-500 microm sized metallic polyhedra were fabricated using a self-folding process, and the exposed surfaces were coated with a hydrophobic polymer. Cubes with surface patterns were agitated to cause aggregative self-assembly. Experimental results were consistent with energy calculations and suggest that geometric patterns with large overall areas, low radii of gyration, and high angular distributions result in efficient and low-defect assembly.
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Affiliation(s)
- Jatinder S Randhawa
- Department of Chemical and Biomolecular Engineering, Johns Hopkins University, 3400 N. Charles St., Baltimore, Maryland 21218, USA
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115
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Bufon CCB, González JDC, Thurmer DJ, Grimm D, Bauer M, Schmidt OG. Self-assembled ultra-compact energy storage elements based on hybrid nanomembranes. NANO LETTERS 2010; 10:2506-2510. [PMID: 20536208 DOI: 10.1021/nl1010367] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/29/2023]
Abstract
Self-assembly methods combined with standard top-down approaches are demonstrated to be suitable for fabricating three-dimensional ultracompact hybrid organic/inorganic electronic devices based on rolled-up nanomembranes. Capacitors that are self-wound and manufactured in parallel are almost 2 orders of magnitude smaller than their planar counterparts and exhibit capacitances per footprint area of around 200 microF/cm(2). This value significantly exceeds that which was previously reported for metal-insulator-metal capacitors based on Al(2)O(3), and the obtained specific energy (approximately 0.55 Wh/kg) would allow their usage as ultracompact supercapacitors. By incorporating organic monolayers into the inorganic nanomembrane structure we can precisely control the electronic characteristics of the devices. The adaptation of the process for creating ultracompact batteries, coils and transformers is an attractive opportunity for reducing the size of energy storage elements, filters, and signal converters. These devices can be employed as implantable electronic circuits or new approaches for energy-harvesting applications. Furthermore, the incorporation of functional organic molecules gives rise to novel devices with almost limitless chemical and biological functionalities.
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116
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Fernandez JG, Khademhosseini A. Micro-masonry: construction of 3D structures by microscale self-assembly. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2010; 22:2538-41. [PMID: 20440697 PMCID: PMC2957829 DOI: 10.1002/adma.200903893] [Citation(s) in RCA: 65] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/20/2023]
Affiliation(s)
- Javier G Fernandez
- Center for Biomedical Engineering, Department of Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, USA
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117
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Wu Y, Zhang C, Qu X, Liu Z, Yang Z. Light-triggered reversible phase transfer of composite colloids. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2010; 26:9442-9448. [PMID: 20420440 DOI: 10.1021/la100458j] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/29/2023]
Abstract
Composite colloids were prepared via grafting optically responsive spiropyran polymer brushes onto silica colloids. Similar to spiropyran, the polymer brushes undergo a reversible inversion from a hydrophobic state to a hydrophilic state upon irradiation with UV light (or vice versa by visible light). The composite colloids can thus reversibly transfer between oil and water phases, and this can be remotely triggered using light. At intermediate stages of irradiation, both hydrophobic and hydrophilic components coexist, resulting in the amphiphilic performance of the composite colloids. Such amphiphilic composite colloids can be used as particulate emulsifiers.
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Affiliation(s)
- Ying Wu
- State Key Laboratory of Polymer Physics and Chemistry, Institute of Chemistry, Chinese Academy of Science, Beijing 100190, China
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118
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Mogilevsky A, Volinsky R, Dayagi Y, Markovich N, Jelinek R. Gold nanoparticle self-assembly in saturated phospholipid monolayers. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2010; 26:7893-7898. [PMID: 20151702 DOI: 10.1021/la9047903] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
Self-assembly of nanostructures on surfaces is a promising area in the emerging field of "bottom-up nanolithography". We describe a systematic analysis of hydrophobically capped gold nanoparticle (Au NP) assemblies created within monolayers of saturated phospholipids deposited at the air/water interface. We show that the Au NPs are segregated within the mixed monolayers, forming distinct configurations. Microscopy analysis reveals that organized Au NP aggregates, including wires, rings, and "doughnut-shape" structures, are observed only within condensed-phase monolayers comprising phospholipids exhibiting longer acyl side-chains. In these monolayers, the Au NPs are localized at the edges of the condensed phospholipid domains. In addition to the pronounced effect of the phospholipid phases at the air/water interface, NP organization was found to depend upon the hydrophobic capping agents of the particles. The Au nanostructures assembled at the air/water interface can be transferred onto solid substrates, suggesting that the self-assembly monolayer approach could be exploited for practical nanoelectronic and sensing applications.
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Affiliation(s)
- Alina Mogilevsky
- Ilse Katz Institute for Nanotechnology and Department of Chemistry, Ben Gurion University, Beer Sheva 84105, Israel
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119
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Dong L, Liu Y, Zhuo Y, Chu Y. General Route to the Fabrication of ZnS and M-Doped (M = Cd2+, Mn2+, Co2+, Ni2+, and Eu3+) ZnS Nanoclews and a Study of Their Properties. Eur J Inorg Chem 2010. [DOI: 10.1002/ejic.201000054] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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120
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Leong TG, Zarafshar AM, Gracias DH. Three-dimensional fabrication at small size scales. SMALL (WEINHEIM AN DER BERGSTRASSE, GERMANY) 2010; 6:792-806. [PMID: 20349446 PMCID: PMC3078552 DOI: 10.1002/smll.200901704] [Citation(s) in RCA: 70] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/19/2023]
Abstract
Despite the fact that we live in a 3D world and macroscale engineering is 3D, conventional submillimeter-scale engineering is inherently 2D. New fabrication and patterning strategies are needed to enable truly 3D-engineered structures at small size scales. Here, strategies that have been developed over the past two decades that seek to enable such millimeter to nanoscale 3D fabrication and patterning are reviewed. A focus is the strategy of self-assembly, specifically in a biologically inspired, more deterministic form, known as self-folding. Self-folding methods can leverage the strengths of lithography to enable the construction of precisely patterned 3D structures and "smart" components. This self-assembly approach is compared with other 3D fabrication paradigms, and its advantages and disadvantages are discussed.
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Affiliation(s)
- Timothy G. Leong
- Department of Chemical and Biomolecular Engineering, The Johns Hopkins University 3400 N Charles St. Baltimore, MD 21218 (USA)
| | - Aasiyeh M. Zarafshar
- Department of Chemical and Biomolecular Engineering, The Johns Hopkins University 3400 N Charles St. Baltimore, MD 21218 (USA)
| | - David H. Gracias
- Department of Chemical and Biomolecular Engineering, The Johns Hopkins University 3400 N Charles St. Baltimore, MD 21218 (USA)
- Department of Chemistry, The Johns Hopkins University 3400 N Charles St. Baltimore, MD 21218 (USA)
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121
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Miller MS, Davidson GJE, Carmichael TB. Templated self-assembly of glass microspheres into ordered two-dimensional arrays under dry conditions. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2010; 26:5286-5290. [PMID: 19916537 DOI: 10.1021/la903679x] [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
This paper describes a new approach to mesoscale self-assembly in which a stream of nitrogen is used to propel micrometer-scale components toward a template of patterned liquid adhesive drops. This approach combines the use of capillary forces to hold the components in place with dry processing conditions. Eliminating the use of a liquid medium to suspend components is an important goal for mesoscale self-assembly methods because it eliminates the need for special encapsulation to protect electrically functional components. We demonstrate the dry self-assembly approach by assembling 100 microm glass microspheres into a variety of 2D patterns. A study of defects in these arrays relates parameters associated with the template--density of binding sites and volume of liquid adhesive comprising the drops--to the frequency of defects arising from the incorporation of additional microspheres into the array. Optimized template parameters and self-assembly conditions yield 2D arrays with defect rates of approximately 4-5%. We also demonstrate the versatility of this self-assembly method by producing ordered binary arrays of clear and black glass microspheres.
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Affiliation(s)
- Michael S Miller
- Department of Chemistry and Biochemistry, University of Windsor, Windsor, Ontario, Canada N9B 3P4
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122
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Choi S, Park I, Hao Z, Holman HYN, Pisano AP, Zohdi TI. Ultrafast self-assembly of microscale particles by open-channel flow. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2010; 26:4661-4667. [PMID: 19921822 DOI: 10.1021/la903492w] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
We developed an ultrafast microfluidic approach to self-assemble microparticles in three dimensions by taking advantage of simple photolithography and capillary action of microparticle-dispersed suspensions. The theoretical principles of high-speed assembly have been explained, and the experimental verifications of the assembly of various sizes of silica microspheres and silica gel microspheres within thin and long open microchannels by using this approach have been demonstrated. We anticipate that the presented technique will be widely used in the semiconductor and Bio-MEMS (microelectromechanical systems) fields because it offers a fast way to control 3D microscale particle assemblies and also has superb compatibility with photolithography, which can lead to an easy integration of particle assembly with existing CMOS (complementary metal oxide-semiconductor) and MEMS fabrication processes.
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Affiliation(s)
- Sun Choi
- Berkeley Sensor and Actuator Center, University of California at Berkeley, Berkeley, California 94720, USA.
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123
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Gao F, Gu Z. Nano-soldering of magnetically aligned three-dimensional nanowire networks. NANOTECHNOLOGY 2010; 21:115604. [PMID: 20179331 DOI: 10.1088/0957-4484/21/11/115604] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
It is extremely challenging to fabricate 3D integrated nanostructures and hybrid nanoelectronic devices. In this paper, we report a simple and efficient method to simultaneously assemble and solder nanowires into ordered 3D and electrically conductive nanowire networks. Nano-solders such as tin were fabricated onto both ends of multi-segmented nanowires by a template-assisted electrodeposition method. These nanowires were then self-assembled and soldered into large-scale 3D network structures by magnetic field assisted assembly in a liquid medium with a high boiling point. The formation of junctions/interconnects between the nanowires and the scale of the assembly were dependent on the solder reflow temperature and the strength of the magnetic field. The size of the assembled nanowire networks ranged from tens of microns to millimeters. The electrical characteristics of the 3D nanowire networks were measured by regular current-voltage (I-V) measurements using a probe station with micropositioners. Nano-solders, when combined with assembling techniques, can be used to efficiently connect and join nanowires with low contact resistance, which are very well suited for sensor integration as well as nanoelectronic device fabrication.
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Affiliation(s)
- Fan Gao
- Department of Chemical Engineering, University of Massachusetts Lowell, Lowell, MA 01854, USA
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124
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Magnetically driven three-dimensional manipulation and inductive heating of magnetic-dispersion containing metal alloys. Proc Natl Acad Sci U S A 2010; 107:4834-9. [PMID: 20194786 DOI: 10.1073/pnas.1001410107] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Fundamental to the development of three-dimensional microelectronic fabrication is a material that enables vertical geometries. Here we show low-melting-point metal alloys containing iron dispersions that can be remotely manipulated by magnetic fields to create vertical geometries and thus enable novel three-dimensional assemblies. These iron dispersions enhance the mechanical properties needed for strong, reliable interconnects without significantly altering the electrical properties of the alloys. Additionally, these iron dispersions act as susceptors for magnetic induction heating, allowing the rapid melting of these novel alloys at temperatures lower than those usually reported for conventional metal alloys. By localizing high temperatures and by reducing temperature excursions, the materials and methods described have potential in a variety of device fabrication applications.
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125
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Bedau MA, McCaskill JS, Packard NH, Rasmussen S. Living technology: exploiting life's principles in technology. ARTIFICIAL LIFE 2010; 16:89-97. [PMID: 19857142 DOI: 10.1162/artl.2009.16.1.16103] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
The concept of living technology-that is, technology that is based on the powerful core features of life-is explained and illustrated with examples from artificial life software, reconfigurable and evolvable hardware, autonomously self-reproducing robots, chemical protocells, and hybrid electronic-chemical systems. We define primary (secondary) living technology according as key material components and core systems are not (are) derived from living organisms. Primary living technology is currently emerging, distinctive, and potentially powerful, motivating this review. We trace living technology's connections with artificial life (soft, hard, and wet), synthetic biology (top-down and bottom-up), and the convergence of nano-, bio-, information, and cognitive (NBIC) technologies. We end with a brief look at the social and ethical questions generated by the prospect of living technology.
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Affiliation(s)
- Mark A Bedau
- University of Southern Denmark, Odense, Denmark, USA.
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126
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Kim CR, Noh TH, Yoo KH, Yoo BR, Jung OS. Anionic Indicators on the Surface of Submicrospheres Consisting of Ionic Palladium(II) Complex. B KOREAN CHEM SOC 2009. [DOI: 10.5012/bkcs.2009.30.12.3057] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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127
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Abstract
The construction of three-dimensional (3D) objects, with any desired surface patterns, is both critical to and easily achieved in macroscale science and engineering. However, on the nanoscale, 3D fabrication is limited to particles with only very limited surface patterning. Here, we demonstrate a self-assembly strategy that harnesses the strengths of well-established 2D nanoscale patterning techniques and additionally enables the construction of stable 3D polyhedral nanoparticles. As a proof of the concept, we self-assembled cubic particles with sizes as small as 100 nm and with specific and lithographically defined surface patterns.
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Affiliation(s)
- Jeong-Hyun Cho
- Department of Chemical and Biomolecular Engineering, Johns Hopkins University, Baltimore, Maryland 21218, USA
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128
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Affiliation(s)
- Ki Wan Bong
- Department of Chemical Engineering, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, MA 02139, USA
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129
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130
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131
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Swellable Submicrospheres of Ionic Palladium(II) Complexes Containing Decylmethylbis(m-pyridyl)silane. B KOREAN CHEM SOC 2009. [DOI: 10.5012/bkcs.2009.30.10.2338] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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132
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Chung SE, Lee SA, Kim J, Kwon S. Optofluidic encapsulation and manipulation of silicon microchips using image processing based optofluidic maskless lithography and railed microfluidics. LAB ON A CHIP 2009; 9:2845-2850. [PMID: 19967123 DOI: 10.1039/b903760h] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
We demonstrate optofluidic encapsulation of silicon microchips using image processing based optofluidic maskless lithography and manipulation using railed microfluidics. Optofluidic maskless lithography is a dynamic photopolymerization technique of free-floating microstructures within a fluidic channel using spatial light modulator. Using optofluidic maskless lithography via computer-vision aided image processing, polymer encapsulants are fabricated for chip protection and guiding-fins for efficient chip conveying within a fluidic channel. Encapsulated silicon chips with guiding-fins are assembled using railed microfluidics, which is an efficient guiding and heterogeneous self-assembly system of microcomponents. With our technology, externally fabricated silicon microchips are encapsulated, fluidically guided and self-assembled potentially enabling low cost fluidic manipulation and assembly of integrated circuits.
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Affiliation(s)
- Su Eun Chung
- School of Electrical Engineering and Computer Science, Seoul National University, Seoul, 151-744, South Korea
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133
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Noh TH, Kim SA, Lee SY, Jung OS. Submicrosticks versus Submicrohelices by Sonication - Assembly of PdCl2Nanoparticles on Those Morphologies. Eur J Inorg Chem 2009. [DOI: 10.1002/ejic.200900698] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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134
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Chen L, Song Z, Wang X, Prikhodko SV, Hu J, Kodambaka S, Richards R. Three-dimensional morphology control during wet chemical synthesis of porous chromium oxide spheres. ACS APPLIED MATERIALS & INTERFACES 2009; 1:1931-1937. [PMID: 20355817 DOI: 10.1021/am900334q] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/29/2023]
Abstract
Controlling the morphological evolution in nanostructures is essential for improving their functionality, for example, in catalysis. Here, we demonstrate, using chromium oxide as a model system, that morphologies of functional binary oxide particles can be tailored by an efficient template-free synthetic approach. We construct a morphological "phase diagram" for chromium oxide spheres that shows the evolution of size and surface roughness as a function of the precursor and urea concentrations. It is notable that these chromium oxide spheres show an exceptional ability to remove azo-dye pollutant in water treatment. Thus, the porous chromium oxide spheres with very good dye absorptions are expected to be useful in alternative absorption technologies.
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Affiliation(s)
- Lifang Chen
- Department of Chemistry and Geochemistry, Colorado School of Mines, Golden, Colorado 80401, USA
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135
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Park W, Lee H, Park H, Kwon S. Sorting directionally oriented microstructures using railed microfluidics. LAB ON A CHIP 2009; 9:2169-2175. [PMID: 19606293 DOI: 10.1039/b904153b] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
We demonstrate the microfluidic sorting of directionally oriented (anisotropic) microstructures by their orientational state in solution using the concept of railed microfluidics. After being injected into a microfluidic channel, the microstructures rotate and flip in various directions. In order to sort microstructures in an organized way, we designed the microstructures and the microchannel to allow for orientation-based control of microstructure movement. In order to sort microstructures based on their rotation, we used a wedge shaped fin on the microstructures and a Y-shaped railed microfluidic channel. For sorting flipped particles, we use a double-railed microfluidic channel that has grooves on both its top and bottom surfaces. By integrating the two sorting methods we demonstrated high throughput, autonomous sorting into four different orientational states: unrotated-unflipped, rotated-unflipped, unrotated-flipped, and rotated-flipped. Here we not only demonstrate orientational assembly of directionally dependent microstructures, but also present design considerations for future work.
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Affiliation(s)
- Wook Park
- School of Electrical Engineering and Computer Science, Seoul National University, San 56-1, Sillim-dong, Gwanak-gu, Seoul, 151-744, Korea
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136
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Mastrangeli M, Abbasi S, Varel C, Van Hoof C, Celis JP, Böhringer KF. Self-assembly from milli- to nanoscales: methods and applications. JOURNAL OF MICROMECHANICS AND MICROENGINEERING : STRUCTURES, DEVICES, AND SYSTEMS 2009; 19:83001. [PMID: 20209016 PMCID: PMC2832205 DOI: 10.1088/0960-1317/19/8/083001] [Citation(s) in RCA: 76] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/20/2023]
Abstract
The design and fabrication techniques for microelectromechanical systems (MEMS) and nanodevices are progressing rapidly. However, due to material and process flow incompatibilities in the fabrication of sensors, actuators and electronic circuitry, a final packaging step is often necessary to integrate all components of a heterogeneous microsystem on a common substrate. Robotic pick-and-place, although accurate and reliable at larger scales, is a serial process that downscales unfavorably due to stiction problems, fragility and sheer number of components. Self-assembly, on the other hand, is parallel and can be used for device sizes ranging from millimeters to nanometers. In this review, the state-of-the-art in methods and applications for self-assembly is reviewed. Methods for assembling three-dimensional (3D) MEMS structures out of two-dimensional (2D) ones are described. The use of capillary forces for folding 2D plates into 3D structures, as well as assembling parts onto a common substrate or aggregating parts to each other into 2D or 3D structures, is discussed. Shape matching and guided assembly by magnetic forces and electric fields are also reviewed. Finally, colloidal self-assembly and DNA-based self-assembly, mainly used at the nanoscale, are surveyed, and aspects of theoretical modeling of stochastic assembly processes are discussed.
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137
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Filipiak DJ, Azam A, Leong TG, Gracias DH. Hierarchical self-assembly of complex polyhedral microcontainers. JOURNAL OF MICROMECHANICS AND MICROENGINEERING : STRUCTURES, DEVICES, AND SYSTEMS 2009; 19:1-6. [PMID: 20161118 PMCID: PMC2740998 DOI: 10.1088/0960-1317/19/7/075012] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
The concept of self-assembly of a two-dimensional (2D) template to a three-dimensional (3D) structure has been suggested as a strategy to enable highly parallel fabrication of complex, patterned microstructures. We have previously studied the surface tension based self-assembly of patterned, microscale polyhedral containers (cubes, square pyramids and tetrahedral frusta). In this paper, we describe the observed hierarchical self-assembly of more complex, patterned polyhedral containers in the form of regular dodecahedra and octahedra. The hierarchical design methodology, combined with the use of self-correction mechanisms, was found to greatly reduce the propagation of self-assembly error that occurs in these more complex systems. It is a highly effective way to mass-produce patterned, complex 3D structures on the microscale and could also facilitate encapsulation of cargo in a parallel and cost-effective manner. Furthermore, the behavior that we have observed may be useful in the assembly of complex systems with large numbers of components.
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Affiliation(s)
- David J. Filipiak
- Department of Chemical and Biomolecular Engineering, The Johns Hopkins University, Baltimore, Maryland 21218
| | - Anum Azam
- Department of Biomedical Engineering, The Johns Hopkins University, Baltimore, Maryland 21218
| | - Timothy G. Leong
- Department of Chemical and Biomolecular Engineering, The Johns Hopkins University, Baltimore, Maryland 21218
| | - David H. Gracias
- Department of Chemical and Biomolecular Engineering, The Johns Hopkins University, Baltimore, Maryland 21218
- Department of Chemistry, The Johns Hopkins University, Baltimore, Maryland 21218
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138
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Cui Q, Gao F, Mukherjee S, Gu Z. Joining and interconnect formation of nanowires and carbon nanotubes for nanoelectronics and nanosystems. SMALL (WEINHEIM AN DER BERGSTRASSE, GERMANY) 2009; 5:1246-1257. [PMID: 19387987 DOI: 10.1002/smll.200801551] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
Interconnect formation is critical for the assembly and integration of nanocomponents to enable nanoelectronics- and nanosystems-related applications. Recent progress on joining and interconnect formation of key nanomaterials, especially nanowires and carbon nanotubes, into functional circuits and/or prototype devices is reviewed. The nanosoldering technique through nanoscale lead-free solders is discussed in more detail in this Review. Various strategies of fabricating lead-free nanosolders and the utilization of the nanosoldering technique to form functional solder joints are reviewed, and related challenges facing the nanosoldering technique are discussed. A perspective is given for using lead-free nanosolders and the nanosoldering technique for the construction of complex and/or hybrid nanoelectronics and nanosystems.
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Affiliation(s)
- Qingzhou Cui
- Department of Chemical Engineering and CHN/NCOE Nanomanufacturing Center One University Ave. University of Massachusetts Lowell Lowell, MA 01854, USA
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139
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Di X, Kansal SK, Deng W. Preparation, characterization and photocatalytic activity of flowerlike cadmium sulfide nanostructure. Sep Purif Technol 2009. [DOI: 10.1016/j.seppur.2009.04.007] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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140
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Bong KW, Pregibon DC, Doyle PS. Lock release lithography for 3D and composite microparticles. LAB ON A CHIP 2009; 9:863-6. [PMID: 19294294 DOI: 10.1039/b821930c] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/11/2023]
Abstract
We present a method called "Lock Release Lithography (LRL)" that utilizes a combination of channel topography, mask design, and pressure-induced channel deformation to form and release particles in a cycled fashion. This technique provides a means for the high-throughput production of particles with complex 3D morphologies and composite particles with spatially configurable chemistries. In this work, we demonstrate a diverse set of functional particles including those displaying heterogeneous swelling characteristics and containing functional entities such as nucleic acids, proteins and beads.
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Affiliation(s)
- Ki Wan Bong
- Department of Chemical Engineering, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, MA 02139, USA
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141
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Azam A, Leong TG, Zarafshar AM, Gracias DH. Compactness determines the success of cube and octahedron self-assembly. PLoS One 2009; 4:e4451. [PMID: 19212438 PMCID: PMC2636878 DOI: 10.1371/journal.pone.0004451] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2008] [Accepted: 12/09/2008] [Indexed: 11/18/2022] Open
Abstract
Nature utilizes self-assembly to fabricate structures on length scales ranging from the atomic to the macro scale. Self-assembly has emerged as a paradigm in engineering that enables the highly parallel fabrication of complex, and often three-dimensional, structures from basic building blocks. Although there have been several demonstrations of this self-assembly fabrication process, rules that govern a priori design, yield and defect tolerance remain unknown. In this paper, we have designed the first model experimental system for systematically analyzing the influence of geometry on the self-assembly of 200 and 500 µm cubes and octahedra from tethered, multi-component, two-dimensional (2D) nets. We examined the self-assembly of all eleven 2D nets that can fold into cubes and octahedra, and we observed striking correlations between the compactness of the nets and the success of the assembly. Two measures of compactness were used for the nets: the number of vertex or topological connections and the radius of gyration. The success of the self-assembly process was determined by measuring the yield and classifying the defects. Our observation of increased self-assembly success with decreased radius of gyration and increased topological connectivity resembles theoretical models that describe the role of compactness in protein folding. Because of the differences in size and scale between our system and the protein folding system, we postulate that this hypothesis may be more universal to self-assembling systems in general. Apart from being intellectually intriguing, the findings could enable the assembly of more complicated polyhedral structures (e.g. dodecahedra) by allowing a priori selection of a net that might self-assemble with high yields.
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Affiliation(s)
- Anum Azam
- Department of Biomedical Engineering, The Johns Hopkins University, Baltimore, Maryland, United States of America
| | - Timothy G. Leong
- Department of Chemical and Biomolecular Engineering, The Johns Hopkins University, Maryland, United States of America
| | - Aasiyeh M. Zarafshar
- Department of Biomedical Engineering, The Johns Hopkins University, Baltimore, Maryland, United States of America
| | - David H. Gracias
- Department of Chemical and Biomolecular Engineering, The Johns Hopkins University, Maryland, United States of America
- Department of Chemistry, The Johns Hopkins University, Baltimore, Maryland, United States of America
- * E-mail:
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142
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Abstract
Although nanocrystals and nanowires have proliferated new scientific avenues in the study of their physics and chemistries, the bottom-up assembly of these small-scale building blocks remains a formidable challenge for device fabrication and processing. An attractive nanoscale assembly strategy should be cheap, fast, defect tolerant, compatible with a variety of materials, and parallel in nature, ideally utilizing the self-assembly to generate the core of a device, such as a memory chip or optical display. Langmuir-Blodgett (LB) assembly is a good candidate for arranging vast numbers of nanostructures on solid surfaces. In the LB technique, uniaxial compression of a nanocrystal or nanowire monolayer floating on an aqueous subphase causes the nanostructures to assemble and pack over a large area. The ordered monolayer can then be transferred to a solid surface en masse and with fidelity. In this Account, we present the Langmuir-Blodgett technique as a low-cost method for the massively parallel, controlled organization of nanostructures. The isothermal compression of fluid-supported nanoparticles or nanowires is unique in its ability to achieve control over nanoscale assembly by tuning a macroscopic property such as surface pressure. Under optimized conditions (e.g., surface pressure, substrate hydrophobicity, and pulling speed), it allows continuous variation of particle density, spacing, and even arrangement. For practical application and device fabrication, LB compression is ideal for forming highly dense assemblies of nanowires and nanocrystals over unprecedented surface areas. In addition, the dewetting properties of LB monolayers can be used to further achieve patterning within the range of micrometers to tens of nanometers without a predefined template. The LB method should allow for easy integration of nanomaterials into current manufacturing schemes, in addition to fast device prototyping and multiplexing capability.
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Affiliation(s)
- Andrea R. Tao
- Institute for Collaborative Biotechnologies, University of California, Santa Barbara, California 93106
| | - Jiaxing Huang
- Department of Materials Science and Engineering, Northwestern University, Evanston, Illinois 60208
| | - Peidong Yang
- Department of Chemistry, University of California, Berkeley, California 94720
- Materials Sciences Division, Lawrence Berkeley National Laboratory, 1 Cyclotron Road, Berkeley, California 94720
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143
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Feng X, Chandrasekhar N, Su H, Müllen K. Ballistic electron microscopy of nanographene layers. NANO LETTERS 2008; 8:4259-4264. [PMID: 19367800 DOI: 10.1021/nl801949g] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
We use scanning tunneling microscopy and ballistic electron emission spectroscopy and microscopy to study charge transport across Pt-nanographene-Pd interfaces. Four triangle-shaped nanographene molecules with different bulky substituents are studied. Modifications of highest occupied molecular orbital and lowest unoccupied molecular orbital levels resulting from hybridization with the metal substrate are observed for all molecules and compared with theoretical calculations. The substituents can influence the charge transport through the molecules by varying the distance between the metal substrate and the nanographene plane or providing additional electronic channels through iodo substituents. This effect can be quantified as a larger effective mass for carriers with increasing molecule-substrate distance, using tight binding. Our results address the critical coupling issue for metal contacts to devices using molecules as active layers.
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Affiliation(s)
- Xinliang Feng
- Institute of Materials Research and Engineering, 3 Research Link, 117602 Singapore
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144
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Noh TH, Chun IS, Lee YA, Ahn S, Hong J, Jung OS. Microsphere vs. Microbelt Morphology of Ionic Palladium(II) Complexes. BULLETIN OF THE CHEMICAL SOCIETY OF JAPAN 2008. [DOI: 10.1246/bcsj.81.1461] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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145
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Wei W, Ma GH, Hu G, Yu D, Mcleish T, Su ZG, Shen ZY. Preparation of Hierarchical Hollow CaCO3 Particles and the Application as Anticancer Drug Carrier. J Am Chem Soc 2008; 130:15808-10. [DOI: 10.1021/ja8039585] [Citation(s) in RCA: 389] [Impact Index Per Article: 24.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Affiliation(s)
- Wei Wei
- Institute of Process Engineering, Chinese Academy of Sciences, Beijing, 100190, PR China, Unilever Research China, Shanghai, 200233, PR China, Garvan Institute of Medical Research, Sydney, 2010, Australia, and School of Physics and Astronomy, Leeds University, LS2 9JT, U.K
| | - Guang-Hui Ma
- Institute of Process Engineering, Chinese Academy of Sciences, Beijing, 100190, PR China, Unilever Research China, Shanghai, 200233, PR China, Garvan Institute of Medical Research, Sydney, 2010, Australia, and School of Physics and Astronomy, Leeds University, LS2 9JT, U.K
| | - Gang Hu
- Institute of Process Engineering, Chinese Academy of Sciences, Beijing, 100190, PR China, Unilever Research China, Shanghai, 200233, PR China, Garvan Institute of Medical Research, Sydney, 2010, Australia, and School of Physics and Astronomy, Leeds University, LS2 9JT, U.K
| | - Di Yu
- Institute of Process Engineering, Chinese Academy of Sciences, Beijing, 100190, PR China, Unilever Research China, Shanghai, 200233, PR China, Garvan Institute of Medical Research, Sydney, 2010, Australia, and School of Physics and Astronomy, Leeds University, LS2 9JT, U.K
| | - Tom Mcleish
- Institute of Process Engineering, Chinese Academy of Sciences, Beijing, 100190, PR China, Unilever Research China, Shanghai, 200233, PR China, Garvan Institute of Medical Research, Sydney, 2010, Australia, and School of Physics and Astronomy, Leeds University, LS2 9JT, U.K
| | - Zhi-Guo Su
- Institute of Process Engineering, Chinese Academy of Sciences, Beijing, 100190, PR China, Unilever Research China, Shanghai, 200233, PR China, Garvan Institute of Medical Research, Sydney, 2010, Australia, and School of Physics and Astronomy, Leeds University, LS2 9JT, U.K
| | - Zhe-Yu Shen
- Institute of Process Engineering, Chinese Academy of Sciences, Beijing, 100190, PR China, Unilever Research China, Shanghai, 200233, PR China, Garvan Institute of Medical Research, Sydney, 2010, Australia, and School of Physics and Astronomy, Leeds University, LS2 9JT, U.K
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146
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Chandrasekhar N. Ballistic emission microscopy studies on metal-molecule interfaces. JOURNAL OF PHYSICS. CONDENSED MATTER : AN INSTITUTE OF PHYSICS JOURNAL 2008; 20:374113. [PMID: 21694420 DOI: 10.1088/0953-8984/20/37/374113] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
Ballistic electron emission microscopy (BEEM) experiments on metal-molecule interfaces are briefly reviewed. Results of BEEM experiments with two different orientations of molecules are presented and discussed. Significant differences in uniformity of transport through the molecular layer are found. Implications for device applications are briefly discussed.
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Affiliation(s)
- N Chandrasekhar
- Institute of Materials Research and Engineering, 3 Research Link, 117602, Singapore
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147
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Abstract
The thermodynamic principle of cooperativity is used to drive the formation of specific macromolecular complexes during the assembly of a macromolecular machine. Understanding cooperativity provides insight into the mechanisms that govern assembly and disassembly of multicomponent complexes. Our understanding of assembly mechanisms is lagging considerably behind our understanding of the structure and function of these complexes. A significant challenge remains in tackling the thermodynamics and kinetics of the intermolecular interactions required for all cellular functions.
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148
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Zhu Y, Li J, Wan M, Jiang L. 3D-boxlike polyaniline microstructures with super-hydrophobic and high-crystalline properties. POLYMER 2008. [DOI: 10.1016/j.polymer.2008.06.027] [Citation(s) in RCA: 54] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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149
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Chung SE, Park W, Shin S, Lee SA, Kwon S. Guided and fluidic self-assembly of microstructures using railed microfluidic channels. NATURE MATERIALS 2008; 7:581-7. [PMID: 18552850 DOI: 10.1038/nmat2208] [Citation(s) in RCA: 186] [Impact Index Per Article: 11.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/15/2007] [Accepted: 05/14/2008] [Indexed: 05/10/2023]
Abstract
Fluidic self-assembly is a promising pathway for parallel fabrication of devices made up of many small components. Here, we introduce 'railed microfluidics' as an agile method to guide and assemble microstructures inside fluidic channels. The guided movement of microstructures in microfluidic channels was achieved by fabricating grooves ('rails') on the top surface of the channels and also creating complementary polymeric microstructures that fit with the grooves. Using the rails as a guiding mechanism, we built complex one- and two-dimensional microsystems in which all the microstructures initially involved in the fabrication method were incorporated as components in the final product. Complex structures composed of more than 50 microstructures (each sized smaller than 50 microm) were fluidically self-assembled with zero error. Furthermore, we were able to use the rails to guide microstructures through different fluid solutions, successfully overcoming strong interfacial tension between solutions. On the basis of rail-guided self-assembly and cross-solution movement, we demonstrated heterogeneous fluidic self-assembly of polymeric microstructures and living cells. In addition to such assembly of in situ polymerized structures, we also guided and assembled externally fabricated silicon chips-demonstrating the feasible application of railed microfluidics to other materials systems.
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Affiliation(s)
- Su Eun Chung
- School of Electrical Engineering and Computer Science #066, Seoul National University, San 56-1, Shillim-dong, Kwanak-ku, Seoul 151- 744, South Korea
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150
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Facile Size-control and Fabrication of Spherical Morphology Based on Amphiphilic Ionic Platinum(II) Complexes. B KOREAN CHEM SOC 2008. [DOI: 10.5012/bkcs.2008.29.6.1266] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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