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Wang J, Wei MT, Ou-Yang HD. Low-frequency dielectrophoretic response of a single particle in aqueous suspensions. BIOMICROFLUIDICS 2016; 10:014108. [PMID: 26858820 PMCID: PMC4714981 DOI: 10.1063/1.4940037] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/10/2015] [Accepted: 01/04/2016] [Indexed: 06/05/2023]
Abstract
We use optical tweezers-based dielectrophoresis (DEP) force spectroscopy to investigate the roles of the electrical double layer in the AC dielectric response of an individual colloidal particle in an aqueous medium. Specifically, we measure the DEP crossover frequency as a function of particles size, medium viscosity, and temperature. Experimental results were compared to low frequency relaxation mechanisms predicted by Schwarz, demonstrating the dielectrophoretic responses in the frequency range between 10 kHz and 1 MHz were dominated by counterion diffusion within the electric double layer.
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Affiliation(s)
- Jingyu Wang
- Department of Physics, Lehigh University , Bethlehem, Pennsylvania 18015, USA
| | - Ming-Tzo Wei
- Bioengineering Program, Lehigh University , Bethlehem, Pennsylvania 18015, USA
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2
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Wang Y, Cheng X, Chang HC. Celebrating singularities: Mathematics and chemical engineering. AIChE J 2013. [DOI: 10.1002/aic.14123] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Affiliation(s)
- Yunshan Wang
- Dept. of Chemical and Biomolecular Engineering; University of Notre Dame; Notre Dame; IN; 46556
| | - Xinguang Cheng
- Dept. of Chemical and Biomolecular Engineering; University of Notre Dame; Notre Dame; IN; 46556
| | - Hsueh-Chia Chang
- Dept. of Chemical and Biomolecular Engineering; University of Notre Dame; Notre Dame; IN; 46556
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Wang H, Silva A, Ho CM. When Medicine Meets Engineering-Paradigm Shifts in Diagnostics and Therapeutics. Diagnostics (Basel) 2013; 3:126-54. [PMID: 26835672 PMCID: PMC4665584 DOI: 10.3390/diagnostics3010126] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2012] [Revised: 01/10/2013] [Accepted: 01/23/2013] [Indexed: 01/09/2023] Open
Abstract
During the last two decades, the manufacturing techniques of microfluidics-based devices have been phenomenally advanced, offering unlimited potential for bio-medical technologies. However, the direct applications of these technologies toward diagnostics and therapeutics are still far from maturity. The present challenges lay at the interfaces between the engineering systems and the biocomplex systems. A precisely designed engineering system with narrow dynamic range is hard to seamlessly integrate with the adaptive biological system in order to achieve the design goals. These differences remain as the roadblock between two fundamentally non-compatible systems. This paper will not extensively review the existing microfluidic sensors and actuators; rather, we will discuss the sources of the gaps for integration. We will also introduce system interface technologies for bridging the differences to lead toward paradigm shifts in diagnostics and therapeutics.
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Affiliation(s)
- Hann Wang
- Department of Mechanical and Aerospace Engineering, University of California, Los Angeles, Los Angeles, CA 90095, USA
| | - Aleidy Silva
- Department of Mechanical and Aerospace Engineering, University of California, Los Angeles, Los Angeles, CA 90095, USA
| | - Chih-Ming Ho
- Department of Mechanical and Aerospace Engineering, University of California, Los Angeles, Los Angeles, CA 90095, USA.
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4
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Sano N, Matsukura B, Ikeyama Y, Tamon H. Dielectrophoretic particle separator using mesh stacked electrodes and simplified model for multistage separation. Chem Eng Sci 2012. [DOI: 10.1016/j.ces.2012.08.034] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
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5
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Roda A, Mirasoli M, Roda B, Bonvicini F, Colliva C, Reschiglian P. Recent developments in rapid multiplexed bioanalytical methods for foodborne pathogenic bacteria detection. Mikrochim Acta 2012. [DOI: 10.1007/s00604-012-0824-3] [Citation(s) in RCA: 65] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
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Jokerst JV, Chou J, Camp JP, Wong J, Lennart A, Pollard AA, Floriano PN, Christodoulides N, Simmons GW, Zhou Y, Ali MF, McDevitt JT. Location of biomarkers and reagents within agarose beads of a programmable bio-nano-chip. SMALL (WEINHEIM AN DER BERGSTRASSE, GERMANY) 2011; 7:613-24. [PMID: 21290601 PMCID: PMC3397282 DOI: 10.1002/smll.201002089] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/20/2010] [Indexed: 05/22/2023]
Abstract
The slow development of cost-effective medical microdevices with strong analytical performance characteristics is due to a lack of selective and efficient analyte capture and signaling. The recently developed programmable bio-nano-chip (PBNC) is a flexible detection device with analytical behavior rivaling established macroscopic methods. The PBNC system employs ≈300 μm-diameter bead sensors composed of agarose "nanonets" that populate a microelectromechanical support structure with integrated microfluidic elements. The beads are an efficient and selective protein-capture medium suitable for the analysis of complex fluid samples. Microscopy and computational studies probe the 3D interior of the beads. The relative contributions that the capture and detection of moieties, analyte size, and bead porosity make to signal distribution and intensity are reported. Agarose pore sizes ranging from 45 to 620 nm are examined and those near 140 nm provide optimal transport characteristics for rapid (<15 min) tests. The system exhibits efficient (99.5%) detection of bead-bound analyte along with low (≈2%) nonspecific immobilization of the detection probe for carcinoembryonic antigen assay. Furthermore, the role analyte dimensions play in signal distribution is explored, and enhanced methods for assay building that consider the unique features of biomarker size are offered.
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Affiliation(s)
- Jesse V. Jokerst
- Departments of Chemistry and Biochemistry, University of Texas at Austin, Austin, TX 78712, USA
| | - Jie Chou
- Departments of Bioengineering and Chemistry, Rice University, 6500 Main Street, Houston, TX 77030, USA
| | - James P. Camp
- Departments of Chemistry and Biochemistry, University of Texas at Austin, Austin, TX 78712, USA
| | - Jorge Wong
- Departments of Chemistry and Biochemistry, University of Texas at Austin, Austin, TX 78712, USA
| | - Alexis Lennart
- Departments of Chemistry and Biochemistry, University of Texas at Austin, Austin, TX 78712, USA
| | - Amanda A. Pollard
- Departments of Chemistry and Biochemistry, University of Texas at Austin, Austin, TX 78712, USA
| | - Pierre N. Floriano
- Departments of Bioengineering and Chemistry, Rice University, 6500 Main Street, Houston, TX 77030, USA
| | - Nicolaos Christodoulides
- Departments of Bioengineering and Chemistry, Rice University, 6500 Main Street, Houston, TX 77030, USA
| | - Glennon W. Simmons
- Departments of Bioengineering and Chemistry, Rice University, 6500 Main Street, Houston, TX 77030, USA
| | - Yanjie Zhou
- Departments of Chemistry and Biochemistry, University of Texas at Austin, Austin, TX 78712, USA
| | - Mehnaaz F. Ali
- Departments of Chemistry and Biochemistry, University of Texas at Austin, Austin, TX 78712, USA
| | - John T. McDevitt
- Departments of Bioengineering and Chemistry, Rice University, 6500 Main Street, Houston, TX 77030, USA
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Yeo LY, Chang HC, Chan PPY, Friend JR. Microfluidic devices for bioapplications. SMALL (WEINHEIM AN DER BERGSTRASSE, GERMANY) 2011; 7:12-48. [PMID: 21072867 DOI: 10.1002/smll.201000946] [Citation(s) in RCA: 299] [Impact Index Per Article: 23.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/18/2023]
Abstract
Harnessing the ability to precisely and reproducibly actuate fluids and manipulate bioparticles such as DNA, cells, and molecules at the microscale, microfluidics is a powerful tool that is currently revolutionizing chemical and biological analysis by replicating laboratory bench-top technology on a miniature chip-scale device, thus allowing assays to be carried out at a fraction of the time and cost while affording portability and field-use capability. Emerging from a decade of research and development in microfluidic technology are a wide range of promising laboratory and consumer biotechnological applications from microscale genetic and proteomic analysis kits, cell culture and manipulation platforms, biosensors, and pathogen detection systems to point-of-care diagnostic devices, high-throughput combinatorial drug screening platforms, schemes for targeted drug delivery and advanced therapeutics, and novel biomaterials synthesis for tissue engineering. The developments associated with these technological advances along with their respective applications to date are reviewed from a broad perspective and possible future directions that could arise from the current state of the art are discussed.
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Affiliation(s)
- Leslie Y Yeo
- Micro/Nanophysics Research Laboratory, Department of Mechanical & Aerospace Engineering, Monash University, Clayton, VIC 3800, Australia
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He X, Xuan F, Wang K, Yuan Y, Cheng X. Chemical-modification-enhanced dielectrophoretic assembly of controllable and reversible silica submicrowires from nanoparticles. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2010; 26:15155-60. [PMID: 20726610 DOI: 10.1021/la1019636] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/02/2023]
Abstract
In this article, the dielectrophoretic (DEP) assembly of chemically-modified silica nanoparticles (SiNPs) was introduced. Five types of surface-modified SiNPs, including OH-SiNPs, COOH-SiNPs, CH(3)HPO(2)-SiNPs, PEG-SiNPs, and NH(2)-SiNPs, have been investigated. After applying an ac field with relatively high intensity and frequency, it was shown that only COOH-SiNPs and CH(3)HPO(2)-SiNPs could be self-assembled on the microelectrodes by the DEP forces. The results indicated that the anionic group modification could obviously enhance the DEP self-assembly of SiNPs on the microelectrodes. Then the DEP assembly of CH(3)HPO(2)-SiNPs was selected as a representative to be investigated further. By using Rubpy dye doped in the core of the CH(3)HPO(2)-SiNPs, the assembly process was visualized in real time by inverse fluorescence microscopy. Precise control over the frequency of the applied ac field showed that the DEP forces can assemble CH(3)HPO(2)-SiNPs from aqueous suspensions into submicrowires, and it was found that the number of assembled submicrowires between the microelectrode gaps could be well controlled with reversibility. Furthermore, the DEP assembly process of CH(3)HPO(2)-SiNPs was sensitive to the pH of the dispersed medium. These findings would provide a way to circumvent the difficulty in controlling the dielectrophoretic assembly process of nanoparticles and offer application opportunities for the DEP assembly of chemically modified SiNPs.
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Affiliation(s)
- Xiaoxiao He
- State Key Laboratory of Chemo/Biosensing and Chemometrics, College of Chemistry & Chemical Engineering, Hunan University, Changsha 410082, China
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Yossifon G, Chang HC. Changing nanoslot ion flux with a dynamic nanocolloid ion-selective filter: secondary overlimiting currents due to nanocolloid-nanoslot interaction. PHYSICAL REVIEW. E, STATISTICAL, NONLINEAR, AND SOFT MATTER PHYSICS 2010; 81:066317. [PMID: 20866532 DOI: 10.1103/physreve.81.066317] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/20/2010] [Revised: 05/13/2010] [Indexed: 05/10/2023]
Abstract
Nanocolloids trapped at the depleted side (anodic) of a fluidic nanoslot entrance are shown to sensitively regulate dc ion transport through the nanoslot, such that a second limiting-overlimiting transition occurs in its nonlinear current-voltage characteristics. The nanocolloids, brought to the entrance by electro-osmosis, are not stationary but are confined to closed circular and toroidal streamlines, driven by a back-pressure corner vortex and an orthogonal electroconvection vortex instability. The transition from the corner vortex to a complex torus with both vortical motions coincides with the first overlimiting transition, while electrostatic interaction of nanocolloids in these vortices with the nanoslot entrance drives the second limiting transition.
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Affiliation(s)
- Gilad Yossifon
- Faculty of Mechanical Engineering, Micro- and Nanofluidics Laboratory, Technion-Israel Institute of Technology, Technion City 32000, Israel
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Basuray S, Chang HC. Designing a sensitive and quantifiable nanocolloid assay with dielectrophoretic crossover frequencies. BIOMICROFLUIDICS 2010; 4:13205. [PMID: 20644668 PMCID: PMC2905265 DOI: 10.1063/1.3294575] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/23/2009] [Accepted: 12/28/2009] [Indexed: 05/11/2023]
Abstract
Dielectrophoretic nanocolloid assay is a promising technique for sensitive molecular detection and identification, as target molecule hybridization onto the probe-functionalized nanocolloids can change their surface conductance and consequently their dielectrophoretic crossover frequencies. Thus, instead of relying on surface charge density increase after hybridization, as in many capacitive and field effect transistor impedance sensing techniques, the current assay utilizes the much larger surface conductance (and dielectrophoresis crossover frequency) changes to effect sensitive detection. Herein, we present a Poisson-Boltzmann theory for surfaces with finite-size molecular probes that include the surface probe conformation, their contribution to surface charge with a proper delineation of the slip and Stern planes. The theory shows that the most sensitive nanocolloid molecular sensor corresponds to a minimum in the dielectrophoretic crossover frequency with respect to the bulk concentration of the molecular probes (oligonucleotides in our case) during nanocolloid functionalization. This minimum yields the lowest number of functionalized probes that are also fully stretched because of surface probe-probe interaction. Our theory provides the surface-bulk oligonucleotide concentration isotherm and a folding number for the surface oligonucleotide conformation from the crossover frequency, the zeta potential, and the hydrodynamic radius data.
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Affiliation(s)
- Sagnik Basuray
- Department of Chemical and Biomolecular Engineering, University of Notre Dame, Notre Dame, Indiana 46556, USA
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12
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Cheng X, Basuray S, Senapati S, Chang HC. Identification and separation of DNA-hybridized nanocolloids by Taylor cone harmonics. Electrophoresis 2009; 30:3236-41. [DOI: 10.1002/elps.200900159] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
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13
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Basuray S, Senapati S, Aijian A, Mahon AR, Chang HC. Shear and AC Field Enhanced Carbon Nanotube Impedance Assay for Rapid, Sensitive, and Mismatch-Discriminating DNA Hybridization. ACS NANO 2009; 3:1823-30. [PMID: 19583249 DOI: 10.1021/nn9004632] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/07/2023]
Abstract
Other than concentrating the target molecules at the sensor location, we demonstrate two distinct new advantages of an open-flow impedance-sensing platform for DNA hybridization on carbon nanotube (CNT) surface in the presence of a high-frequency AC electric field. The shear-enhanced DNA and ion transport rate to the CNT surface decouples the parasitic double-layer AC impedance signal from the charge-transfer signal due to DNA hybridization. The flow field at high AC frequency also amplifies the charge-transfer rate across the hybridized CNT and provides shear-enhanced discrimination between DNA from targeted species and a closely related congeneric species with three nucleotide mismatches out of 26 bases in a targeted attachment region. This allows sensitive detection of hybridization events in less than 20 min with picomolar target DNA concentrations in a label-free CNT-based microfluidic detection platform.
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Mairhofer J, Roppert K, Ertl P. Microfluidic systems for pathogen sensing: a review. SENSORS 2009; 9:4804-23. [PMID: 22408555 PMCID: PMC3291940 DOI: 10.3390/s90604804] [Citation(s) in RCA: 146] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/28/2009] [Revised: 06/04/2009] [Accepted: 06/08/2009] [Indexed: 01/21/2023]
Abstract
Rapid pathogen sensing remains a pressing issue today since conventional identification methodsare tedious, cost intensive and time consuming, typically requiring from 48 to 72 h. In turn, chip based technologies, such as microarrays and microfluidic biochips, offer real alternatives capable of filling this technological gap. In particular microfluidic biochips make the development of fast, sensitive and portable diagnostic tools possible, thus promising rapid and accurate detection of a variety of pathogens. This paper will provide a broad overview of the novel achievements in the field of pathogen sensing by focusing on methods and devices that compliment microfluidics.
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Affiliation(s)
- Jürgen Mairhofer
- Department of Biotechnology, University of Natural Resources and Applied Life Sciences, Muthgasse 18, 1190 Vienna, Austria
| | - Kriemhilt Roppert
- Division of Nano-System-Technologies, Austrian Research Centers GmbH – ARC, Donau-City-Street 1, 1220 Vienna, Austria
| | - Peter Ertl
- Division of Nano-System-Technologies, Austrian Research Centers GmbH – ARC, Donau-City-Street 1, 1220 Vienna, Austria
- Author to whom correspondence should be addressed; E-Mail: ; Tel.: +43-(0)50550-4305; Fax: +43-(0)50550-4399
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Froude VE, Zhu Y. Dielectrophoresis of Functionalized Lipid Unilamellar Vesicles (Liposomes) with Contrasting Surface Constructs. J Phys Chem B 2009; 113:1552-8. [DOI: 10.1021/jp808454w] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Victoria E. Froude
- Department of Chemical and Biomolecular Engineering, University of Notre Dame, Notre Dame, Indiana 46556
| | - Yingxi Zhu
- Department of Chemical and Biomolecular Engineering, University of Notre Dame, Notre Dame, Indiana 46556
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Chang HC, Yossifon G. Understanding electrokinetics at the nanoscale: A perspective. BIOMICROFLUIDICS 2009; 3:12001. [PMID: 19693382 PMCID: PMC2717603 DOI: 10.1063/1.3056045] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/30/2008] [Accepted: 12/02/2008] [Indexed: 05/02/2023]
Abstract
Electrokinetics promises to be the microfluidic technique of choice for portable diagnostic chips and for nanofluidic molecular detectors. However, despite two centuries of research, our understanding of ion transport and electro-osmotic flow in and near nanoporous membranes, whose pores are natural nanochannels, remains woefully inadequate. This short exposition reviews the various ion-flux and hydrodynamic anomalies and speculates on their potential applications, particularly in the area of molecular sensing. In the process, we revisit several old disciplines, with some unsolved open questions, and we hope to create a new one.
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Affiliation(s)
- Hsueh-Chia Chang
- Department of Chemical and Biomolecular Engineering, Center for Microfluidics and Medical Diagnostics, University of Notre Dame, Notre Dame, Indiana 46556, USA
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Hoffman PD, Sarangapani PS, Zhu Y. Dielectrophoresis and AC-induced assembly in binary colloidal suspensions. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2008; 24:12164-71. [PMID: 18842062 DOI: 10.1021/la8013392] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/11/2023]
Abstract
Dielectrophoretic behaviors and assembly of a binary suspension in aqueous media are examined in the presence of nonuniform alternating current (AC) electric field. A peculiar low-frequency threshold and dielectrophoresis (DEP) crossover frequency determine the applicable frequency window for binary assembly under positive DEP, which can be effectively tuned by medium conductivity and particle size, suggesting that the dynamic double-layer effect is responsible for the interfacial polarization of micrometer to submicrometer-sized particles in aqueous suspensions. Strong effects of AC-field frequency, medium conductivity, and size ratio on binary assembly morphology have been observed. A frequency-medium conductivity phase diagram is obtained to illustrate the morphological transition of assembled colloidal aggregates from segregated, ordered assemblies to inverted segregation with the appearance of amorphous phases upon increasing frequency and/or medium conductivity, which is a direct consequence of the competition between DEP and hydrodynamic mobility. Significantly, our results demonstrate a rapid method to form hybrid nanostructured materials.
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Affiliation(s)
- Peter D Hoffman
- Department of Chemical and Biomolecular Engineering, University of Notre Dame, IN 46556, USA
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Minerick AR. The rapidly growing field of micro and nanotechnology to measure living cells. AIChE J 2008. [DOI: 10.1002/aic.11615] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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Wang SC, Wei HH, Chen HP, Tsai MH, Yu CC, Chang HC. Dynamic superconcentration at critical-point double-layer gates of conducting nanoporous granules due to asymmetric tangential fluxes. BIOMICROFLUIDICS 2008; 2:14102. [PMID: 19693364 PMCID: PMC2716920 DOI: 10.1063/1.2904640] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/21/2008] [Accepted: 03/07/2008] [Indexed: 05/25/2023]
Abstract
A transient 10(6)-fold concentration of double-layer counterions by a high-intensity electric field is demonstrated at the exit pole of a millimeter-sized conducting nanoporous granule that permits ion permeation. The phenomenon is attributed to a unique counterion screening dynamics that transforms half of the surface field into a converging one toward the ejecting pole. The resulting surface conduction flux then funnels a large upstream electro-osmotic convective counterion flux into the injecting hemisphere toward the zero-dimensional gate of the ejecting hemisphere to produce the superconcentration. As the concentrated counterion is ejected into the electroneutral bulk electrolyte, it attracts co-ions and produce a corresponding concentration of the co-ions. This mechanism is also shown to trap and concentrate co-ion microcolloids of micron sizes too (macroions) and hence has potential application in bead-based molecular assays.
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