Bacterial handling under the influence of non-uniform electric fields: dielectrophoretic and electrohydrodynamic effects

This paper describes the modeling and experimental verification of a castellated microelectrode array intended tohandle biocells, based on common dielectrophoresis. The proposed microsystem was developed employing platinumelectrodes deposited by lift-off, silicon micromachining, and photoresin patterning techniques. Having fabricated the microdevice it was tested employing Escherichia coli as bioparticle model. Positive dielectrophoresis could be verified with the selected cells for frequencies above 100 kHz, and electrohydrodynamic effects were observed as the dominant phenomena when working at lower frequencies. As a result, negative dielectrophoresis could not be observed because its occurrence overlaps with electrohydrodynamic effects; i.e. the viscous drag force acting on the particles is greater than the dielectrophoretic force at frequencies where negative dielectrophoresis should occur. The experiments illustrate the convenience of this kind of microdevices to micro handling biological objects, opening the possibility for using these microarrays with other bioparticles. Additionally, liquid motion as a result of electrohydrodynamic effects must be taken into account when designing bioparticle micromanipulators, and could be used as mechanism to clean the electrode surfaces, that is one of the most important problems related to this kind of devices.

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Electrokinetic Formation of “Microbridges” for Protein Biomarkers as Sensors

JALA Journal of the Association for Laboratory Automation ◽

10.1016/j.jala.2007.06.001 ◽

2007 ◽

Vol 12 (5) ◽

pp. 311-317 ◽

Cited By ~ 2

Author(s):

Vindhya Kunduru ◽

Shalini Prasad

Keyword(s):

Electric Fields ◽

Microelectrode Array ◽

Protein Detection ◽

High Specificity ◽

Detection Methods ◽

Label Free ◽

Protein Biomarkers ◽

Detection Scheme ◽

Polystyrene Beads ◽

Conducting Path

We demonstrate a technique to detect protein biomarkers contained in vulnerable coronary plaque using a platform-based microelectrode array (MEA). The detection scheme is based on the property of high specificity binding between antibody and antigen similar to most immunoassay techniques. Rapid clinical diagnosis can be achieved by detecting the amount of protein in blood by analyzing the protein's electrical signature. Polystyrene beads which act as transportation agents for the immobile proteins (antigen) are electrically aligned by application of homogenous electric fields. The principle of electrophoresis is used to produce calculated electrokinetic movement among the anti-C-reactive protein (CRP), or in other words antibody funtionalized polystyrene beads. The electrophoretic movement of antibody-functionalized polystyrene beads results in the formation of “Microbridges” between the two electrodes of interest which aid in the amplification of the antigen—antibody binding event. Sensitive electrical equipment is used for capturing the amplified signal from the “Microbridge” which essentially behaves as a conducting path between the two electrodes. The technique circumvents the disadvantages of conventional protein detection methods by being rapid, noninvasive, label-free, repeatable, and inexpensive. The same principle of detection can be applied for any receptor—ligand-based system because the technique is based only on the volume of the analyte of interest. Detection of the inflammatory coronary disease biomarker CRP is achieved at concentration levels spanning over the lower microgram/milliliter to higher order nanogram/milliliter ranges.

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Measurement of electric fields at electrode surfaces

Electronics Letters ◽

10.1049/el:19650102 ◽

1965 ◽

Vol 1 (4) ◽

pp. 110 ◽

Cited By ~ 17

Author(s):

J.M. Meek ◽

M.M.C. Collins

Keyword(s):

Electric Fields ◽

Electrode Surfaces

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Inhomogeneity of Interfacial Electric Fields at Vibrational Probes on Electrode Surfaces

ACS Central Science ◽

10.1021/acscentsci.9b01297 ◽

2020 ◽

Vol 6 (2) ◽

pp. 304-311 ◽

Cited By ~ 6

Author(s):

Zachary K. Goldsmith ◽

Maxim Secor ◽

Sharon Hammes-Schiffer

Keyword(s):

Electric Fields ◽

Electrode Surfaces

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The numerical study of viscous drag force influence on low-frequency surge motion of a semi-submersible in storm sea states

Ocean Engineering ◽

10.1016/j.oceaneng.2020.107511 ◽

2020 ◽

Vol 213 ◽

pp. 107511 ◽

Cited By ~ 1

Author(s):

Shan Ma ◽

De-kang Xu ◽

Wen-yang Duan ◽

Ji-kang Chen ◽

Kang-ping Liao ◽

...

Keyword(s):

Drag Force ◽

Numerical Study ◽

Low Frequency ◽

Viscous Drag ◽

Viscous Drag Force

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Characterization of Simple and Double Yeast Cells Using Dielectrophoretic Force Measurement

Sensors ◽

10.3390/s19173813 ◽

2019 ◽

Vol 19 (17) ◽

pp. 3813 ◽

Cited By ~ 3

Author(s):

Fernando-Juan García-Diego ◽

Mario Rubio-Chavarría ◽

Pedro Beltrán ◽

Francisco J. Espinós

Keyword(s):

Electric Fields ◽

Force Measurement ◽

Point Of View ◽

Yeast Cells ◽

Instrumental Method ◽

Particle Characterization ◽

Dielectrophoretic Force ◽

Cell Velocity ◽

First Time

Dielectrophoretic force is an electric force experienced by particles subjected to non-uniform electric fields. In recent years, plenty of dielectrophoretic force (DEP) applications have been developed. Most of these works have been centered on particle positioning and manipulation. DEP particle characterization has been left in the background. Likewise, these characterizations have studied the electric properties of particles from a qualitative point of view. This article focuses on the quantitative measurement of cells’ dielectric force, specifically yeast cells. The measures are obtained as the results of a theoretical model and an instrumental method, both of which are developed and described in the present article, based on a dielectrophoretic chamber made of two V-shaped placed electrodes. In this study, 845 cells were measured. For each one, six speeds were taken at different points in its trajectory. Furthermore, the chamber design is repeatable, and this was the first time that measurements of dielectrophoretic force and cell velocity for double yeast cells were accomplished. To validate the results obtained in the present research, the results have been compared with the dielectric properties of yeast cells collected in the pre-existing literature.

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Self and Directed Colloidal Assembly on Patterned Electrodes

Fluids Engineering ◽

10.1115/imece2005-80628 ◽

2005 ◽

Author(s):

P. Bahukudumbi ◽

Michael A. Bevan ◽

Ali Beskok

Keyword(s):

Electric Fields ◽

Colloidal Particles ◽

Colloidal Particle ◽

Three Dimensional ◽

Directed Assembly ◽

Ordered Structures ◽

Colloidal Assembly ◽

Electrode Surfaces ◽

External Electric Fields ◽

Potential Energy Landscapes

Clustering of colloidal particles near an electrode surface during and after electrophoretic deposition has been reported in the literature [1, 2, 3, 4]. The aggregation of colloidal particles has made the precise assembly of two and three dimensional colloidal crystals possible. In this paper, we demonstrate the use of external electric fields to sensitively tune the interactions between colloidal particles to form ordered structures. The directed assembly of colloidal particles on patterned electrode surfaces is also investigated as a means of building three-dimensional nanostructures. Finally, a new method to map potential energy landscapes of templated substrates using a diffusing colloidal particle as a sensitive local energy probe is described.

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Manipulation of Organic and Inorganic Colloidal Particles by Dielectrophoretic Forces

Volume 11: Micro and Nano Systems, Parts A and B ◽

10.1115/imece2007-44093 ◽

2007 ◽

Author(s):

Ramazan Asmatulu ◽

Dennis Siginer

Keyword(s):

Liquid Medium ◽

Electric Fields ◽

Colloidal Particles ◽

Dielectrophoretic Force ◽

Inorganic Particles ◽

Ac Electric Fields ◽

The Creation ◽

Manipulation Process

Recently, manipulation of the micro and nanoscale objects has been of great interest in verity of engineering and scientific areas. Dielectrophoretic force (DEP) induced technique is predominantly used in the manipulation process in a liquid medium. The phenomenon behind DEP involves the creation of electric forces on particles to generate momentum in nonuniform electric fields, usually coming from AC electric fields. In the present study, we will discuss about the effects of DEP for the manipulation of organic and inorganic particles at micro and nanoscale in detail.

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Electric Field-Assisted Positioning of Neurons on Pt Microelectrode Arrays

MRS Proceedings ◽

10.1557/proc-773-n4.6 ◽

2003 ◽

Vol 773 ◽

Author(s):

Shalini Prasad ◽

Mo Yang ◽

Xuan Zhang ◽

Yingchun Ni ◽

Vladimir Parpura ◽

...

Keyword(s):

Electric Field ◽

Electrical Activity ◽

Electric Fields ◽

Microelectrode Array ◽

Electrode Array ◽

Sprague Dawley ◽

A Cell ◽

Neuron Patterning

AbstractCharacterization of electrical activity of individual neurons is the fundamental step in understanding the functioning of the nervous system. Single cell electrical activity at various stages of cell development is essential to accurately determine in in-vivo conditions the position of a cell based on the procured electrical activity. Understanding memory formation and development translates to changes in the electrical activity of individual neurons. Hence, there is an enormous need to develop novel ways for isolating and positioning individual neurons over single recording sites. To this end, we used a 3x3 multiple microelectrode array system to spatially arrange neurons by applying a gradient AC field. We characterized the electric field distribution inside our test platform by using two dimensiona l finite element modeling (FEM) and determined the location of neurons over the electrode array. Dielectrophoretic AC fields were utilized to separate the neurons from the glial cells and to position the neurons over the electrodes. The neurons were obtained from 0-2-day-old rat (Sprague-Dawley) pups. The technique of using electric fields to achieve single neuron patterning has implications in neural engineering, elucidating a new and simpler method to develop and study neuronal activity as compared to conventional microelectrode array techniques.

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Magnetic manipulation on the unlabeled nonmagnetic particles

International Journal of Modern Physics B ◽

10.1142/s0217979219500474 ◽

2019 ◽

Vol 33 (07) ◽

pp. 1950047 ◽

Cited By ~ 1

Author(s):

Yongqing He ◽

Laan Luo ◽

Shuang Huang

Keyword(s):

Flow Rate ◽

Magnetic Force ◽

Opposite Polarity ◽

Viscous Drag ◽

Maximum Deviation ◽

Magnetic Manipulation ◽

Practical Applications ◽

Viscous Drag Force ◽

Flow Rate Range ◽

Nonmagnetic Particles

This paper reports two basic microfluidic strategies for the magnetic manipulation of unlabeled nonmagnetic particles/cells. One is the deflection induced by a single magnet, and the other is the confusing effect produced by two magnets of opposite polarity. They can be combined into more completed particle manipulations like continuous flow separation, counting and detection, which are essential steps in biomedical applications. We experimentally studied the dynamics of 10.4 and 20 [Formula: see text]m nonmagnetic polystyrene particles within a flow rate range of 30, 50, 70 and 90 [Formula: see text]L/min in a straight channel. We defined the cross-section length that the particles occupy as the “particle bandwidth” to characterize the extent of deflection and focusing. To predict the trajectories of the particles, we established a simple theoretical model by considering the magnetic force and viscous drag force. Compared with the experimental results, the maximum deviation of the simulation is 9.28%. The influences of magnetic nanoparticle concentration, magnetic field parameters, size of microparticles and flow rate are systematically investigated. We also demonstrated that the effective deflection and focusing could be realized at low Fe3O4 nanoparticle concentrations, which means that this method can reduce the damage on cells in the practical applications.

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Dynamics of photo-ablated carbon plasma in an inert gas atmosphere

Laser and Particle Beams ◽

10.1017/s0263034600011745 ◽

1998 ◽

Vol 16 (1) ◽

pp. 31-38 ◽

Cited By ~ 1

Author(s):

T. Kerdja ◽

S. Abdelli ◽

E. H. Amara ◽

D. Ghobrini ◽

M. Si-Bachir ◽

...

Keyword(s):

Wave Model ◽

Inert Atmosphere ◽

Viscous Drag ◽

Laser Evaporation ◽

Force Model ◽

Plasma Dynamics ◽

Gas Atmosphere ◽

Viscous Drag Force ◽

Swan Band ◽

Two Stages

Time and space-resolved emission spectroscopy measurements were performed to investigate plasma dynamics during laser evaporation of a graphite target in an ambient inert atmosphere. Intense molecular emission is found to occur behind a front separating the plasma from the foreign gas. Two stages of expansion are found and are well described, using a viscous drag force model for the first one and a delayed ideal blast wave model for the second. The vibrational temperature estimated using the Swan band in helium at different pressures is presented.

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