This paper reports an interesting phenomenon that the velocity increases with increasing sodium chloride (NaCl) concentration in induced charge electroosmosis (ICEO) around a conducting cylinder measured by microparticle image velocimetry (μPIV). It is different from the widely reported velocity decay with i
N-type porous silicon can be used to realize electroosmotic pumps with high flow rates per applied potential difference. The porosity and pore size of poro
A microchip integrated microfabricated, microfluidic, multichannel, preferably electroosmotic pump and pumping system is disclosed. The electroosmotic pump of the invention comprises a plurality of mi
The techniques for a dynamic and permanent reversal of the electroosmotic flow (EOF) were used for the reversal of the enantiomer migration order (EMO) of neutral and cationic analytes in chiral capillary electrophoresis (CE). Native beta-Cd and an anionic CD derivative, CM-beta-CD were used in both, bare silica- and positively coated capillaries. Advantages and disadvantages of a dynamic and permanent modification of the capillary inner surface are briefly discussed.
The hydrodynamic and thermal characteristics of electroosmotic and pressure-driven flows of power-law fluids are examined in a semicircular microchannel under the constant wall heat flux condition. For sufficiently large values of the electrokinetic radius, the Debye length is thin; the active flow within the electric double layer (EDL) drags the rest of the liquid due to frictional forces arising from the fluid viscosity, and consequently a plug-like velocity profile is attained. The velocity ratio can affect the pure electrokinetic flow as well as the flow rate depending on the applied pressure gradient direction. Since the effective viscosity of shear-thinning fluids near the wall is quite small compared to the shear-thickening fluids, the former exhibits higher dimensionless velocities than the later close to the wall; the reverse is true at the middle section. Poiseuille number increases with increasing the flow behavior index and/or the electrokinetic radius. Due to the comparatively ...
Electric fields can be used to concentrate, pattern, and sort various sized colloidal particles, droplets, and bubbles. Electrokinetic phenomena such as electrophoresis, electroosmosis, dielectrophoresis, electrothermal flows, induced charge electrokinetics, and electrohydrodynamic, are at play during these processes leading to direct or indirect manipulation of these colloidal scale objects. Fundamental and applied papers pertaining to the assembly, transport, or deformation of particles, droplets and/or bubbles using electrokinetics or related physical phenomena are welcome. Papers that include microfluidics, interfacial deformation or separations, and assembly for advanced materials are encouraged.. ...
A membrane with both high ion conductivity and selectivity is critical to high power density and low-cost flow batteries, which are of great importance for the wide application of renewable energies. The trade-off between ion selectivity and conductivity is a bottleneck of ion conductive membranes. In this paper, a thin-film composite membrane with ultrathin polyamide selective layer is found to break the trade-off between ion selectivity and conductivity, and dramatically improve the power density of a flow battery. As a result, a vanadium flow battery with a thin-film composite membrane achieves energy efficiency higher than 80% at a current density of 260 mA cm−2, which is the highest ever reported to the best of our knowledge. Combining experiments and theoretical calculation, we propose that the high performance is attributed to the proton transfer via Grotthuss mechanism and Vehicle mechanism in sub-1 nm pores of the ultrathin polyamide selective layer. Low-cost flow batteries with high power
TY - JOUR. T1 - Dentate development in organotypic hippocampal slice cultures from p35 knockout mice. AU - Wenzel, H. Jürgen. AU - Tamse, Catherine T.. AU - Schwartzkroin, Philip A. PY - 2006/12. Y1 - 2006/12. N2 - Abnormal brain development, induced by genetic influences or resulting from a perinatal trauma, has been recognized as a cause of seizure disorders. To understand how and when these structural abnormalities form, and how they are involved in epileptogenesis, it is important to generate and investigate animal models. We have studied one such model, a mouse in which deletion of the p35 gene (p35-/-) gives rise to both structural disorganization and seizure-like function. We now report that aberrant dentate development can be recognized in the organotypic hippocampal slice culture preparation generated from p35-/- mouse pups. In these p35-/- cultures, an abnormally high proportion of dentate granule cells migrates into the hilus and molecular layer, and develops aberrant dendritic and ...
An electroosmotic EO process is presented for nanoporous membranes capable of generating EO flow rates over thirty times higher than previously possible with the same membrane and solution. In...
In capillary electrophoresis systems, real-time monitoring and measurement of the electroosmotic flow through a separation capillary is accomplished by coupling the outlet of the separation capillary to an electrically-conductive junction. In one embodiment, this junction is an ion-impermeable or an ion-exchange membrane unit that preferentially exchanges ions having a charge opposite to analyte ions of interest. Within a downstream region of the junction, all axial incremental voltage from the electroosmotic voltage source is terminated, which ensures that downstream electrolyte ion movement is passive, due to active flow created upstream when an incremental axial voltage existed. Upstream electrolyte ion flux is proportional to C1 (μe +μeo), where C1 is the upstream concentration of the electrolyte ion of interest, μe is the electrolyte electrophoretic mobility, and μeo is the electroosmotic mobility. Downstream, the flux is proportional to C2 μeo, where C2 is the downstream concentration of
Thermally developing electroosmotically generated flow of two viscoelastic fluids, namely the PTT and FENE-P models, through a slit microchannel is considered. Both the viscous dissipation and Joule heating effects are taken into account and a step change in wall temperature is considered to represent physically conceivable thermal entrance conditions. Expressions for the dimensionless temperature and Nusselt number in the form of infinite series are presented. In general, the resultant eigenvalue problem is solved numerically; nevertheless, an analytical solution is presented for the regions close to the entrance. A parametric study reveals that increasing amounts of the Peclet number result in higher wall heat fluxes. The results also indicate higher wall heat fluxes for non-Newtonian fluids in comparison with Newtonian fluids and the difference is increased with increasing the level of elasticity. Furthermore, based on the value of the dimensionless Joule heating parameter, the Nusselt number ...
Research in bioelectronics studies biological systems and materials in combination with electronic interfaces for the development of devices, e.g., for medical applications, drug and toxicity tests, and biotechnology in general. Neural implants and pacemakers are examples of products developed from this area of research. Conducting polymers such as poly(3,4-ethylenedioxythiophene) (PEDOT) bridge biology and electronics with a combination of biocompatibility, flexibility, and capability to themselves undergo redox reactions. Electrokinetics, a related branch of science, describes the motion of fluids and particles caused by the application of an electric field, and includes various separation techniques such as gel electrophoresis. Applying an electric field in a sufficiently small diameter silica capillary can cause the liquid in the capillary to move. This phenomenon, referred to as electroosmosis, plays an important role in miniaturized microfluidic systems and can be used to drive flow in a ...
We have demonstrated the dexamethasone sodium phosphate (DmNaP) is delivered most efficiently from the negative electrode by iontophoresis, but, under certain conditions, the delivery from the positive electrode by electroosmosis can be accomplished. The laboratory data indicate that more dexamethasone is delivered per mA-min by iontophoresis than by electtoomosis, thus the same amount of drug can be administered in a shorter time from the negative electrode. Electrodes containing a hydrogel material, which restricts bulk water transport, delivered DmNaP most efficiently from the electrode of a negative polarity. When DmNaP is to be delivered in a mixture with another drug such as lidocaine, selection of the clinical treatment protocol depends on the desired therapeutic effect on the iontophoreic electrode which is to be used. When minimization of total treatment time is not critical, switching polarity of the electrode during the treatment can be used to administer drugs of opposite polarity ...
The BH3 interacting-domain death agonist (BID) is a pro-apoptotic protein involved in death receptor-induced and mitochondria-mediated apoptosis. Recently, it has also been suggested that BID is involved in the regulation of inflammatory responses in the central nervous system. We found that BID deficiency protected organotypic hippocampal slice cultures in vitro from neuronal injury induced by oxygen-glucose deprivation. In vivo, BID-knockout (KO) mice and WT mice were subjected to 60 minutes of transient middle cerebral artery occlusion to induce focal cerebral ischemia, and allowed to recover for 24 hours. Infarct volumes and functional outcome were assessed and the inflammatory response was evaluated using immunofluorescence, Western blotting, quantitative PCR and Mesoscale multiplex analysis. We observed no difference in the infarct volume or neurological outcome between BID-KO and WT mice. The inflammatory response was reduced by BID deficiency as indicated by a change in microglial/leukocyte
The membrane is the secret to making the whole thing both economical and durable. Most flow batteries today use flourinated membranes which are expensive - up to 20% of the total cost of a battery. Cheaper membranes simply dont stand up very long to the highly alkaline environment found inside a typical flow battery.. According to research paper published recently in the journal Joule, scientists at the Lawrence Berkeley National Lab say they have have developed a versatile yet affordable battery membrane from a class of polymers known as AquaPIMs. These polymers make inexpensive and long lasting grid batteries possible based solely on abundant materials such as zinc, iron, and water. AquaPIM membranes work with different battery chemistries, from metals and inorganics to organics and polymers, and they help create stable cells which last far longer before degrading.. The team also developed a simple computer modeling technique that shows how different battery membranes impact the life ...
Authors: YUE LIU, LI XIE, XIAOXUE FAN, DINGYAN FAN, SHASHENG HUANG Abstract: Gold nanochannels were prepared by plating electrolessly gold within the pores of polycarbonate filter membranes (PCTMs). These PCTMs with cylindrical Au nanotubules of uniform radius and high density can be used as a convenient model system to investigate the mechanism of particle transport through nanotubules. The transport properties of phenol through a modified Au nanotubule membrane were studied. The permeate flux of phenol transport through the nanotubule membrane can be spatially and temporally manipulated by controlling the magnitude and direction of the current applied across the separation cell, and the electroosmotic flow (EOF) was investigated by measuring the flux of phenol across the PCTM. The current values and modification of nanotubules affected the EOF generated inside the nanotubules. The permeation flux of phenol through the nanotubule membrane can be easily changed by modifying the Au nanotubules ...
There is a great interest to quantitatively manipulate, separate, and deliver low concentrations or even single biomolecules in submicrometer-sized channels. We report the use of cross-linked four-star polyethylene glycol (PEG) as a new coating technique for microchannels. PEG-coating efficiently reduces the electroosmotic flow (EOF) and non-specific adsorption to the glass walls. Our results demonstrate that individual fluorescently labeled hydrophobic cell adhesion proteins (fibronectin molecules) can be drawn through PEG-coated submicrometer pipettes in aqueous solution by electrokinetic forces without the addition of detergents or other additives which potentially deteriorate the activity and specificity of biomolecules. (C) 2004 Elsevier B.V. All rights reserved ...
The dimensions of microfluidic devices closely parallel those of biological cells; thusly, they are excellent platforms for the speciation, transport, manipulation, and analysis of cells. Electrokinetic transport of Escherichia coli and Saccharomyces cerevisiae was evaluated in microfluidic devices fabricated in pristine and UV-modified poly(methylmethacrylate) and polycarbonate. The magnitude and direction of transport of the cells was dictated by the buffer composition, conduit surface chemistry, and intrinsic cellular electrical properties. Bakers yeast in all devices migrated toward the cathode, because of their smaller electrophoretic mobility compared to the electroosmotic flow of the polymer. E. coli cells suspended in 20 mM PBS migrated toward the anode, which indicated that the apparent mobility of the E. coli cells changed direction at higher ionic strengths. The observed differential migrations were exploited to sort cells, whereby judicious choice of the buffer concentration and the ...
Silvia, Scarmagnani and Zarah, Walsh and Benito-Lopez, Fernando and Mirek, Macka and Paull, Brett and Diamond, Dermot (2010) Incorporation of acrylate based spiropyran monoliths in micro-fluidic devices for photo-controlled electroosmotic flow. Advances in Science and Technology, 76 . pp. 100-105. ISSN 1662-0356 ...
FSU researchers introduce new lithium (Li)-air flow batteries aimed to overcome major disadvantages of traditional Li-air batteries such as low current density and poor cyclability. The battery consists of three Units: the electrochemical (EC) reaction unit, the electrolyte storage unit, and the oxygen exchange unit which mimics the structure of a classical fuel cell system.. Traditional Li-air batteries have an extremely large theoretical energy density, but suffer from several drawbacks:. ...
More and more electricity is being generated from intermittent sources of power, such as solar and wind energy. Powerful electric energy storage devices are necessary to level out corresponding irregularities in the power supply. Fraunhofer scientists have recently made an important breakthrough with their development of a redox flow battery that reaches stack power up to 25 kW, with a cell size of 0.5 square meters. This is eight times larger than the previous A4-sized systems. They will be presenting the new battery for the first time at the Hannover Messe trade show (from April 8-12).
But what the CEO said is spot on! The power grid was created to shove energy down the line and that was about it. If the CEO of this company can see that power distribution needs to change then I can admit they can fulfill a niche and carve out a space that adds benefit to the distribution of power. I mean there is no "great battle" but more of an armistice where boarders are redrawn and resources split. Unless the Li-ion market collapses (grapheme-aluminum-oxygen battery is made in production volumes) then last gasp, no man standing, fight to the death, could be the norm. But in the upcoming decade, yes, our grid is going to change drastically. I see flow batteries at the power stations, spread out among neighborhoods, even at office buildings and hospitals. AMS can play their role too maybe sell the farm, get rich, and provide the software to load balance/shift battery power around. Who knows? But something to keep an eye on ...
A redox flow battery system is provided with one or more tanks for containing electrolytes. Embodiments of electrolyte tanks include active and/or passive dividers within a single tank structure. Dividers may be configured to prevent mixing of a charged electrolyte and a discharged electrolyte stored within a single tank.
A new business model innovation could lower the price for vanadium flow batteries, nudging them closer to competitiveness with lithium: rentable electrolytes.
The use of ambipolar redox active materials comprised of electron rich and electron poor groups (donor-acceptor strategy) is proposed to generate molecules with tuneable redox potentials. This allows their implementation on both the positive as negative half-cell of the battery, avoiding capacity loss by crossover. An iterative design strategy will be used to build a library of compounds that will be screened for reversible redox chemistry and stability. New membranes separating the half cells will be developed and matched with redox materials that passed the first screening, testing for compatibility and crossover rates. Finally, all components will be combined and studied in prototype flow batteries. Results from these studies will be used as input for computational modelling in order to predict a new generation of redox compounds and improved membrane design. This ultimately leads to a detailed understanding on their structure-property relations and development of materials that can be used ...
TY - CONF. T1 - Testing of Nickel-Cobalt-Oxide as a bifunctional catalyst in air electrodes for Zinc/Air Redox Flow Batteries. AU - Rescec, Lucas. AU - Pichler, Birgit Elvira. AU - Hacker, Viktor. PY - 2016/8/31. Y1 - 2016/8/31. M3 - Poster. ER - ...
HIGH PERFORMANCE FLOW BATTERY - High performance flow batteries, based on alkaline zinc/ferro-ferricyanide rechargeable ("ZnFe") and similar flow batteries, may include one or more of the following improvements. First, the battery design has a cell stack comprising a low resistance positive electrode in at least one positive half cell and a low resistance negative electrode in at least one negative half cell, where the positive electrode and negative electrode resistances are selected for uniform high current density across a region of the cell stack. Second, a flow of electrolyte, such as zinc species in the ZnFe battery, with a high level of mixing through at least one negative half cell in a Zn deposition region proximate a deposition surface where the electrolyte close to the deposition surface has sufficiently high zinc concentration for deposition rates on the deposition surface that sustain the uniform high current density. The mixing in the flow may be induced by structures such as: ...
An alternating current electroosmotic micro pumping device has been designed, experimentally tested and theoretically analyzed using an electrohydrodynamic theoretical model applied to a computer simulation model. The ...
BATTERY CELL STACK AND REDOX FLOW BATTERY | CELL MODULE | Method of Direct Electrochemical Oxidation For Modifying Carbon Felts of Flow Battery | TWO-LAYER COATINGS ON METAL SUBSTRATES AND DENSE ELECTROLYTE FOR HIGH SPECIFIC POWER METAL-SUPPORTED SOFC | POROUS SUPPORT, PREPARATION METHOD THEREFOR, AND REINFORCED MEMBRANE CONTAINING SAME |
An apparatus including at least one electrochemical flow cell in which the electrochemical flow cell includes an anode electrode, a cathode electrode and a reaction zone between the anode and the cath
The range of batteries, or energy storage machines, we offer have a reference showing the number of kilowatts of power output and the number of kilowatt hours of storage.. A 30/150, for example, is a flow battery with 30kW of power and 150kWh of storage with the ability to provide the 30kW for 5 hours; a 250/2000 is a flow battery with 250kW of power output and 2000kWh (2MWh) of storage with the ability to deliver 250kW of power for 8 hours.. All the batteries are scalable and can be added together in multiples to suit your requirements.. ...
A team at Massachusetts Institute of Technology has developed a type of battery which it says could store energy for long durations at a fraction of the cost of current storage technologies.
A new type of energy storage system could revolutionise energy storage and drop the charging time of electric cars from hours to seconds. In a new paper published today in the journal Nature... Read more ...
December 14, 2017 (Source) - Chesapeake Gold Corp. ("Chesapeake") (TSX-V:CKG) is pleased to provide an update of the Phase 1 drilling and […]. ...
Figure 16. Received Power Sensed. The received power can calculate by the following formula.. PRX,AC = (VRECT x IOUT) / EffRECT + Pres_loss + Poffset. PRX, AC is the Received Power for RP packet. VRECT is the output voltage of rectifier from ADC. IOUT is the output current from ADC. Eff_RECT is the efficiency of rectifier. Poffset is the initial power offset for PTX and PRX. Pres_loss = k (RS + RESR) x IOUT2. k is a constant coefficient RS is the AC resistance of Rx coil. RESR is the AC resistance of series capacitor. RS = RX100 [1 + A (f / 100 - 1) + B (f / 100 - 1)2]. RX100 is the Rx coil resistance at 100kHz. F is the AC frequency from Tx. A and B is the resistance matching coefficient RESR = RCS100 / (f / 100). RCS100 is the capacitor resistance at 100kHz. To use the GUI for the FOD calibration, the customer should measure the resistance of the coil from 100kHz to 200kHz and select the RX100, coefficient A and B to match the resister with frequency. The resister of the capacitor, RCS100, ...
Compositions and processes useful for inhibiting the transfer to fabric articles of solubilized or suspended dyes found in fabric laundering solutions. Such dyes are oxidized by a composition comprising a peroxygen compound, certain aldehydes and ketones, a zwitterionic surfactant and a buffer compound.
Professor W. Craig Carter came to MIT with a research focus in the application of theoretical and computational materials science to microstructural evolution and the relations between material properties and microstructure. He places particular emphasis on the physical analysis of complex processes when possible and the development of numerical algorithms and codes when microstructural simulation is required, and in recent years he has brought his interests and skills to the science of battery materials and the electro-chemo-mechanics of phase transitions and fracture of battery electrodes. He and Professor Yet-Ming Chiang have developed a flow battery that utilizes co-suspensions of solid state electrode and electronically conductive particulates. They co-founded a company, 24M, to produce grid scale energy storage soluntions.. Professor Carter is recognized as one of DMSEs most innovative instructors. He is a MacVicar Fellow and has received the MIT School of Engineering Bose Teaching Award. ...
Professor W. Craig Carter came to MIT with a research focus in the application of theoretical and computational materials science to microstructural evolution and the relations between material properties and microstructure. He places particular emphasis on the physical analysis of complex processes when possible and the development of numerical algorithms and codes when microstructural simulation is required, and in recent years he has brought his interests and skills to the science of battery materials and the electro-chemo-mechanics of phase transitions and fracture of battery electrodes. He and Professor Yet-Ming Chiang have developed a flow battery that utilizes co-suspensions of solid state electrode and electronically conductive particulates. They co-founded a company, 24M, to produce grid scale energy storage soluntions.. Professor Carter is recognized as one of DMSEs most innovative instructors. He is a MacVicar Fellow and has received the MIT School of Engineering Bose Teaching Award. ...
Four sets of nonreactive solute transport experiments were conducted with micromodels. Each set consisted of three experiments with one variable, i.e., flow velocity, grain diameter, pore-aspect ratio
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Zhang, C., Hernandez-Garcia, A., Jiang, K., Gong, Z., Guttula, D., Ng, S.Y., Malar, P.P., van Kan, J.A., Dai, L., Doyle, P.S., de Vries, R., and an der Maarel, J.R.C., "Amplified Stretch of Bottlebrush-Coated DNA in Nanofluidic Channels", Nucleic Acids Res., 41, e189, 2013. pdf reprint ...
The analyzer has detected a potential error that may lead to an infinite loop. When you deal with the std::istream class, calling the eof() function is not enough to terminate the loop. If data reading fails, a call of the eof() function will always r...
From: Max Reitz ,[email protected], Signed-off-by: Max Reitz ,[email protected], Message-Id: ,[email protected], Reviewed-by: Vladimir Sementsov-Ogievskiy ,[email protected], Tested-by: Vladimir Sementsov-Ogievskiy ,[email protected], Tested-by: Claudio Fontana ,[email protected], (cherry picked from commit ae159450e161b3e1e2c5b815d19632abbbbcd1a1) Signed-off-by: Michael Roth ,[email protected], --- tests/qemu-iotests/028 , 19 +++++++++++++++++++ tests/qemu-iotests/028.out , 11 +++++++++++ 2 files changed, 30 insertions(+) diff --git a/tests/qemu-iotests/028 b/tests/qemu-iotests/028 index 797dae5350..1e52986b74 100755 --- a/tests/qemu-iotests/028 +++ b/tests/qemu-iotests/028 @@ -142,6 +142,25 @@ TEST_IMG=${TEST_IMG}.copy io_zero readv $(( offset + 32 * 1024 )) 512 1024 32 _check_test_img +echo +echo === Reading across backing EOF in one operation === +echo + +# Use a cluster boundary as the base end here +base_size=$((3 * 1024 * 1024 * 1024)) + ...
A simple, sensitive and separative method for the photometric determination of inorganic anions was developed on the basis of suppressed electroosmosis by using a common silica capillary and a simple migrating solution. During the analysis of analyte anions by capillary zone electrophoresis, electroosmotic flow in a silica capillary was suppressed by using low-pH migrating solutions containing sodium sulfate. The stacking effect of sulfate ion was utilized for analyte concentration. Four kinds of inorganic analyte anions examined were detected in sharp signals, and the separation of a nitrate and a nitrite ion was improved by using the low-pH migrating solution with no decrease in detection sensitivity. Calibration graphs for nitrate and nitrite ions showed good linearity in the concentration ranges from about 10(-5) to 10(-4)mol dm(-3), with the detection limit for nitrate ion 4×10(-6)mol dm(-3). Separations of organic anions, such as aromatic sulfonate and carboxylate ions, were also ...
Many cellular functions are regulated through protein isoforms. Changes in the expression level or regulatory dysfunctions of isoforms often lead to developmental or pathological disorders. Isoforms are traditionally analyzed using techniques such as gel- or capillary-based isoelectric focusing. However, with proper electroosmotic flow (EOF) control, isoforms with small pI differences can also be analyzed using capillary zone electrophoresis (CZE). Here we demonstrate the ability to quickly resolve isoforms of three model proteins (bovine serum albumin, transferrin, α1-antitrypsin) in capillaries coated with novel dynamic coatings. The coatings allow reproducible EOF modulation in the cathodal direction to a level of 10-9 m2V-1s-1. They also appear to inhibit protein adsorption to the capillary wall, making the isoform separations highly reproducible both in peak areas and apparent mobility. Isoforms of transferrin and α1-antitrypsin have been implicated in several human diseases. By coupling ...
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A nonaqueous, hybrid metal-organic redox flow battery based on tailored anthraquinone structure is demonstrated to have an energy efficiency of ∼82% and a specific discharge energy density similar to those of aqueous redox flow batteries, which is due to the significantly improved solubility of anthraquinone
Answer. The overall charge within the capillary or the matrix has the greatest impact on resolution when using capillary electrophoresis (CE). With charge zonal electrophoresis (CZE) or other electrophoresis assays, the pH itself is more important because it dictates the number of charge zones (theoretical plates) within the capillary and how fast or slow the electroosmotic flow (EOF) will be if using a non-coated capillary. If using a gel polymer buffer, then more emphasis is placed on the polymers and their interaction with the analyte, as well as suppressing the EOF (unless a coating is used) to effect resolution. Capillary coatings added to the inner wall negate EOF, which then provides a more sample charge-based environment--whereby the molecule of interests overall net charge will determine the ability for it to resolve well in an electric field ...
Active development of compact analytical instruments suitable for point-of-care testing (POCT) requires optimization of existing methods. To aid the development of capillary gel electrophoresis instruments for POCT, we attempted to separate polymerase chain reaction products (small DNAs) using a short, fused silica capillary coated with an acrylamide (AM)/acrylic acid (AA) copolymer (poly(AM-co-AA)). To realize the high capability of this capillary to separate small DNAs, the magnitude of electroosmotic flow (EOF) was controlled by varying the content of negatively charged AA in the copolymer, which significantly affected the separation ability. At an AA content ≥3.75 mol %, sample DNAs could not be injected into the copolymer-coated capillary owing to strong EOF, whereas a 100 bp DNA ladder sample was successfully separated at an AA content of ≤3.5 mol %, showing that even slight AA content variations impact DNA flow. EOF values measured using a neutral coumarin 334 solution suddenly decreased at
A wirelessly powered and controlled biased-AC electroosmotic (biased-ACEO) lab-on-a-film (LOF) is presented here for particle and fluid manipulation. Amplitude modulation (AM) and inductive coupling are used for wireless transmission of low frequency signals required for excitation of biased-ACEO effects employed by the LOF for microfluidic functions. The LOF consists of a receiving coil (for receiving inductively transmitted high frequency signals), surface mounted devices (for recovering a low frequency AC signal) and an array of interdigitated electrodes (IDE, for excitation of biased-ACEO effects). Unlike existing wireless lab-on-a-chip devices that have cumbersome set-ups, require high voltages and perform only one microfluidic function, the presented LOF has a compact and flexible structure, works at very low voltage ranges, and can perform several microfluidic operations corresponding to a wirelessly-controlled voltage. When the level of the demodulated signal over the IDE is about 0.7 V, ...