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At least 883 records · Page 49Linked to original sources
PubMed2003

In vivo modulation of hippocampal epileptiform activity with radial electric fields.

PURPOSE: Electric field stimulation can interact with brain activity in a subthreshold manner. Electric fields have been previously adaptively applied to control seizures in vitro. We report the first results from establishing suitable electrode geometries and trajectories, as well as stimulation and recording electronics, to apply this technology in vivo. METHODS: Electric field stimulation was performed in a rat kainic acid injection seizure model. Radial electric fields were generated unilaterally in hippocampus from an axial depth electrode. Both sinusoidal and multiphasic stimuli were applied. Hippocampal activity was recorded bilaterally from tungsten microelectrode pairs. Histologic examination was performed to establish electrode trajectory and characterize lesioning. RESULTS: Electric field modulation of epileptiform neural activity in phase with the stimulus was observed in five of six sinusoidal and six of six multiphasic waveform experiments. Both excitatory and suppressive modulation were observed in the two experiments with stimulation electrodes most centrally placed within the hippocampus. Distinctive modulation was observed in the period preceding seizure-onset detection in two of six experiments. Short-term histologic tissue damage was observed in one of six experiments associated with high unbalanced charge delivery. CONCLUSIONS: We demonstrated in vivo electric field modulation of epileptiform hippocampal activity, suggesting that electric field control of in vivo seizures may be technically feasible. The response to stimulation before seizure could be useful for triggering control systems, and may be a novel approach to define a preseizure state.

Amplifiers, Electronic↗
PubMed2000

Electrical stunning and exsanguination decrease the extracellular volume in the broiler brain as studied with brain impendance recordings.

Electrical stunning in the process of slaughtering poultry is used to induce unconsciousness and immobilize the animal for easier processing. Unconsciousness is a function of brain damage. Brain damage has been studied with brain impedance recordings under ischemic conditions. This experiment studies brain impedance as a response to a general epileptiform insult caused by electrical stunning and ischemia caused by exsanguination. Brain impedance was recorded in 10 broiler chickens for each of three killing methods: whole body electrical stunning, which induces cardiac arrest; head only electrical stunning followed by exsanguination; and exsanguination without stunning. Brain impedance was converted into relative extracellular volume (ECV) values. Results showed that, immediately after electrical stunning, the ECV decreased 5.5% from base ECV. With exsanguination only, the ECV decreased from base ECV only after 4 min after neck cutting. The ECV decrease after 10 min did not differ between treatments. With a time of 228 s to reach one-half of the ECV decrease found at 10 min, electrical stunning resulted in a much faster change in ECV than exsanguination only (373 s). Within the head only stunning group, six animals showed a response similar to that found with whole body stunning; the other four animals responded similarly to the animals that were exsanguinated only. It was concluded that brain impedance recordings used with electrical stunning reflect brain damage. This damage was both epileptic and ischemic in nature. Whole body stunning induced immediate brain damage, suggesting that an adequate stun was delivered. The dual response found with head only stunning might indicate that this stunning method does not always produce an adequate stun.

Abattoirs↗
PubMed2005

Electrical inhibition of lens epithelial cell proliferation: an additional factor in secondary cataract?

Cataract is the most common cause of blindness but is at least curable by surgery. Unfortunately, many patients gradually develop the complication of posterior capsule opacification (PCO) or secondary cataract. This arises from stimulated cell growth within the lens capsule and can greatly impair vision. It is not fully understood why residual lens epithelial cell growth occurs after surgery. We propose and show that cataract surgery might remove an important inhibitory factor for lens cell growth, namely electric fields. The lens generates a unique pattern of electric currents constantly flowing out from the equator and entering the anterior and posterior poles. We show here that cutting and removing part of the anterior capsule as in cataract surgery significantly decreases the equatorial outward electric currents. Application of electric fields in culture inhibits proliferation of human lens epithelial cells. This inhibitory effect is likely to be mediated through a cell cycle control mechanism that decreases entry of cells into S phase from G1 phase by decreasing the G1-specific cell cycle protein cyclin E and increasing the cyclin-Cdk complex inhibitor p27kip1. Capsulorrhexis in vivo, which reduced endogenous lens electric fields, significantly increased LEC growth. This, together with our previous findings that electric fields have significant effects on the direction of lens cell migration, points to a controlling mechanism for the aberrant cell growth in posterior capsule opacification. A novel approach to control growth of lens epithelial cells using electric fields combined with other controlling mechanisms may be more effective in the prevention and treatment of this common complication of cataract surgery.

Animals↗
PubMed1990

Rhabdomyolysis due to pulsed electric fields.

High-voltage electrical trauma frequently results in extensive and scattered destruction of skeletal muscle along the current path. The damage is commonly believed to be mediated by heating. Recent experimental and theoretical evidence suggests, however, that the rhabdomyolysis and secondary myoglobin release that occur also can result from electroporation, a purely nonthermal mechanism. Based on the results of a computer simulation of a typical high-voltage electric shock, we have postulated that electroporation contributes substantially to skeletal muscle damage and could be the primary mechanism of damage in some cases of electrical injury. In this study, we determined the threshold field strength and exposure duration required to produce rhabdomyolysis by the electroporation mechanism. The change in the electrical impedance of intact skeletal muscle tissue following the application of short-duration, high-intensity electric field pulses is used as an indicator of membrane damage. Our experiments show that a decrease in impedance magnitude occurs following electric field pulses that exceed threshold values of 60 V/cm magnitude and 1-ms duration. The field strength, pulse duration, and number of pulses are factors that determine the extent of damage. The effect does not depend on excitation-contraction coupling. Electron micrographs confirm structural defects created in the membranes by the applied electric field pulses, and these represent the first clear demonstration of rhabdomyolysis in intact muscle due to electroporation. These results provide compelling evidence in support of our postulate.

Animals↗
PubMed1999

In vivo evaluation of coralline hydroxyapatite and direct current electrical stimulation in lumbar spinal fusion.

STUDY DESIGN: An animal model of posterolateral intertransverse process lumbar spinal fusion using autologous bone, coralline hydroxyapatite, and/or direct current electrical stimulation. OBJECTIVES: To evaluate the effect of an osteoconductive bone graft substitute and direct-current electrical stimulation on the rate of pseudarthrosis in a rabbit spinal fusion model. SUMMARY OF BACKGROUND DATA: Conventional techniques for the surgical treatment of degenerative conditions in the lumbar spine have a substantial failure rate and associated morbidity. Bone graft substitutes and electrical stimulation are alternative techniques to enhance fusion rates and limit the morbidity associated with posterolateral intertransverse process fusion using autologous iliac crest bone graft. METHODS: Fifty-three adult female New Zealand White rabbits underwent single-level lumbar posterolateral intertransverse process fusion. Animals were assigned to one of four groups using either autologous bone (Group I), coralline hydroxyapatite with autologous bone marrow aspirate (Group II), coralline hydroxyapatite with a 40-microA implantable direct current electrical stimulator and bone marrow aspirate (Group III), or coralline hydroxyapatite with a 100-microA implantable direct current electrical stimulator and bone marrow aspirate (Group IV). Animals were killed at 8 weeks, and fused motion segments were subjected to manual palpation, mechanical testing, and radiographic and histologic analysis to assess the fusion mass. RESULTS: Successful fusion was achieved in 57% (8/14) of animals in Group I, 25% (3/12) in Group II, 50% (6/12) in Group III, and 87% (13/15) in Group IV. Mean stiffness and ultimate load to failure were significantly higher in Group IV than in all other groups (P < 0.05). Histologic analysis demonstrated a qualitative increase in fusion mass in Group IV versus all other groups. CONCLUSIONS: Direct-current electrical stimulation increased fusion rates in a dose-dependent manner in a rabbit spinal fusion model. Coralline hydroxyapatite is an osteoconductive bone graft substitute, and thus requires an osteoinductive stimulus to ensure reliable fusion rates. Furthermore, coralline hydroxyapatite and direct current electrical stimulation can be used together to increase fusion rates in a rabbit spinal fusion model while avoiding the morbidity associated with harvesting iliac crest bone.

Animals↗
PubMed1969

Light scattering and birefringence changes during activity in the electric organ of electrophorus electricus.

1. In an attempt to obtain information about structural changes related to electrical activity in Electrophorus electroplates, we have determined the size and time course of the changes in light scattering and in bire-fringence that occur during and after the discharge of the electric organ.2. The changes in light intensity detected with a photomultiplier were never greater than 0.2% for a single discharge, and were often much smaller than this, but records with an acceptable ratio of signal to noise could be obtained by signal-averaging techniques.3. A single stimulus led to a decrease, then an increase, and finally another decrease in the light scattered by slices of the main electric organ. These three phases were designated E1, E2 and E3.4. E1 started at the beginning of the action potential, and its peak was reached at the same time as the completion of repolarization, even when the repolarization was delayed by cooling or hastened by drawing larger currents from the tissue.5. E2 was proportional to the integral of the current flowing through the slice of electric organ, and may arise from the swelling and shrinking of the tubules that stud the faces of the electroplates. It developed within a millisecond or two of the start of an applied current, and lasted for about 100 msec.6. E3 was a variable decrease in scattering that lasted for some seconds.7. A stimulus also led to a transient increase in the birefringence of the electric organ. The optical change followed the change in electrical potential across the innervated faces of the electroplates with a delay of somewhat under 50 musec.8. This voltage-dependent change in birefringence may arise from a Kerr effect (electric birefringence) in the membrane or from compression of the membrane.

Action Potentials↗
PubMed1995

Contribution of SK and BK channels in the control of catecholamine release by electrical stimulation of the cat adrenal gland.

1. Transmural electrical stimulation (10 Hz, 1 ms, 40 V for 10 s) of cat adrenal glands perfused at room temperature with Krebs-Hepes solution produced catecholamine secretory responses which were reproducible when stimulations were applied at 5 min intervals. Such responses were inhibited about 20% by atropine (1 microM) and 80% by hexamethonium (30 microM). Apamin (100 nM) increased the secretory response 2.5-fold in the presence of atropine and 8-fold in the presence of hexamethonium. 2. Potentiation by apamin of secretory responses evoked by 100-pulse trains was similar at 5, 10 and 20 Hz (about 2-fold). When glands were continuously stimulated at 3 Hz, apamin increased 4-fold the initial secretion plateau. Continuous stimulation at a higher frequency (20 Hz) produced a sharp secretory peak followed by a small, sustained plateau; apamin did not alter this plateau. Apamin also enhanced the secretory responses obtained with sustained stimulation with acetylcholine (10 or 200 microM). 3. Secretion peaks induced by brief acetylcholine pulses (10 microM for 10 s) applied to isolated and superfused cat adrenal chromaffin cells were enhanced more than 3-fold by 100 nM apamin. Charybdotoxin (10 nM) did not enhance these secretory peaks. 4. In perfused cat adrenal glands, charybdotoxin (10 nM) affected neither the secretion evoked by trains of electrical stimulation applied at different frequencies nor the secretion evoked by acetylcholine pulses. 5. In 0.5 mM [Ca2+]o, apamin enhanced 3-fold the secretion evoked by electrical stimulation trains of 100 pulses (10 Hz, 10 s) and almost 6-fold the acetylcholine (10 microM for 10 s)-induced secretion. In 5 mM Ca2+, apamin enhanced the secretory responses to electrical stimulation and acetylcholine 2- and 10-fold, respectively. Charybdotoxin enhanced 2.5-fold the secretory response to electrical stimulation in 0.5 mM Ca2+, although this effect was not statistically significant. A synergistic interaction between the two toxins on catecholamine release induced by electrical stimulation was observed at low but not at high [Ca2+]o. 6. Simultaneous release of acetylcholine and catecholamines upon electrical stimulation was achieved in glands in which the endogenous acetylcholine stores in the splanchnic nerve terminals had been prelabelled by perfusion with [3H]choline. While apamin enhanced more than 2-fold the postsynaptic release of catecholamines, the presynaptic release of acetylcholine remained unaffected. 7. The results are compatible with the hypothesis that, under physiological conditions, Ca(2+)-activated SK channels present in chromaffin cells control the firing patterns of action potentials induced by the acetylcholine released from splanchnic nerves during stress.(ABSTRACT TRUNCATED AT 400 WORDS)

Acetylcholine↗
PubMed2005

Defining electrical communication in skeletal muscle resistance arteries: a computational approach.

Vascular cells communicate electrically to coordinate their activity and control tissue blood flow. To foster a quantitative understanding of this fundamental process, we developed a computational model that was structured to mimic a skeletal muscle resistance artery. Each endothelial cell and smooth muscle cell in our virtual artery was treated as the electrical equivalent of a capacitor coupled in parallel with a non-linear resistor representing ionic conductance; intercellular gap junctions were represented by ohmic resistors. Simulations revealed that the vessel wall is not a syncytium in which electrical stimuli spread equally to all constitutive cells. Indeed, electrical signals spread in a differential manner among and between endothelial cells and smooth muscle cells according to the initial stimulus. The predictions of our model agree with physiological data from the feed artery of the hamster retractor muscle. Cell orientation and coupling resistance were the principal factors that enable electrical signals to spread differentially along and between the two cell types. Our computational observations also illustrated how gap junctional coupling enables the vessel wall to filter and transform transient electrical events into sustained voltage responses. Functionally, differential electrical communication would permit discrete regions of smooth muscle activity to locally regulate blood flow and the endothelium to coordinate regional changes in tissue perfusion.

Animals↗
PubMed1996

Health risks of electric and magnetic fields caused by high-voltage systems in Finland.

Health risks of power-frequency electric and magnetic fields (EMF) in the generation and transmission of electric power were investigated in a program comprising nine separate projects. The central objectives were to assess the practical importance of electric and magnetic field exposure as a health risk, to produce data applicable to field management measures at a major power company, and to support and spur research activities on electric and magnetic fields as environmental agents. Electric and magnetic fields seemed to be weak environmental factors, but the findings were uncertain and controversial as to the health risks except that, electric field strengths (about 1.5 kV.m-1) found even in the vicinity of 110 kV power lines may cause interference with cardiac pacemakers. There is still a need, however, for further basic research focused on the interaction mechanisms of electric and magnetic fields and biological tissue.

Brain↗
PubMedDate not supplied

[Electrical stimulation of the vagal nerve: from experimental to clinical aspects].

INTRODUCTION AND AIMS: This review focuses its attention on the studies that have been conducted to determine the influence of electrical stimulation of the vagal nerve on experimentally induced convulsive activity and its application in the clinical field. The literature published to date describes an anticonvulsive effect on the seizures triggered by pharmacological agents and by electrical stimulation such as electroshock, and in the amygdaline electrical kindling model a delay in the generalisation of the convulsive activity is observed. DEVELOPMENT: The first experimental observations showed that electrical stimulation of the vagal nerve can have effects on EEG activity, including synchronisation and desynchronisation of the electrical activity of the brain, as well as promoting an increase in the amount of REM sleep. These observations served as the basis for the renewed interest in the electrical stimulation of the vagal nerve in experimental models and testing its effectiveness in patients with medication-resistant epilepsy. Nevertheless, the mechanisms accounting for the anticonvulsive effect remain unknown. CONCLUSIONS: These observations open up the possibility of studying the role played by neurotransmitters and neuromodulators in the anticonvulsive process of the electrical stimulation of the vagal nerve in experimental models of epilepsy and offer evidence of its possible action in the human brain.

Electric Stimulation↗
PubMed1994

Bipolar surface electrical stimulation of the vertebrate retina.

BACKGROUND: Retinitis pigmentosa with attendant photoreceptor loss can cause a profound visual handicap. We have postulated that an intraocular prosthesis that could electrically stimulate the inner retina might provide vision to some of these patients. For such a prosthesis to be feasible, electrical stimulation of the inner retina must elicit a focal retinal response. The stimulating current densities required to elicit such a response must not result in irreversible toxic reactions at the electrode-tissue interface. METHODS: To test the feasibility of this approach, we used bipolar platinum wire electrodes to electrically stimulate the inner retinal surface in bullfrog eyecup preparations and, using similar methods, we electrically stimulated rabbit eyes after injecting intravenous sodium iodate (40 mg/kg), a retinal pigment epithelial toxin with secondary effects on the photoreceptors. RESULTS: Surface electrical stimulation of the inner retina in normal eyes and in eyes with outer retinal degeneration can elicit a localized retinal response. The threshold stimulating currents resulted in charge densities of 2.98 microcoulombs per square centimeter (bullfrog), 8.92 microC/cm2 (normal rabbit), and 11.9 microC/cm2 (rabbit retinas with outer retinal degenerations). These charge densities are within the previously delineated safe limits for long-term electrical stimulation of neural tissue using platinum microelectrodes (100 microC/cm2). CONCLUSION: Multifocal electrical stimulation of the retina might be a viable approach to provide some vision to patients who have profound visual loss due to outer retinal degenerations.

Animals↗
PubMed1998

Functional analysis of activation of porcine oocytes by spermatozoa, calcium ionophore, and electrical pulse.

The present study was conducted to examine differences in the activation of pig oocytes induced by sperm penetration or the artificial stimulators calcium ionophore A23187 and electrical pulse. Cumulus-oocyte complexes were cultured in NCSU 23 medium supplemented with 10% pig follicular fluid and 0.57 mM cysteine for 44 hr and then freed from cumulus and corona cells prior to activation with A23187 or an electrical pulse or inseminated with frozen-thawed ejaculated semen. Cortical granule (CG) exocytosis, zona reaction, nuclear activation, and developmental ability were examined after treatment. A23187 and electrical pulse induced 75.7% and 76.9% of CGs to be released from oocytes. Sperm penetration induced 86.3% of CGs to be released from the oocytes, which was significantly higher (P < 0.05) than those induced by artificial stimulators. Activation induced by A23187 and sperm penetration resulted in a zona reaction, which prevented sperm penetration after insemination or reinsemination, respectively. Activation induced by electrical pulse, however, did not cause a zona block since the penetration rate (80%) of oocytes was not different (P > 0.05) from that in control oocytes (87%). Electrical pulse induced 87% of the oocytes to form a pronucleus(ei), with 53% failing to release the second polar body. A23187 induced 62% of oocytes to form a pronucleus(ei), and 81% of these oocytes released the second polar body. Sperm penetration induced 98-100% of the oocytes to release the second polar body and form a female pronucleus, and 88-89% of sperm penetrated oocytes formed a male pronucleus(ei). Blastocyst formation of oocytes exposed to spermatozoa, electrical pulse, and A23187 was 27%, 10%, and 4% at Day 6 and 28%, 11%, and 5% at Day 7, respectively (P < 0.05). More nuclei were observed in the blastocysts derived from in vitro fertilization (32.3 +/- 12.9) than artificial stimulators. These results indicate that different and possibly overlapping mechanisms may be involved in the activation of pig oocytes by spermatozoa, electrical pulse, and A23187.

Animals↗
PubMed1994

Exposure to magnetic fields among electrical workers in relation to leukemia risk in Los Angeles County.

To address the hypotheses that electrical workers are exposed to higher magnetic fields and are at higher risk of leukemia than nonelectrical workers, we performed a registry-based case-control study among men aged 20-64 years with known occupation who were diagnosed with cancer in Los Angeles County between 1972 and 1990. Controls were men with cancers other than those of the central nervous system or leukemia. Magnetic field measurements on workers in each electrical occupation and in a random sample of occupations presumed to be nonelectrical were used to estimate magnetic field exposures for each occupation. Among men in electrical occupations, 121 leukemias were diagnosed. With the exception of electrical engineers, magnetic field exposures were higher among workers in electrical occupations than in nonelectrical occupations. A weakly positive trend in leukemia risk across average occupational magnetic field exposure was observed (odds ratio [OR] per 10 milligauss increase in average magnetic field = 1.2, 95% confidence interval [CI] 1.0-1.5). A slightly stronger association was observed for chronic myloid leukemia, although only 28 cases occurred among electrical workers (OR 10 milligauss increase = 1.6, 95% CI = 1.2-2.0). The results were not materially altered by adjustment for exposure to several agents known or suspected to cause leukemia. Although not conclusive, these results are consistent with findings from studies based on job title alone that electrical workers may be at slightly increased risk of leukemia.

Adult↗
PubMed1981

General properties of the interaction between animals and ELF electric fields.

An analysis is given of the interaction between extremely low-frequency (ELF) electric fields and animals of arbitrary body shape. This analysis is based on three approximations which are valid in the ELF range: In living tissues, capacitive (displacement) currents are negligible compared to conduction currents; effects resulting from the finite velocity of propagation of electromagnetic fields are negligible; skin effect in living tissues is negligible. Major conclusions of the analysis are: (a) The electric field outside the body, the induced charge on the surface of the body, and the total current crossing any section through the body (eg, through the neck or limbs) are completely determined by the characteristics of the applied ELF electric field, the shape of the body, its location relative to ground and other conductors, and any conduction currents from the body to ground or other conductors. (b) All of the quantities in (a) can be measured using conducting animal models. (c) The magnitudes of the electric field outside the body and the induced charge density on the surface of the body are independent of frequency, in the ELF range, when the body is either insulated from or shorted to ground (and any other conductors in the system). (d) The only quantities affected by the electrical properties of the tissues comprising the body are the current density and electric field inside the body. (e) The electric field outside and inside a body will be unchanged by a scaled change in its size.

Air↗
PubMed2001

Intracellular effect of ultrashort electrical pulses.

A simple electrical model for biological cells predicts an increasing probability for electric field interactions with cell substructures of prokaryotic and eukaryotic cells when the electric pulse duration is reduced into the sub-microsecond range. The validity of this hypothesis was verified experimentally by applying electrical pulses with electric field intensities of up to 5.3 MV/m to human eosinophils in vitro. When 3-5 pulses of 60 ns duration were applied to human eosinophils, intracellular granules were modified without permanent disruption of the plasma membrane. In spite of the extreme electrical power levels applied to the cells thermal effects could be neglected because of the ultrashort pulse duration. The intracellular effect extends conventional electroporation to cellular substructures and opens the potential for new applications in apoptosis induction, gene delivery to the nucleus, or altered cell functions, depending on the electrical pulse conditions.

Cell Membrane↗
PubMed1985

Torpedo electromotor system development: neuronal cell death and electric organ development in the fourth branchial arch.

The fourth branchial arch of Torpedo marmorata has been examined at the light and electron microscopic level during development. Of interest was the determination of the extent of electric organ tissue reported to be present in this arch and its possible relationship to electromotoneuron cell death in the electric lobes. The main electric organ of the torpedo is derived from the hyoid and first three branchial arches and is innervated by four major electromotor nerves. Extensive electromotoneuron cell death occurs in the electric lobes and most notably in the posterior poles. This feature could be due to a tendency for these neurons to innervate the fourth branchial arch where little or no electric tissue is formed. Our findings support this conclusion but are not entirely consistent with the idea that a population mismatch has occurred. This is because cell death precedes the genesis of the target cells. The presence of innervated differentiated electric tissue in this arch is also reported, leading to the conclusion that Torpedo marmorata possesses an accessory electric organ.

Animals↗
PubMed1994

Immunocytochemical characterization of the synaptic innervation of a single spinal neuron, the electric catfish electromotoneuron.

The electric catfish, Malapterurus electricus, possesses electric organs that are innervated by a pair of identifiable electromotoneurons located within the cervical spinal cord. The pattern of synaptic innervation of the electromotoneurons can be revealed by an antibody against the synaptic vesicle protein SV2. Both somata and proximal dendrites are densely innervated. Several transmitters contribute to this innervation. Glutamate, the neurotransmitter of the dorsal root sensory fibers, reveals a weak punctuate immunoreactivity. The previously described electrical synapses of the electromotoneurons were visualized by an antibody against a gap-junctional protein. In contrast to the electromotoneurons of other electric fish, the electric catfish electromotoneurons possess many inhibitory synapses. With antibodies against glycine and against the glycine receptor, a dense immunoreactivity of the surface of the somata and proximal dendrites can be revealed. The glycine receptor-like immunoreactivity exhibits a patch-like distribution similar to that revealed by the anti-SV2 antibody. gamma-Aminobutyric acid (GABA)-immunopositive terminals contribute to the inhibitory electromotoneuron innervations to a lesser degree. The chemical characteristics of the electromotoneuron innervations of Malapterurus resemble those of other spinal motoneurons rather than spinal electromotoneurons of other electric fish. Thus our immunocytochemical study supports the view that the pattern of electromotoneuron innervations in Malapterurus reveals little specialization. The capacity for information processing required for the control of the electric organ discharge appears to be achieved by the increased integrational capacity of the newly evolved multiple dendrites and not by an additional parallel channel specific for the electromotor system.

Animals↗
PubMed2006

Improved theory of cyclical electrical field flow fractionation.

Previously reported theories for cyclical electrical field flow fractionation (CyElFFF) are severely limited in that they do not account for diffusion, steric, or electric double layer effects. Experiments have shown that these theories overpredict the retention of particles in CyElFFF. In this work, we present a model for prediction of steric, diffusion, and electrical effects. The electrical double layer effects are treated using a lumped electrical circuit model that accounts for the field shielding by the electrical double layer formed at the electrode-carrier interface. The electrical effects are shown to dominate retention times and outweigh the contributions of diffusion and particle size. Detailed results from the simulations are presented in this work, and a comparison between the theoretical and experimental results obtained from the retentions of polystyrene particle standards is presented in this paper. The models are shown to correctly predict the retention of the polystyrene standards in CyElFFF with a reasonable error, while existing models are shown to have significant failings.

Electricity↗