Multi-Electrode Array with a Planar Surface for Cell Patterning by Microprinting

Multielectrode arrays (MEAs) are devices for non-invasive electrophysiological measurements of cell populations. This paper describes a novel fabrication method of MEAs with a fully planar surface. The surface of the insulation layer and the surface of the electrodes were on one plane; we named this device the planar MEA (pMEA). The main advantage of the pMEA is that it allows uniform contact between the pMEA surface and a substrate for positioning of microfluidic channels or microprinting of a cell adhesive layer. The fabrication of the pMEA is based on a low adhesive Au sacrificial peel-off layer. In divergence from conventional MEAs with recessed electrodes, the electrodes of the pMEA lead across the sloped edge of the insulation layer. To make this, the profile of the edge of the insulation layer was measured and the impedance of the planar electrodes was characterized. The impedance of the pMEA was comparable with the impedance of conventional MEA electrodes. The pMEA was tested for patterning HL-1 cells with a combination of imprinting fibronectin and coating by antifouling poly (l-lysine)-graft-poly(ethylene glycol) (PLL-g-PEG). The HL-1 cells remained patterned even at full confluency and presented spontaneous and synchronous beating activity.

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Flexible Concentric Ring Electrode Array for Low-Noise and Non-Invasive Detection

2021 IEEE 34th International Conference on Micro Electro Mechanical Systems (MEMS) ◽

10.1109/mems51782.2021.9375276 ◽

2021 ◽

Author(s):

Zhongke Mei ◽

Nan Zhao ◽

Bin Yang ◽

Jingquan Liu

Keyword(s):

Electrode Array ◽

Ring Electrode ◽

Low Noise ◽

Concentric Ring ◽

Non Invasive

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AlGaN/GaN heterostructures for non-invasive cell electrophysiological measurements

Biosensors and Bioelectronics ◽

10.1016/j.bios.2007.06.014 ◽

2007 ◽

Vol 23 (4) ◽

pp. 513-519 ◽

Cited By ~ 22

Author(s):

Jinjiang Yu ◽

Shrawan Kumar Jha ◽

Lidan Xiao ◽

Qingjun Liu ◽

Ping Wang ◽

...

Keyword(s):

Non Invasive ◽

Electrophysiological Measurements ◽

Invasive Cell

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Detection of Amyotrophic Lateral Sclerosis (ALS) via Acoustic Analysis

10.1101/383414 ◽

2018 ◽

Cited By ~ 1

Author(s):

Raquel Norel ◽

Mary Pietrowicz ◽

Carla Agurto ◽

Shay Rishoni ◽

Guillermo Cecchi

Keyword(s):

Disease Progression ◽

Acoustic Analysis ◽

Voice Quality ◽

Non Invasive ◽

Frequent Monitoring ◽

In The Wild ◽

A Cell ◽

Speech Features ◽

Severity Of The Disease ◽

Lateral Sclerosis

ABSTRACTALS is a fatal neurodegenerative disease with no cure. Experts typically measure disease progression via the ALSFRS-R score, which includes measurements of various abilities known to decline. We propose instead the use of speech analysis as a proxy for ALS progression. This technique enables 1) frequent non-invasive, inexpensive, longitudinal analysis, 2) analysis of data recorded in the wild, and 3) creation of an extensive ALS databank for future analysis. Patients and trained medical professionals need not be co-located, enabling more frequent monitoring of more patients from the convenience of their own homes. The goals of this study are the identification of acoustic speech features in naturalistic contexts which characterize disease progression and development of machine models which can recognize the presence and severity of the disease. We evaluated subjects from the Prize4Life Israel dataset, using a variety of frequency, spectral, and voice quality features. The dataset was generated using the ALS Mobile Analyzer, a cell-phone app that collects data regarding disease progress using a self-reported ALSFRS-R questionnaire and several active tasks that measure speech and motor skills. Classification via leave-five-subjects-out cross-validation resulted in an accuracy rate of 79% (61% chance) for males and 83% (52% chance) for females.

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The electrical heart axis of the fetus between 18 and 24 weeks of gestation: A cohort study

PLoS ONE ◽

10.1371/journal.pone.0256115 ◽

2021 ◽

Vol 16 (12) ◽

pp. e0256115

Author(s):

Carlijn Lempersz ◽

Lore Noben ◽

Sally-Ann B. Clur ◽

Edwin van den Heuvel ◽

Zhouzhao Zhan ◽

...

Keyword(s):

Reference Electrode ◽

Frontal Plane ◽

Fetal Anomaly ◽

Detection Rates ◽

Non Invasive ◽

Combined Use ◽

Electrophysiological Measurements ◽

Fetal Electrocardiography ◽

The Right ◽

Electrocardiogram Ecg

Introduction A fetal anomaly scan in mid-pregnancy is performed, to check for the presence of congenital anomalies, including congenital heart disease (CHD). Unfortunately, 40% of CHD is still missed. The combined use of ultrasound and electrocardiography might boost detection rates. The electrical heart axis is one of the characteristics which can be deduced from an electrocardiogram (ECG). The aim of this study was to determine reference values for the electrical heart axis in healthy fetuses around 20 weeks of gestation. Material and methods Non-invasive fetal electrocardiography was performed subsequent to the fetal anomaly scan in pregnant women carrying a healthy singleton fetus between 18 and 24 weeks of gestation. Eight adhesive electrodes were applied on the maternal abdomen including one ground and one reference electrode, yielding six channels of bipolar electrophysiological measurements. After removal of interferences, a fetal vectorcardiogram was calculated and then corrected for fetal orientation. The orientation of the electrical heart axis was determined from this normalized fetal vectorcardiogram. Descriptive statistics were used on normalized cartesian coordinates to determine the average electrical heart axis in the frontal plane. Furthermore, 90% prediction intervals (PI) for abnormality were calculated. Results Of the 328 fetal ECGs performed, 281 were included in the analysis. The average electrical heart axis in the frontal plane was determined at 122.7° (90% PI: -25.6°; 270.9°). Discussion The average electrical heart axis of healthy fetuses around mid-gestation is oriented to the right, which is, due to the unique fetal circulation, in line with muscle distribution in the fetal heart.

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Non-invasive Fetal Electrocardiography for Intrapartum Cardiotocography

Frontiers in Pediatrics ◽

10.3389/fped.2020.599049 ◽

2020 ◽

Vol 8 ◽

Author(s):

Rik Vullings ◽

Judith O. E. H. van Laar

Keyword(s):

Heart Rate ◽

Doppler Ultrasound ◽

Fetal Heart Rate ◽

Fetal Heart ◽

Fetal Monitoring ◽

Irreversible Damage ◽

Scalp Electrode ◽

Non Invasive ◽

Electrophysiological Measurements ◽

Fetal Electrocardiography

Fetal monitoring is important to diagnose complications that can occur during pregnancy. If detected timely, these complications might be resolved before they lead to irreversible damage. Current fetal monitoring mainly relies on cardiotocography, the simultaneous registration of fetal heart rate and uterine activity. Unfortunately, the technology to obtain the cardiotocogram has limitations. In current clinical practice the fetal heart rate is obtained via either an invasive scalp electrode, that poses risks and can only be applied during labor and after rupture of the fetal membranes, or via non-invasive Doppler ultrasound technology that is inaccurate and suffers from loss of signal, in particular in women with high body mass, during motion, or in preterm pregnancies. In this study, transabdominal electrophysiological measurements are exploited to provide fetal heart rate non-invasively and in a more reliable manner than Doppler ultrasound. The performance of the fetal heart rate detection is determined by comparing the fetal heart rate to that obtained with an invasive scalp electrode during intrapartum monitoring. The performance is gauged by comparing it to performances mentioned in literature on Doppler ultrasound and on two commercially-available devices that are also based on transabdominal fetal electrocardiography.

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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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Usefulness of a Non-invasive Reporter System for Monitoring Reprogramming State in Pig Cells: Results of a Cell Fusion Experiment

Journal of Reproduction and Development ◽

10.1262/jrd.09-190a ◽

2010 ◽

Vol 56 (4) ◽

pp. 363-369 ◽

Cited By ~ 3

Author(s):

Akio OZAWA ◽

Eri AKASAKA ◽

Satoshi WATANABE ◽

Mitsutoshi YOSHIDA ◽

Kazuchika MIYOSHI ◽

...

Keyword(s):

Cell Fusion ◽

Reporter System ◽

Non Invasive ◽

A Cell

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An Integrated PDMS Microfluidic Device for Dielectrophoretic Separation of Malignant Cells

ASME 3rd International Conference on Microchannels and Minichannels, Part B cont’d ◽

10.1115/icmm2005-75063 ◽

2005 ◽

Author(s):

Thirukumaran T. Kanagasabapathi ◽

Colin Dalton ◽

Karan V. I. S. Kaler

Keyword(s):

Microfluidic Device ◽

Low Cost ◽

Polystyrene Latex ◽

Yeast Cells ◽

Microfluidic Channels ◽

Non Invasive ◽

Latex Beads ◽

Planar Electrodes ◽

And Performance ◽

Cancerous Cells

Dielectrophoresis (DEP) has been successfully applied and demonstrated to provide novel and non-invasive means for characterizing, manipulating, trapping, separating and isolating microscopic sized particles, including biological cells. In this article, we report on the design, fabrication and performance of a novel, low cost, integrated Poly(dimethylsiloxane) (PDMS)/DEP microfluidic device capable of controlled manipulation of microscopic sized cells and particles that can be simultaneously utilized both for DEP spectral analysis and cell sorting. We have prototyped microfluidic channels, with DEP microelectrodes incorporated within PDMS channels. Previously, we have evaluated the operation and performance of a prototype device using various dielectric and biological particles, including yeast cells and polystyrene latex beads. In this paper, we report initial experimental observations on malignant cancerous cells. Non-viable cells, due to positive DEP, were attracted to the planar electrodes at frequencies between 200–600 kHz and were clearly repelled from the electrodes, due to negative DEP, at frequencies above 10 MHz.

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