TEER

by Benjamin Dubansky, PhD, Animal Physiologist/Researcher An Ussing Chamber is used when performing barrier studies across an excised epithelial tissue. Similar measurements can be made in well plates using an EVOM series TEER Measurement Meter, which is used for epithelial tissue that is grown to confluence in a cell culture well. While EVOM measurements are only qualitative, your throughput is much greater with an EVOM3. The EVOMs are portable and much more economical than an Ussing Chamber. Here Ben Dubansky, PhD explains the differences between EVOMs and Ussing chambers. The EVOM is a special kind of voltmeter for measuring electrical properties across a layer of cells in culture or a biological membrane. We are measuring TEER (TER) - Transepithelial Electrical Resistance. The

by Benjamin Dubansky, PhD, Animal Physiologist/Researcher The EVOM is a special kind of voltmeter for measuring electrical properties across a layer of cells in culture or a biological membrane. Here's a few things I like about the new EVOM3.   There's a couple things I like about the EVOM3 better than the older models. You can charge it. These ones had batteries which are fine, and they had a power plug. But when you use the power plug, you get a little bit electrical noise, and the signal's not quite as stable. When you have a good battery in here, the charge

by Benjamin Dubansky, PhD, Animal Physiologist/Researcher The EVOM is a special kind of voltmeter for measuring electrical properties across a layer of cells in culture or a biological membrane. It is the most commonly used commercial system for measuring across a layer of cultured cells. We are measuring TEER (TER) - Transepithelial Electrical Resistance. The EVOM3 allows us to zoom in and measure either resistance or voltage across these membranes or cells in culture.     Why was it invented? The EVOM (Epithelial Volt Ohm Meter) was designed in the 80’s. It was invented b

After 12 years, the next generation of the EVOM is born. Used for measuring Transepithelial Electrical Resistance (TEER) and monitoring the confluence of cell monolayers in culture well plates the EVOM3 TEER Measurement System enables researchers to carry out experiments more efficiently by improving the workflow, and increasing the stability and accuracy of readings over that of the EVOM2.  Here are six of the EVOM3 improvements.    

The NEW EVOM3 Epithelial Volt/Ohm Meter delivers improved workflow efficiency, increased stability and more repeatable measurements than traditional Trans Epithelial Electrical Resistance (TEER) meters. Here are seven things you will love about the new EVOM3.     1. It has an intuitive Touchscreen Display Providing users with vital feedback during experimental measurements, the EVOM3’s large touch screen offers a range of informational views. The new graphical displays for trend analysis and measurement values helps you deliver a simple, stepwise methodology during experimental measurements. The touch screen interface has an intuitive, easy-to-use menu for configuration and calibration that is designed to eliminate human errors and reduce experimental processing time. 2. EVOM3 offers Auto Data Logging Eliminating the need to log data by hand, the EVOM3 writes the resistance or voltage information to a USB drive in CSV format for easy transfer to spreadsheets and data analysis programs. 3. With the EVOM3 you get Hands Free Recording When used with the footswitch, it enables hands-free recording of measurements. 4. You can make Quick, Easy, Reliable Readings At the heart of the EVOM3 is our latest processor and circuitry, providing users with quick, easy and reliable readings due to its fast stabilization, automatic twenty times sampling average and low noise d

  Epithelial and endothelial cells are known for their barrier function like selective permeability. Lung tissue is comprised of epithelial cellular layers, residing adjacent to endothelial layers and allowing exchange of oxygen and carbon dioxide between lung and blood. Currently, the biomedical research community’s major focus area is to understand the details of the infection caused by this novel coronavirus (2019-nCoV) or by similar viruses. This new virus can disrupt the lung’s normal cleaning ability to get rid of foreign particles in the lung, and the selective permeability or barrier function of the lung may become severely impaired. The adverse physiological effect may be sustained once the inflammatory cascade is initiated. Researchers in collaboration with clinicians are trying to develop vaccines and drugs to

EndOhm Chambers Re-engineered EndOhm chambers are designed for making accurate TEER measurement of epithelial and endothelial cell cultures. The design keeps the top and bottom electrodes at a fixed gap and maintains the sample (cell culture insert) in a centered position inside. This design minimizes the variability associated with electrode positioning and gap, making EndOhm chambers more accurate and capable of generating reproducible results. WPI made some recent upgrades to the EndOhm chambers. The NEW EndOhm Chamber is made of GLASS, making it easier to clean and more crack resistant. The chamber can be cleaned with ethanol, isopropanol, bleach, etc. The chambers are still compatible with the original EVOM and EVOM2™ meters. The apical electrode height is adjustable. The chamber comes with a spacer disk. (Video) The crystal clear glass chamber allows better visualization of apical electrode for accurate sample positioning. A new insert holder on the top of the chambers has tri-supports for three leg inserts. This helps keep your cell culture wells in the proper position (centered) when you are making measurements. Three sizes cover a range of well cup sizes from a variety of manufacturers. Make Precise Measurements Using WPI’s EVOM2™ resistance meter/epithelial volt meter, Endohm chambers provide reproducible resistance measurements of endothelial and epithelial monolayers grown in culture cups or inserts. Transfer cups from their culture wells to the Endohm chamber for measurement rather than using hand-held electrodes. The chamber and the cap each contain a pair of concentric electrodes: a voltage-sensing silver/silver chloride pellet in the center plus an annular current electrode. The height of the top electrode can be adjusted to fit cell culture cups from different manufacturers. Endohm’s circular disc electrodes, situated above and beneath the membrane, allow a more uniform current density across the membrane than a system using the STX2 electrodes. Compared with other resistance measurement methods, Endohm with EVOM2™ offers a much more convenient and economic solution to monitor the health of cellular monolayers in terms of TEER values. The EndOhm chamber (combined with the EVOM2™) applies an alternating form of current,  and the chamber design guides the current, creating a more uniform current density across the sample. The EndOhm and EVOM2™ system can produce reliable read outs, because it eliminates most common errors associated with electrode polarization and membrane capacitance. Endohm together with EVOM2™ offers an accurate and economical system to measure resistance of cellular monolayers.  More Info

WPI EndOhm chambers are used with WPI's EVOM2 meter for making TEER (transepithelial electrical resistance) measurements. Here Subhra shows the difference between hanging cell culture inserts and standing cell culture inserts.

WPI EndOhm chambers are used with WPI's EVOM2 meter for making TEER (transepithelial electrical resistance) measurements. Each EndOhm chamber comes with a "spacer" disk for calibrating the gap between the two chamber electrodes. A consistent gap ensures reliable measurements. Here Subhra shows how to calibrate your chambers.

WPI EndOhm chambers are used with WPI's EVOM2 meter for making TEER (transepithelial electrical resistance) measurements. After heavy use your background resistance measurement may start to rise. Your electrodes may need to be resurfaced to remove buildup of proteins, sugars and biological materials. Here Subhra demonstrates how to clean and resurface your EndOhm chambers.