This website uses cookies to ensure you get the best experience on our website.
Read more
Epithelial Physiology
-
February 21, 2019
The WPI EVOM2 meter is used to measure TEER (transepithelial electrical resistance) in cell culture inserts. The STX2 electrodes with a static length may cause damage to Snapwell inserts. Here Subhra demonstrates how to use the adjustable STX3 electrode to prevent damage to your cell culture inserts.
-
February 21, 2019
WPI's EndOhm chambers are used with WPI's EVOM2 meter to measure TEER (transepithelial electrical resistance) in cell culture inserts. Three chamber sizes are available for 6-well plates, 12-well plates and 24-well plates. Here Subhra demonstrates how to choose an EndOhm chamber to match the cell culture inserts you are using.
-
February 21, 2019
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.
-
February 21, 2019
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.
-
November 20, 2015
For small batches of cell culture
Are you ready to perform experiments involving a cultured cell monolayer? If your monolayer has not reached confluence, you may have holes or gaps in the monolayer that would prevent collection of valid experimental data. When confluence is reached, the electrical resistance across the monolayer peaks and then plateaus. The EVOM2 meter was designed specifically for this application.
The EVOM2 is the ideal meter for use when you are making manual TEER measurements on small batches of cell cultures and do not require a high throughput system.
EVOM2 - Perfect for TEER
The EVOM2 was designed to measure TEER resistance without damaging the epithelial cells. It passes a constant current of low amperage...more
-
April 14, 2015
-
February 02, 2015
Here are some frequently asked questions (FAQ) about TEER measurement using an EVOM2.
- Are the electrical resistance and transepithelial electrical resistance (TEER) the same thing?
- What is an EndOhm chamber?
- How is an EVOM2 used for measuring confluence?
- Why use an EndOhm instead of a STX?
- How do I clean my electrode?
- What about electrode preconditioning?
- Can you give me a simple data acquisition system for TEER?
- What are the TEER measurement challenges that I may encounter?
- Can you suggest some experimental...more
-
November 11, 2014
The EVOM2 is the classic, hand-held instrument for making Trans Epithelial Electrical Resistance (TEER) measurements. The REMS system adds a robot and data recording for automated TEER measurements. There may be times when you don't have a robot, but would still like to have the data recording capabilities of the REMS system. With a little ingenuity, you can do just that. Here, we will show you how you can add data recording to your standard EVOM2...more.
-
May 30, 2014
What is REMS?
The REMS AutoSampler automates measurements of electrical resistance of transepithelial, transendothelial or Caco-2 cell membranes being grown to confluence on microporous filters of high throughput screening (HTS) 24- and 96-well microplates. It is a PC-controlled, tissue resistance measurement system that offers reproducibility, accuracy and flexibility for this kind of measurement. The ability of the REMS AutoSampler to precisely locate the electrode results in highly reproducible TEER measurements. TEER measurements are stored in the computer as the electrode moves from one well to the next. The Windows-based software provides user-friendly features to acquire, display and store the tissue resistance measurements.
Automated...more
-
April 08, 2014
The REMS AutoSampler automates measurements of electrical resistance of transepithelial, transendothelial or Caco-2 cell membranes being grown to confluence on microporous filters of high throughput screening (HTS) 24- and 96-well microplates. It is a PC-controlled, tissue resistance measurement system that offers reproducibility, accuracy and flexibility for this kind of measurement. Automated measurement of tissue resistance in cell culture microplates provides the important advantages of speed, precision, decreased opportunity for contamination and the instant availability of measured resistance data on a computer. These measurements are useful in applications such as drug bioavailability studies and studies on the mechanisms of drug transport.
-
November 18, 2013
One of our frequently asked questions (FAQs) concerns TEER measurements with an EndOhm. If the resistance readings from your ENDOHM don't stabilize, you may need to do some troubleshooting. Test the EVOM2
First, test your EVOM2 meter. The 1000Ω test resistor (WPI # 91750) can be used for this purpose.
- Insert the RJ-11 plug at the end of the test resistor into the Input port on the meter. ...more
-
October 11, 2013
With the development of a High Throughput Screening (HTS) protocol for faster drug discovery, a new line of cell culture filter plates have been introduced by several major cell culture insert manufacturers. These HTS plates normally have either 24 or 96 individual cell culture inserts "bonded" together as one plate so that it can be handled by a robot apparatus. In response to these developments, WPI has developed an automatic REMS system and a manual electrode, STX100, for TEER measurements using HTS plates. - Designed for use with 24-well HTS plates (Corning Costar and BD Falcon) and with 96-well plates (Millipore and BD Falcon)
- Improved accuracy down to 5Ω
- Sterilize with EtO, alcohol or bactericide
STX100's design is based on the same reliable design principle as the universally...more
-
October 11, 2013
Transepithelial Electrical Resistance TEER measurements is the most convenient, reliable and non-destructive method for evaluating and monitoring the growth of epithelial tissue cultures in vitro. The confluence of the cellular monolayer is quickly determined by a sharp increase in TEER. TEER measurement technology, which was first introduced by WPI in the mid-1980's, has since been perfected and expanded to include a range of TEER related manual and automatic instrumentation, including:
- EVOM² - Manual TEER measurement of epithelial cells in 24- and 96-well plates
- REMS AutoSampler - Automated system for High Throughput Screening (HTS)
EVOM2 Volt-Ohm Meter
...more -
October 11, 2013
The REMS AutoSampler automates measurements of electrical resistance of transepithelial, transendothelial or Caco-2 cell membranes being grown to confluence on microporous filters of high throughput screening (HTS) 24- and 96-well microplates. It is a computer-controlled, tissue resistance measurement system that offers reproducibility, accuracy, flexibility and ease-of-operation for this kind of measurement. Automated measurement of tissue resistance in cell culture microplates provides the important advantages of speed, precision, decreased opportunity for contamination and the instant availability of measured resistance data on a computer. These measurements are useful in applications such as drug bioavailability studies and studies on the mechanisms of drug transport.
The main components of the REMS AutoSampler include:
- Robotic sampler that moves the electrode over each well of the microplate
- Electrode which is located on the robotic arm
- Base plate for the 24-and 96-well tray
- Windows-based data acquisition card
- REMS interface unit
- REMS software to operate the system on a Windows-based computer
The REMS AutoSampler automates TEER measurements previously made with WPI's EVOM2 Epithelial Voltohmmeter. Automated tissue resistance measurements up to 20kΩ can be performed on 24- or 96-well HTS microplates. Microplates presently supported include the Corning Costar HTS Transwell-24, Falcon HTS Multiwell insert systems, and Millipore Multiscreen™ CaCo 96-well plate. The REMS AutoSampler is designed to facilitate integration with other robotic systems. Special locating bars are installed on the REMS base platform that allow other system robots to place an HTS tray into a precise location on the REMS base.
The REMS AutoSampler automatically measures and records tissue resistance from a user-specified matrix of culture wells on the microplate. According to the specified sequence, the robotic arm moves over the identified wells taking TEER measurements. By means of a x-y-z locating system, the electrode-containing arm is positioned precisely and reproducibly over each well. The ability of the REMS AutoSampler to reproducibly and precisely locate the electrode results in highly reproducible TEER measurements. TEER measurements are stored in the computer as the electrode moves from one well to the next. The Windows-based software provides user-friendly features to acquire, display and store the tissue resistance measurements.
The REMS electrode is compact and robust in design. Each of two rod-shaped probes, 1.5mm in diameter, consists of a pair of electrodes: one electrode for injecting current and the other for measuring the voltage. The use of two pairs of electrodes eliminates the error caused by the electrode-liquid interface. To take a measurement, the robot inserts one probe into the center of the filter well and the other into the opening slot of the 24- or 96-well plate. The use of AC current to measure resistance provides several advantages over DC current, including:
- Absence of offset voltages on measurements
- There is a zero net current being passed through the membrane, and therefore it is not adversely affected by a current charge
- No electrochemical deposition of electrode metal.
The REMS AutoSampler also features a rinse and calibration check station. If occasional rinsing of the REMS electrode is required, it maybe sent to a rinse...more
-
October 11, 2013
WPI's EndOhm chambers were designed for making TEER measurement of endothelial cell cultures in individual cups. The EndOhm chambers feature:
- Compatible with EVOM²
- Improved accuracy of 1-2Ω
- Accommodates 6mm, 12mm, 24mm cups and Costar Snapwell cup
- Sterilized with EtO, alcohol or a bactericide
Using WPI's EVOM² resistance meter, EndOhm chambers provide reproducible resistance measurements of endothelial tissue in culture cups. 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...more