In traditional hanging-insert workflows, media changes are a slow, manual bottleneck. Researchers must lift each insert—often with tweezers—to access the narrow gap between insert and well for pipetting or aspiration. This labor-intensive step not only adds time and variability but also risks disturbing delicate cellular layers. Now, WPI’s 24-Well Auto Exchange Cell Culture Plate fundamentally reshapes this workflow by combining smart well geometry, integrated fluidics, and robust insert seating to enable fully automated, multichannel TEER measurement on the EVOM™ Auto—and to simplify every step of media exchange and sampling, whether done by hand or robot. It enables seamless media exchange and multichannel TEER measurements without ever lifting an insert.

EVOM™ GxP compliance Module is 21 CFR Part 11 compliant software that meets the FDA's requirements for electronic records and signatures. When running the EVOM™ Auto with the GxP.

WPI’s EVOM™ line of transepithelial electrical resistance (TEER) measurement systems use silver-silver chloride electrodes for taking measurements. Our newest automated TEER measurement unit, the EVOM™ Auto, is available with an optional GxP module to ensure 21 CFR Part 11 compliance. GxP represents the quality guidelines in place to ensure standards are met. It is used for protocols like Good Laboratory Practice, Good Pharmaceutical Practice, Good Clinical Practice, Good Manufacturing Practice, and Good Research Practice.

Regular maintenance keeps your EVOM™ Auto GxP electrodes performing optimally. Periodically, you will need to re-chloride your electrodes. Just follow the steps shown in this video.

EVOM™ Auto with GxP powered by TotalLab automates your TEER measurements with the confidence that your data security complies with FDA’s 21 CFR Part 11 regulations.

You may calibrate the electrode array head using the internal reference resistor. Nothing involving the motor movement happens.

The EVOM™ Auto automated TEER measurement system with the GxP module powered by TotalLab ensures that your data security complies with FDA 21 CFR Part 11 requirements. If you have customized parameters like electrode placement for a plate profile, you may reset all the parameter to their factory default settings. We’ll show you how.

EVOM™ Auto automates TEER measurement, and it is now available with a GxP module to meet the FDA’s 21 CFR Part 11 compliance regulations. Here we will see how to create a new project file in the EVOM™ Auto GxP client software. Two options are available for the GxP software, and creating a project works the same way in both Option A and Option B versions. However, you may only create a project with files in the EVOM™ Auto GXP Option A software. Option B only lets you store EVOM™ Auto data files in the project folder.

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 has manufactured TEER instrumentation, including the EVOM2, EVOM3, EVOM™ Manual, and Millicell® ERS-2 (a WPI OEM product), for over three decades. Millipore’s Millicell® ERS 3.0 recently became available and is NOT manufactured by WPI, nor validated or certified to be accurate for TEER measurement. WPI manufactured and validated product, like EVOM™ Manual, the proven gold standard for TEER measurement, ensure the accuracy and reproducibility of your work. Accept no substitutes.

Transepithelial/Endothelial Electrical Resistance (TEER) qualitatively measures cellular monolayer health and quantitatively evaluates cellular confluence by measuring the electrical resistance across a cell monolayer. It is commonly used to assess the integrity and permeability of cellular barriers, such as epithelial and endothelial cell layers in cell culture plates. Organ-on-Chip platforms are an emerging market for TEER applications. Let’s look at what TEER is and how it is used.

The EVOM™ Auto automates measurements of TEER in epithelial or endothelial monolayers cultured on 24-well or 96-well high throughput screening (HTS) plates utilizing our innovative EVOM technology, qualitatively measuring cell monolayer health and quantitatively measuring cellular confluence by reaching an increase or a plateau in tissue resistance. The autosampler has a 3-well rinse station for cleaning and stabilizing the electrodes. Now, sterile disposable rinse station inserts are available for your convenience. They fit over the 3-well base rinse station. You can simply throw out the disposable inserts with the solutions when you are changing plates. This short videos shows how easy they are to use.

Transepithelial/transendothelial electrical resistance (TEER) measurement is one of the most used practices to evaluate cellular health, such as cellular confluence, barrier integrity, or barrier function of cellular monolayers grown onto multiwells. The TEER measurement using WPI’s Epithelial Voltohmmeter (EVOM) is considered the gold standard because of its reliable measurements and numerous literature citations using various cell types. The EVOM™ Manual and EVOM™ Auto along with different choices of electrodes (STX4, STX HTS high throughput screening, EndOhm chambers, and multielectrode array for EVOM™ Auto) allow researchers to perform and analyze cell samples in 6, 12, and 24 removable inserts and 24 and 96 HTS multiwell plate formats. The major challenges researchers may encounter while performing studies to capture TEER measurement include:
·      Unstable read outs
·      Out of range values 
·      Inconsistent measurements among sample replicates or batches.
Consider the following factors to overcome any TEER measurement problems and obtain accurate and reliable measurements. 

EVOM™ Auto is WPI’s latest high throughput screening TEER measurement system with 24 and 96 HTS transwell plate measurement capability, and it offers easy options for switching between different plates. I will show you how to setup it up. The Interface Unit is the controller that establishes communication between the EVOM™ Auto software and the autosampler. 

EVOM™ Auto High Throughput (HTS) Transepithiel Electrical Resistance (TEER) Measurement System with 24 and 96 transwell capability can switch between different 24 and 96 HTS transwell plates by using matching electrode arrays and plate positioner. Here we demonstrate how to install a well plate. 

The EVOM™ Auto High Throughput (HTS) Transepithiel Electrical Resistance (TEER) Measurement System with 24 and 96 transwell capability has a removable electrode array head. Different electrode arrays can be used with the same system to analyze a variety of 24 and 96 transwell HTS plates. 

EVOM™ Auto High Throughput (HTS) Transepithiel Electrical Resistance (TEER) Measurement System with 24 and 96 transwell capability can switch between different 24 and 96 HTS well plates by using matching electrode arrays and plate positioners. Here we demonstrate how to switch to a 24 transwell plate after using a 96 transwell plate. 

The foundation of many research laboratories is the ability to do in vitro studies, which rely on the ability to culture cells in the laboratory. Cell culture technologies have advanced significantly, allowing researchers to successfully culture many types of cell lines.

The EVOM™ family of TEER measurement meters have been cited in over 16,000 peer-reviewed, scientific journal articles. The EVOM™ Manual has been designed to improve workflow efficiency, increase stability, and provide more repeatable measurements than older Trans Epithelial Electrical Resistance (TEER) meters including the Millipore MilliCell® ERS-2, Millipore MilliCell ERS and World Precision Instruments EVOM2, EVOM and EVOMX. Here’s a quick summary of benefits of the EVOM™ Manual versus the MilliCell ERS voltohmmeter.

Syringes have a wide range of applications in a laboratory setting due to their ability to accurately measure and dispense liquids. Common lab uses include transferring precise volumes of liquid samples from one container to another for dilution, mixing, reagent preparation, and sample extraction. You may be using them for analytical techniques, like chromatography (such as high-performance liquid chromatography (HPLC) or gas chromatography), spectrophotometry, and titration. Syringes are often used for precise dosing and delivery of reagents during chemical reactions and synthesis processes, or in life science research for aspirating media, adding growth factors or nutrients, and transferring cells. In medical and veterinary research, syringes are used for the injection or infusion of drugs, vaccines, or contrast agents into animal models or cell cultures. Researchers can use lab syringes to collect liquid samples, particularly in environmental monitoring, water quality analysis, or biological sample collection. In microfluidic applications and lab-on-a-chip systems, syringes are perfect for precision control of fluid volumes and flow rates.

WPI’s EVOM™ Technology is a well-established, non-invasive method to verify tissue integrity or barrier function, confluence, and tissue properties in 2-D and 3-D formats. To get the best TEER measurement results with WPI’s EVOM technology, you need to select suitable electrodes based on your application. 

Here are some criteria to consider when selecting a TEER measurement electrode.

In 2022, the United States Food and Drug Administration (FDA) approved 37 new drugs, of which 20 were chemical entities and 17 were biologics. In 2023, drug discovery remains strong with many new advancements a result of changing landscapes in both the types of drugs that are being developed and the new and innovative assay that are being launched to evaluate drugs preclinically. Therapeutic development is still highly focused on diseases that affect large populations of people for which there are lack of effective treatments, with 2023’s most anticipated drug launches expected to be in areas of cancer, Alzheimer’s disease, cardiovascular disease, and ulcerative colitis.

In 2022, the United States Food and Drug Administration (FDA) approved 37 new drugs, of which 20 were chemical entities and 17 were biologics. In 2023, drug discovery remains strong with many new advancements a result of changing landscapes in both the types of drugs that are being developed and the new and innovative assay that are being launched to evaluate drugs preclinically. Therapeutic development is still highly focused on diseases that affect large populations of people for which there are lack of effective treatments, with 2023’s most anticipated drug launches expected to be in areas of cancer, Alzheimer’s disease, cardiovascular disease, and ulcerative colitis.

If the EVOM™ Auto software switches from Resistance to TEER mode while you are selecting menu options, here's a quick tip:

Be careful when selecting Resistance mode, do not tap the background window and do not click on the side arrows.

Tapping the background window will switch you to TEER mode.

Instead, tap an option on the forefront square window to stay in Resistance mode.

EVOM™ Manual is WPI's newest instrument to measure Trans Epithelial Electrical Resistance (TEER). Let's look at what comes with the system and how easy it is to setup.

WPI's EVOM system is popular in the research community, both in academia and in industry, and it is commonly used for the evaluation of mammalian cellular health by measuring transepithelial/transendothelial electrical resistance (TEER or TER) of cellular layers. 

EVOM™ Manual is powered by the same EVOM™ technology as older EVOM models (EVOMX, EVOM, EVOM2 and EVOM3). It has advanced features for performing experiments more easily. With the new touchscreen display you can now store data as Microsoft® Excel files on a USB flash drive. Just remove the flash drive with all your recorded data from the EVOM™ Manual and plug it into a computer to access and plot your data. It is as simple as it sounds.