Cell barriers, such as the intestinal epithelium, blood–brain barrier, or corneal endothelium, are critical for controlling what enters and exits tissues. A compromised barrier can lead to disease, while a strong barrier is essential for maintaining health.

Understanding how our body's protective barriers function is crucial for advancing treatments and developing new therapies. For researchers, accurately measuring barrier integrity is vital in fields ranging from drug development to disease modeling. One of the most important tools scientists use to study these barriers is TEER (Transepithelial Electrical Resistance or Transendothelial Electrical Resistance). This powerful measurement technique provides valuable insights into the integrity and function of cellular barriers that protect our organs and tissues. TEER is a gold-standard, non-invasive technique for quantifying the integrity and permeability of cell monolayers grown in culture.

World Precision Instruments (WPI), the global leader in transepithelial electrical resistance (TEER) technology, in collaboration with SynVivo, a leader in organ-on-chip (OOC) solutions, is proud to announce the launch of the EVOMTM Chip – a revolutionary multiplex TEER system designed specifically for real-time, non-destructive monitoring of OOC platforms.

Co-developed to support SynVivo’s state-of-the-art Blood-Brain Barrier (BBB) OOC model, the EVOM™ Chip enables on-chip, multiplex TEER measurements with embedded electrodes. This innovation allows researchers and drug developers to continuously monitor up to 12 OOCs for barrier integrity while simultaneously enabling fluidics and imaging, offering hands-free operation with enhanced accuracy, precision, and reproducibility.

In barrier model research, the integrity of your cell monolayers isn’t just important—it’s everything. Whether you're studying epithelial transport, drug permeability, or disease modeling, your ability to trust your data hinges on the health of your cultures. That’s why so many researchers rely on Transendothelial/Transepithelial Electrical Resistance (TEER) as a simple, non-invasive, real-time quantitative evaluation of the integrity of your cellular barrier.

Transepithelial/Transendothelial Electrical Resistance (TEER) is a widely used quantitative technique to assess the integrity of tight junctions in cell monolayers. WPI’s EVOM™ is the gold standard for TEER measurement and is particularly valuable in studies involving drug transport, toxicology, inflammation, and organ-on-chip systems. TEER measurement provides fast and quantitative data and can be used as an efficient and cost-effective method for drug discovery and development.  There are certain biological and technical factors that are known to affect TEER readings. This article reviews the key variables that influence TEER outcomes in cell culture studies and how to ensure consistent TEER measurement analysis can be done by minimizing or eliminating the effects of these factors.

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.

In industries like pharmaceuticals and biotechnology, where regulatory compliance is critical, adhering to GxP (Good “X” Practices) is essential to ensuring product safety, quality, and efficacy. Non-compliance with these standards can lead to severe consequences, including product recalls, legal liabilities, and a tarnished brand reputation. In this article we look at the benefits of GxP for reducing risks and facilitating audits and inspections.

The EVOM™ Auto with GxP module allows you to synchronize the date and time of the EVOM™ Auto system to the computer. This date is used to time stamp data when acquiring data and when staging it for export.

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.

EVOM™ Auto is a high throughput screening (HTS) platform offering fast, non-invasive sample scanning by comparing electrical resistance measurements (transepithelial/transendothelial electrical resistance: TEER). TEER measurement experiments are simple to set up and less time consuming than more complex molecular studies. The GxP module offers 21 CFR Part 11 compliant software that is required by the FDA. In this video, we will see how to delete an EVOM™ Auto GxP measurement sequence you no longer need.

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.

EVOM™ Auto with the GxP module lets you perform automated transepithelial electrical (TEER) resistance with confidence that your data security complies with the FDA 21 CFR Part 11 regulations. Here we will see how to run or stop a scheduled measurement sequence.

WPI’s EVOM™ Auto simplifies transepithelial electrical resistance (TEER) measurement by automating measurements in 24- and 96-well plates. A GxP module powered by TotalLab is available to meet the FDA’s 21 CFR Part 11 compliance regulations. Before making measurements, you need to stabilize your electrodes. See how here.

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.

Petri cell culture dishes like WPI’s FluoroDishes™ are commonly used in laboratories, but they require precision and care to ensure the accurate results of your work. Let’s look at several common mistakes made with cell culture dishes and how you can avoid them.

WPI’s EVOM™ line of transepithelial electrical resistance (TEER) measurement systems is the industry standard with thousands of citations in peer-reviewed journals spanning over 40 years. Our newest automated TEER measurement unit, the EVOM™ Auto, works with both 24- and 96-well plates, and now it is available with an optional GxP module to ensure 21 CFR Part 11 compliance to satisfy FDA requirements. In this video you can see how to run, pause, and stop an experiment.

EVOM™ Auto GxP Module is an add-on for the EVOM™ Auto Automated TEER measurement system that ensure 21 CFR Part 11 compliance to satisfy FDA requirements. The EVOM™ Auto is used for making transepithelial electrical resistance (TEER) measurements when you are testing for cell confluency or barrier integrity when you are doing drug absorption studies, tissue engineering, disease model, QC of cell-based assays and more. In this video we will create a sequence to use with an EVOM™ Auto that has the GxP module.

When your transepithelial electrical resistance (TEER) measurement processes require 21 CFR Part 11 compliance to satisfy FDA requirements, WPI’s GxP module for use with the EVOM™ Auto is perfect. Powered by TotalLab, the software database ensured that your EVOM™ Auto TEER data is tracked and stored with appropriate electronic signatures and an extensive audit trail. EVOM™ Auto can be used to perform automated TEER measurement on both 24- and 96-well plates. In this video you can see how to prepare your data for downloading.

EVOM™ GxP compliance Module is 21 CFR Part 11 compliant software that meets the FDA's requirements for electronic records and signatures. It work with the EVOM™ Auto autosampler.  In this video we launch the EVOM™ Auto GxP software from within EVOM™ Auto GxP Client.

Transepithelial electrical resistance (TEER) is a methodology that has been used for several decades to measure the resistance across a monolayer of cells to evaluate the barrier function of a cell layer. Historically, TEER measurements were utilized as a basic biological tool as researchers evaluated the permeability of biological layers and the functionality of tight junctions between various cell types. More recently, the utility of TEER measurements has expanded into new and diverse applications in a variety of fields. New applications for TEER measurement that have recently emerged include drug delivery, toxicology, organ-on-chip technology, and quality control of cell therapies. Traditionally used to study the barrier function of epithelial tissues in vitro, TEER has become a versatile and translational tool that has provided valuable insights into the integrity and permeability of complex engineered cell and tissue models as well as quality control measurements for cell-based products.

See how WPI equipment is being used by researchers to advance organ on a chip (OOC) to improve the outcomes of pregnancies. WPI is working with Dr. Ramkumar Menon, director of UTMB Obstetrics and Gynecology’s Division of Basic Science and Translational Research, who is using Transepithelial Electrical Resistance (TEER) to explore ways to minimize pre-term births.