EVOM™ for Proven TEER Measurement, Accept No Substitute
WPI has manufactured TEER instrumentation, including the EVOM, EVOMX, 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 has it any published evidence that supports its accuracy, precision or application of TEER measurement. WPI's manufactured and validated products, like EVOM™ Manual, the proven gold standard for TEER measurement, ensure the accuracy and reproducibility of your work. Accept no substitutes.
Your choice of equipment and technology plays a critical role in the accuracy and reliability of your data collection. Two tools commonly used today for measuring trans-epithelial electrical resistance (TEER) in cell culture systems are EVOM2 and Millicell® ERS-2, both manufactured by WPI, using the TEER technology invented by WPI (patented in 19901). Since 2008, WPI has been the Original Equipment Manufacturer (OEM) of Millipore’s Millicell® ERS-2. WPI handled the production, quality control, validation, supply, and second level support of the Millicell® ERS-2.
TEER Meter Comparison Chart
Proven EVOM™ Technology Use in Research Swells
Together, EVOM2 and Millicell® ERS-2 have been featured in thousands of peer reviewed publications, demonstrating the accurate, reproducible, and meaningful data that these instruments produce2-4. WPI’s EVOM™ Technology for TEER measurement is now globally validated as a reliable method to determine the resistance across a cell layer and a critical parameter in cell biology, tissue engineering, drug delivery, and barrier function studies.
Figure 1: Number of Publications Citing “Transepithelial Electrical Resistance” on https://pubmed.ncbi.nlm.nih.gov/ from 1990- July 11th, 2024. A total of 4,507 publications have cited TEER with 3,250 specifically citing WPI instrumentation.
EVOM2 and EVOM™ Manual Produce Similar Readings for Seamless Upgrade
In 2018 WPI launched the EVOM3, re-branded as the EVOM™ Manual in 2022, adding many features, while maintaining the integrity and precision of the data that is collected.5 The EVOM™ Manual features several improvements over the EVOM2 and Millicell® ERS-2, including:
- Automatic data logging
- Low noise design that improves accuracy and resolution
- Automatic 20X sample averaging to improve precision and stability
- Continuous data logging directly onto a PC.
Figure 2: While the EVOM Manual is more user-friendly and can measure a 24-well plate in 25% of the time it takes using EVOM2, the TEER readings are not statistically different between the two.
The EVOM™ Manual uses the same TEER technology as the EVOM2 and Millicell® ERS-2. With EVOM2 and Millicell® ERS-2 now both discontinued by WPI, upgrading your instrument to an EVOM™ Manual ensures reliability and continuity in the data (Figure 2). Established experimental models and assays do not have to be replicated and re-validated to compare data that is collected from these instruments, saving you significant time and resources in the transition from EVOM2 or Millicell® ERS-2 to EVOM™ Manual. EVOM™ Manual has a full array of compatible electrodes, including the STX4 (chopstick electrodes), the STX HTS (STX HTS EVOM high throughput screening electrode), and the line of EndOhm chambers. With an adapter it is even compatible with legacy electrodes.
ERS 3.0 Does Not Use EVOM™ Technology
In 2024, Millipore launched a new product, the Millicell® ERS 3.0, which was not developed or manufactured by WPI. While both the EVOM™ Manual and Millicell® ERS 3.0 devices serve a similar purpose, they differ significantly in terms of their proven reliability.
- Peer-Reviewed Data – While the EVOM™ Manual uses the TEER technology that has been the subject of thousands of peer-reviewed publications for nearly 35 years, the Millicell® ERS 3.0 has not had a peer-reviewed publication to date, and there is a stark lack of data publicly available for this instrument.
- Fundamental Design Differences – Millicell® ERS 3.0 also has significant changes that may impact the data that is obtained from it. For example, none of the EVOM™ or Millicell® ERS-2 legacy electrodes are compatible with the Millicell® ERS 3.0, and ERS 3.0 electrodes are made using gold, which has electrical properties that vary significantly from the Ag/AgCl used in the EVOM™ and ERS-2 electrodes.
Why Trust the EVOM™ Brand?
WPI’s EVOM™ technology has been a trusted name in the industry for decades. On the other hand, the Millipore Millicell® ERS 3.0 is a new entrant in the market, with no publicly available data, raising significant concerns regarding proof of its accuracy and reliability. The Millicell® ERS 3.0 is unvalidated for most of TEER applications, raising equal concern about the data it collects. The inability to seamlessly continue experiments and studies means a significant amount of time for a laboratory to implement the Millicell® ERS 3.0 into their workflows in the way that can be done easily with the EVOM™ Manual.
The reliability and consistency of data obtained from the EVOM™ Manual make it a trusted choice for researchers who prioritize accuracy and precision in their work. The change in manufacturing and unvalidated nature of the Millicell® ERS 3.0 raises concerns about the reliability of data collected from this system, casting a shadow of doubt on its effectiveness and suitability for critical research applications.
EVOM™ technology is the proven gold standard. Accept no substitutes.
References
- United States Patent Application: US4912060A. “Method and apparatus for electrical testing of membranes”
- Pubmed, National Library of Medicine: https://pubmed.ncbi.nlm.nih.gov/
- Bioz: https://www.bioz.com/
- WPI Publications: /scientific-publications
- EVOM Manual: /evm-mt-03-01-evomtm-manual-for-teer-measurement.html
