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EVOM2

EVOM2

Trans Epithelial electric resistance (TEER) Measurements


  • Overview
  • Specifications
  • Accessories
  • Citations
  • Related Products

Overview

EVOM2 EVOM2 package contents

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Instruction Manual
/ Download as PDF

Application Note
/ Download as PDF

NEWER Model Available - Check out the EVOM™ Manual  HERE 

 ----------------------------------------------------------------------------------------------

Non-destructively test for epithelial monolayer confluence in 2D cell cultures

  • Measures trans-epithelial electrical resistance or trans-epithelilal voltage
  • Compatible with 12 and 24 well culture plate systems out of the box
  • Includes industry standard STX2 hand held “chopstick” electrodes
  • Analog output for recording resistance or voltage measurements
  • Auto ranging from 0-10 KΩ
  • Battery powered
  • Manual TEER measurement of epithelial cells in 6, 12, 24 and 96* well plates
  • BNC output for data acquisition system
  • Compatible with EndOhm chambers
  • *96-well plate measurement requires an STX100 series electrode.

During the last two decades TEER measurements have become universally established as the most convenient, reliable and non-destructive method to evaluate and monitor the growth of epithelial tissue cultures in vitro. The confluence of the cellular monolayer is quickly determined by a sharp increase in TEER. Recently there has been a significant surge of interest in introducing a combined electrode for resistance measurements in the Millipore 96-well PAMPA (parallel artificial membrane permeability assay) plate.

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.

EVOM2™ Epithelial Voltohmmeter

  • Manual TEER measurements of epithelial cells in 6-, 12-, and 24-well plates
  • Electrically isolated meter that plugs into a standard outlet for continual readout without push buttons
  • Compatible with Endohm chambers
  • STX2 manual electrodes and test electrode included with every meter
  • Free standing with tilt bail, making viewing results easy
  • Standard analogue BNC output port

Benefits

  • You can verify performance and calibrate the meter for TEER function using provided test resistor
  • Battery powered meter is portable
  • A variety of accessory electrodes are available for measuring TEER in 6- and 96-well fixed (HTS) and removable well culture systems (See STX100 series and Endohm electrodes)

Applications

  • TEER and trans-epithelial voltage measurements in 2D cell cultures

Making TEER Measurements to Determine Cellular Confluence

The EVOM was the first instrument designed specifically to perform routine Trans Epithelial Electrical Resistance (TEER) measurement in tissue culture research. EVOM2 is the next generation, redesigned for ease of use. The EVOM2 not only qualitatively measures cell monolayer health, but also quantitatively measures cellular confluence. The unique electronic circuit of the EVOM2™ and the included STX2  electrode detect the confluence of the cellular monolayer. When combined with WPI’s Endohm chamber, the EVOM2 can also be used to perform more accurate quantitative measurements or lower resistance measurements like transendothelial electrical resistance measurements. 

Isolated battery power for 10 hours of use

The isolated power source of the EVOM2™ was specifically designed to avoid adverse effects on tissue and the formation of electrode metal deposits, even when it is plugged into a standard wall outlet. Now, the EVOM2™ is always on when you need it. In addition, its rechargeable battery allows up to 10 hours of mobile use.

Accurate reading every time

The four-and-a-half digit readout provides a range of 1-9,999 Ω. The included test electrode lets you calibrate the resistance measurements for an accurate reading every time. An analog BNC output is standard with the EVOM2™, providing an output port for recording data or remote display of the EVOM2™ output.

Electrode pair to measure voltage, pass current

EVOM2™ comes complete with the popular STX2 “chopstick” electrodes, 4 mm wide and 1 mm thick. Each stick of the electrode pair contains a silver/silver-chloride pellet for measuring voltage and a silver electrode for passing current. The small size of each electrode is designed to facilitate placement of the electrodes into a variety of standard cell culture wells. 

    STX2      STX3

       STX2              STX3

The EVOM was the first instrument designed specifically to perform routine Trans Epithelial Electrical Resistance (TEER) measurement in tissue culture research. EVOM2 is the next generation, redesigned for ease of use. The EVOM2 not only qualitatively measures cell monolayer health, but also quantitatively measures cellular confluence. The unique electronic circuit of the EVOM2 and the included STX2 electrode detect the confluence of the cellular monolayer. When combined with WPI’s Endohm chamber, the EVOM2 can also be used to perform more accurate quantitative measurements or lower resistance measurements like trans endothelial electrical resistance measurements.

The isolated power source of the EVOM2 was specifically designed to avoid adverse effects on tissue and the formation of electrode metal deposits, even when it is plugged into a standard wall outlet. Now, the EVOM2 is always on when you need it. In addition, its rechargeable battery allows up to 10 hours of mobile use. The four and a half digit readout provides a range of 1-9,999 Ω. The included test electrode lets you calibrate the resistance measurements for an accurate reading every time, and the voltage meter never needs calibration. An analog BNC output is standard with the EVOM2, providing an output port for recording data or remote display of the EVOM2 output.

EVOM2 comes complete with the popular STX2 “chopstick” electrodes, 4 mm wide and 1mm thick. Each stick of the electrode pair contains a silver/silver-chloride pellet for measuring voltage and a silver electrode for passing current. The small size of each electrode is designed to facilitate placement of the electrodes into a variety of standard cell culture wells.

Other Resources

JOVE video: Models and Methods to Evaluate Transport of Drug Delivery Systems Across Cellular Barriers. J. Vis. Exp. (80), e50638, doi:10.3791/50638 (2013) can be watched here.

 

VIDEO: Models and Methods to Evaluate Transport of Drug Delivery Systems Across Cellular Barriers

See how to use and EndOhm chamber with an EVOM2 meter. 


In this video Mike shows you how to equilibrate your STX electrodes.


In this video, you can learn how to test your EVOM2.


Cellular Confluency of Epithelial Cells

The original EVOM was featured in this application video.

Specifications

Available models

Part # Voltmeter Electrode Charger (800496)

Battery (91736)

1 kΩ Test Resistor (91750)
EVOM2 0-10 kΩ Range Epithelial Volt/Ohm Meter

STX2

(Basic Electrode)

Yes Yes (Installed) Yes
91799 0-10 kΩ Range Epithelial Volt/Ohm Meter

STX3

(Basic Adjustable Gap Electrode)

Yes Yes (Installed) Yes
300523 0-100 kΩ Range Epithelial Volt/Ohm Meter

STX2

 

(Basic Electrode)

Yes Yes (Installed) Yes

EVOM2 specifications

MEMBRANE VOLTAGE RANGE ±199.0 mV
VOLTAGE MEASUREMENT 0.1mV
RESISTANCE RANGES  0 to 9999 ohm
RESISTANCE RESOLUTION 1 ohm
AC SQUARE WAVE CURRENT ±10 µA at 12.5 Hz
POWER  Internal rechargeable 6V NiMH 2200 mAH battery with external 12VDC supply for recharging
SHIPPING WEIGHT 3 lb (1.4 Kg)
 ELECTRODE CONNECTION RJ-11 Connector (telephone style)
TEST RESISTOR External
ENVIRONMENTAL RANGE 10-38 C (50-100 F) 0 - 90% non-condensing relative humidity

 

Accessories

EVM-EL-03-03-01

EVM-EL-03-03-01

STX4 EVOM™ Electrode with Removable Blades for TEER in 6.5 mm Inserts

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STX100C

STX100C

DISCONTINUED - STX HTS EVOM™ Electrode for EVOM2, use with Corning Costar HTS ...

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STX100C96

STX100C96

DISCONTINUED - STX HTS EVOM™ Electrode for EVOM2, use with Corning HTS 96-Well...

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STX100F

STX100F

DISCONTINUED - STX HTS EVOM™ Electrode for EVOM2, use with Corning Falcon HTS ...

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STX100M

STX100M

DISCONTINUED - STX HTS EVOM™ Electrode for EVOM2, use with Millipore Multiscre...

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EVM-EL-03-01-03

EVM-EL-03-01-03

ENDOHM-24 EVOM™ Electrode for TEER in 24 mm Insert, for use with EVOM Manual a...

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EVM-EL-03-01-02

EVM-EL-03-01-02

ENDOHM-12 EVOM™ Electrode for TEER in 12 mm Insert, for use with EVOM Manual a...

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ENDOHM-6G

ENDOHM-6G

EndOhm for 6mm Culture Cups (24 wells per plate)

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STX2

STX2

Chopstick Electrode Set for EVOM2, 4mm

(Original Manufacture Direct Replacemen...

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STX3

STX3

Chopstick Electrode Set for EVOM2

(Original Manufacture Direct Replacement for...

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Citations

Chen, T., Dai, S., Li, X., Luo, P., Zhu, J., Wang, Y., … 2018, undefined. (n.d.). Sirt1-Sirt3 axis regulates human blood-brain barrier permeability in response to ischemia. Elsevier. Retrieved from https://www.sciencedirect.com/science/article/pii/S2213231717304561

Sebille, Y. Van, Gibson, R., cancer, H. W.-… journal of, & 2018, undefined. (n.d.). Dacomitinib-induced diarrhea: Targeting chloride secretion with crofelemer. Wiley Online Library. Retrieved from http://onlinelibrary.wiley.com/doi/10.1002/ijc.31048/full

Alexeev, E., Lanis, J., Kao, D., … E. C.-T. A. journal of, & 2018, undefined. (n.d.). Microbiota-Derived Indole Metabolites Promote Human and Murine Intestinal Homeostasis through Regulation of Interleukin-10 Receptor. Elsevier. Retrieved from https://www.sciencedirect.com/science/article/pii/S0002944017308751

Xiao, Y., Wu, J., Yuan, Y., … X. G.-M., & 2018, undefined. (n.d.). Effect of moesin phosphorylation on high-dose sphingosine-1-phosphate-induced endothelial responses. Spandidos-Publications.com. Retrieved from https://www.spandidos-publications.com/10.3892/mmr.2017.8029

Benthani, F., Herrmann, D., Tran, P., Oncogene, L. P.-, & 2018, undefined. (n.d.). “MCC”protein interacts with E-cadherin and β-catenin strengthening cell–cell adhesion of HCT116 colon cancer cells. Nature.com. Retrieved from https://www.nature.com/articles/onc2017362

Brewington, J., Backstrom, J., … A. F.-J., & 2018, undefined. (n.d.). Chronic β2AR stimulation limits CFTR activation in human airway epithelia. Am Soc Clin Investig. Retrieved from https://insight.jci.org/articles/view/93029

Ferreira, A., Santos, A., Falcão, A., Toxicology, G. A.-F. and C., & 2018, undefined. (n.d.). In vitro screening of dual flavonoid combinations for reversing P-glycoprotein-mediated multidrug resistance: Focus on antiepileptic drugs. Elsevier. Retrieved from https://www.sciencedirect.com/science/article/pii/S0278691517306622

Arnaud, C., Bouyon, S., … S. R.-J. of the, & 2018, undefined. (n.d.). Nonmuscle Myosin Light Chain Kinase: A Key Player in Intermittent Hypoxia-Induced Vascular Alterations. Am Heart Assoc. Retrieved from http://jaha.ahajournals.org/content/7/3/e007893.abstract

Shamsa, E., Mahjub, R., … M. M.-I. J. of, & 2018, undefined. (n.d.). Nanoparticles Prepared From N, N-Dimethyl-N-Octyl Chitosan as the Novel Approach for Oral Delivery of Insulin: Preparation, Statistical Optimization and. Ijpr.sbmu.ac.ir. Retrieved from http://ijpr.sbmu.ac.ir/article_2238_0.html

Robinson, B., Shaji, C., … A. L.-T. and I., & 2018, undefined. (n.d.). Measurement of Microvascular Endothelial Barrier Dysfunction and Hyperpermeability In Vitro. Springer. Retrieved from https://link.springer.com/protocol/10.1007/978-1-4939-7526-6_19

Robinson, B. D., Shaji, C. A., Lomas, A., & Tharakan, B. (2018). Measurement of Microvascular Endothelial Barrier Dysfunction and Hyperpermeability In Vitro (pp. 237–242). http://doi.org/10.1007/978-1-4939-7526-6_19

Van Sebille, Y. Z. A., Gibson, R. J., Wardill, H. R., Ball, I. A., Keefe, D. M. K., & Bowen, J. M. (2018). Dacomitinib-induced diarrhea: Targeting chloride secretion with crofelemer. International Journal of Cancer, 142(2), 369–380. http://doi.org/10.1002/ijc.31048

Curtis, V., Ehrentraut, S., & Campbell, E. (2015). Stabilization of HIF through inhibition of Cullin-2 neddylation is protective in mucosal inflammatory responses. The FASEB Journal. Retrieved from https://www.fasebj.org/content/29/1/208.short

Fiandra, L., Colombo, M., & Mazzucchelli, S. (2015). Nanoformulation of antiretroviral drugs enhances their penetration across the blood brain barrier in mice. … , Biology and Medicine. Retrieved from https://www.sciencedirect.com/science/article/pii/S1549963415000830

Hind, W., & Tufarelli, C. (2015). Endocannabinoids modulate human blood–brain barrier permeability in vitro. British Journal of …. Retrieved from https://onlinelibrary.wiley.com/doi/10.1111/bph.13106/full

Kiatprasert, P., & Deachapunya, C. (2015). Soy isoflavones improves endometrial barrier through tight junction gene expression. …. Retrieved from https://www.reproduction-online.org/content/149/3/269.short

Kim, H., Lee, K., Park, C., & Song, J. (2015). Polyhexamethylene guanidine phosphate aerosol particles induce pulmonary inflammatory and fibrotic responses. Archives of …. Retrieved from https://link.springer.com/article/10.1007/s00204-015-1486-9

Laffleur, F. (2015). Permeation Enhancement via Thiolation: In Vitro and Ex Vivo Evaluation of Hyaluronic Acid–Cysteine Ethyl Ester. Journal of Pharmaceutical …. Retrieved from https://onlinelibrary.wiley.com/doi/10.1002/jps.24456/full

Loma, P. (2015). Diadenosine tetraphosphate induces tight junction disassembly thus increasing corneal epithelial permeability. British Journal of …. Retrieved from https://onlinelibrary.wiley.com/doi/10.1111/bph.12972/full

Prasad, S., Sajja, R., Park, J., & Naik, P. (2015). Impact of cigarette smoke extract and hyperglycemic conditions on blood–brain barrier endothelial cells. Fluids and Barriers of …. Retrieved from https://link.springer.com/article/10.1186/s12987-015-0014-x

Schultz, I., & Vollmers, F. (2015). Pulmonary Insulin-like growth factor I delivery from trehalose and silk-fibroin microparticles. ACS Biomaterials …. Retrieved from https://pubs.acs.org/doi/abs/10.1021/ab500101c

Sobhani, H., Tarighi, P., & Ostad, S. (2015). Formulation Development and Toxicity Assessment of Triacetin Mediated Nanoemulsions as Novel Delivery Systems for Rapamycin. Iranian Journal of …. Retrieved from https://ijpr.sbmu.ac.ir/article_1708_75.html

Srimanee, A., Regberg, J., & Langel, Ü. (2015). Application of CPPs for Brain Delivery. Cell-Penetrating Peptides: Methods …. Retrieved from https://link.springer.com/protocol/10.1007/978-1-4939-2806-4_23

Willenberg, I., Elsner, L. von, Steinberg, P., & Schebb, N. (2015). Development of an online-SPE-LC-MS method for the investigation of the intestinal absorption of 2-amino-1-methyl-6-phenylimidazo pyridine (PHIP) and its. Food Chemistry. Retrieved from https://www.sciencedirect.com/science/article/pii/S0308814614009248

Willenberg, I., Michael, M., Wonik, J., & Bartel, L. (2015). Investigation of the absorption of resveratrol oligomers in the Caco-2 cellular model of intestinal absorption. Food Chemistry. Retrieved from https://www.sciencedirect.com/science/article/pii/S0308814614010012

Xing, F., Sharma, S., Liu, Y., Mo, Y., & Wu, K. (2015). miR-509 suppresses brain metastasis of breast cancer cells by modulating RhoC and TNF-α. Oncogene. Retrieved from https://www.nature.com/onc/journal/vaop/ncurrent/full/onc2014412a.html

Xu, Q., Liu, J., Wang, Z., Guo, X., Zhou, G., & Liu, Y. (2015). Heat Stress-Induced Disruption of Endothelial Barrier Function Is via PAR1 Signaling and Suppressed by Xuebijing Injection. PloS One. Retrieved from https://dx.plos.org/10.1371/journal.pone.0118057

Zhang, J., Ni, C., & Yang, Z. (2015). Specific binding of Clostridium perfringens enterotoxin fragment to Claudin-b and modulation of zebrafish epidermal barrier. Experimental …. Retrieved from https://onlinelibrary.wiley.com/doi/10.1111/exd.12728/full

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