World Precision Instruments

Search the site by KEYWORD


Quick Finder


Testimonials

Researcher UCL, Institute of Ophthalmology

I am really impressed by your very high level of customer service. I got a problem of our pump recently and contacted the service. Julian Williams replied me immediately and tried to resolve the issue with good suggestions. Meanwhile, she loaned me a pump which enabled me to carry out my experime...
read more

Home  >   > ENDOHM-12G
ENDOHM-12G

ENDOHM-12G

EndOhm for 12mm Culture Cups (12 wells per plate)



Choose Quantity
  • Overview
  • Specifications
  • Accessories
  • Citations
  • Related Products

Overview

There are 2 images available to view - click to enlarge and scroll through the product gallery.

Endohm Instruction Manual
/ Download as PDF

For TEER measurement of epithelial and endothelial cell cultures

 

  • The new EndOhm chamber upper mount is made of polycarbonate and unaffected by alcohol
  • The glass chamber is easier to clean and more crack resistant than the prior version
  • Compatible with original EVOM, EVOM2™ EVOM3 meters
  • Adjustable apical electrode height
  • Crystal clear glass chamber allows visualization of apical electrode positioning
  • New insert holder with 120º tri-supports for three leg inserts
  • Three sizes cover a range of well cup sizes from a variety of manufacturers

Options

Part # Description
ENDOHM-24G-SNAP EndOhm for 24mm and Costar Snapwell Culture Cups (6 wells per plate)
ENDOHM-12G EndOhm for 12mm Culture Cups (12 wells per plate)
ENDOHM-6G EndOhm for 6mm Culture Cups (24 wells per plate)


Benefits

  • Stability and reproducibility superior to the STX2 electrodes to 1% tolerance
  • Can be used with 6, 12 or 24 well plates with removable inserts
  • Symmetrical electrode pattern disperses test current uniformly
  • Tri-leg supports offer mechanical stability and the membrane is held parallel to the electrodes (G version)
  • Simple test procedure to verify electrode performance

Applications

  • TEER measurement for removable culture cup systems using EVOM2™ meters for endothelial and epithelial cell cultures

TEER measurement in individual cups

Using WPI’s EVOM2™ resistance meter, Endohm chambers provide reproducible resistance measurements of endothelial and epithelial monolayers 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 height of the top electrode can be adjusted to fit cell culture cups of different manufacture.

Make more precise measurements with Endohms

Endohm’s symmetrically opposing circular disc electrodes, situated above and beneath the membrane, allow a more uniform current density to flow across the membrane than with STX2 electrodes. The background resistance of a blank insert is reduced from 150?Ω (when using WPI’s hand-held STX2 electrodes) to less than 5 Ω. With Endohm’s fixed electrode geometry, variation of readings on a given sample is reduced from 10-30 Ω with STX2 electrodes (depending on the experience of the user) to 1-2 Ω. Compared with other resistance measurement methods, Endohm with EVOM2™ offers a much more convenient and economic solution to “leaky tissue” measurement. Because of the uniform density of the AC square wave current from EVOM2™, errors owing to electrode polarization or membrane capacitance are largely eliminated. Endohm together with EVOM2™ offers the most accurate and economical endothelial ohmmeter now available. To date, cups from Corning, Millipore, Nunc, Greiner and BD Falcon have been tested. Endohm chambers may be sterilized with EtO, alcohol or a bactericide; not autoclavable.

 

 

Specifications

Compatibility Charts

 

The ENDOHM-12G is compatible with the following chambers:

Corning Millipore Membrane Diameter (mm) Growth Surface Area (cm²) Membrane Pore Size (μm)
3401   12  1.12 0.4
3402 PITP01250 12   1.12 3.0
3403 PITT01250 12   1.12 3.0
3493   12 1.12 0.4
3494   12 1.12 3.0
3460 PIHT15R48*
PET Insert
12 1.12 0.4
  PIRP15R48*
PET Insert
12 1.12 1.0
3462 PISP15R48*
PET Insert
12 1.12 3.0
  PIMP15R48*
PET Insert
12 1.12 5.0
  PIEP30R48*
PIEP15R48*
PET Insert
12 1.12 8.0

* The tri-supports legs must be balance correctly so that the filter is parallel to the electrodes.

Nunc Pore size (μm) Culture area (cm²)
140652 0.4 1.13
140654 3.0 1.13
140656 8.0 1.13

 

ThinCertTM Membrane material Pore size [µm] Pore density [cm-2] Optical membrane properties TC surface treatment/Sterile Multiwell plates/ThinCertTM per box
665640 PET 0.4 1 x 108 translucent +/+ 4/48
665641 PET 0.4  2 x 106 transparent +/+ 4/48
665610 PET 1.0  2 x 106 transparent +/+ 4/48
665630 PET 3.0  0.6  x 106 transparent +/+ 4/48
665631 PET 3.0  2 x 106 translucent +/+ 4/48
665638 PET 8.0  0.15 x 106 translucent +/+ 4/48

 

Millicell Pore size (μm) Qty/pk
MCHT12H48 0.4 48
MCRP12H48 1.0 48
MCSP12H48 3.0 48
MCMP12H48 5.0 48
MCEP12H48 8.0 48

 

BD Falcon Membrane material Pore size [µm] Pore density [cm-2] Optical membrane properties TC plate (#wells)
353180 PET 0.4 2.0 ± 0.2 x 106 transparent 12
353103 PET 1.0 1.6 ± 0.6 x 106 transparent 12
353181 PET 3.0 8 ± 2 x 105 transparent 12
353182 PET 8.0 6 ± 2 x 104 translucent 12
353494 PET 0.4HD 100 ± 10 x 106 translucent 12
353292 PET 3.0HD 2.0 ± 0.2 x 105 translucent 12

Accessories

Citations

Sheller, R. A., Cuevas, M. E., & Todd, M. C. (2017). Comparison of transepithelial resistance measurement techniques: Chopsticks vs. Endohm. Biological Procedures Online, 19, 4. http://doi.org/10.1186/s12575-017-0053-6

Srinivasan, B., Kolli, A. R., Esch, M. B., Abaci, H. E., Shuler, M. L., & Hickman, J. J. (2015). TEER measurement techniques for in vitro barrier model systems. Journal of Laboratory Automation, 20(2), 107–26. http://doi.org/10.1177/2211068214561025

TORRES, R., PIZARRO, L., CSENDES, A., GARCÍA, C., LAGOS, N., Pasdar, M., … Roskelley, C. (2007). GTX 2/3 EPIMERS PERMEATE THE INTESTINE THROUGH A PARACELLULAR PATHWAY. The Journal of Toxicological Sciences, 32(3), 241–248. http://doi.org/10.2131/jts.32.241

Patil, R. V., Han, Z., Yiming, M., Yang, J., Iserovich, P., Wax, M. B., & Fischbarg, J. (2001). Fluid transport by human nonpigmented ciliary epithelial layers in culture: a homeostatic role for aquaporin-1. American Journal of Physiology - Cell Physiology, 281(4).

RelatedItems

Our Clients Include:

GlaxoSmithKline
University College London
Novartis
Imperial College
University of Cambridge
University of Oxford

Keep in Touch

We promise NEVER to share your details with anyone. You can opt out at any time.