Teer Calculations; Appendix E: Frequently Asked Questions - WPI EVOM Manual Instruction Manual

= 670 Ω * 3.14* 3.25* 3.25 / 100
= 670 Ω * 0.331 cm
= 221.77 Ω-cm .
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221.77 Ω is the resistance of a unit area of 1 cm
The larger the membrane, the lower the resistance. The dimension is Ω-cm

TEER Calculations

TEER is a normalized value of resistance per 1 square centimeter of unit area. To
compute TEER, multiply the measured resistance by the surface area's listed below.
For example, a 6.6 mm insert measures 1707 Ω, the TEER is 1707 Ω * 0.331 or 565 Ω.
• 6 well plate (24 mm inserts) 4.53 cm
• 12 well plate (12 mm inserts) 1.13 cm
• 24 well plate (6.5 mm inserts) 0.3316 cm
• 96 well plate (4.3 mm inserts) 0.145 cm

APPENDIX E: FREQUENTLY ASKED QUESTIONS

1. When do researchers want to use the blank function?
Answer: The blank function allows researchers to subtract out resistance
measurement that is not caused by the cell layer. This could be a reading affected
by the electrodes or fluid resistances or other factors. Normally, you would
measure a blank insert with the same volumes as the insert and keep subtracting
that blank value from the samples. This way, any offset contributed by the
electrode is nullified. The subtracted value is the resistance contributed by the
cellular layer.
3. Does the system automatically calculate TEER?
Answer: No. Calculating TEER requires an area calculation. See "TEER Calculations"
on page 2 and "Appendix D: Resistance Calculations" on page 36.)
4. The program is automatically stored when the last well is reached. What happens
when I only want to measure 8 of 96 wells and store the program?
Answer: Once you're done measuring, open the settings, press the store screen
menu, then store the plate data to the USB.
World Precision Instruments
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(TEER).
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EVOM™ Manual
, not Ω / cm
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