WPI EVOM - Introduction; EVOM Manual Features

4 World Precision Instruments
INTRODUCTION
EVOM™ Manual is the WPI’s manual instrument for measuring Trans Epithelial
Electrical Resistance (TEER). The EVOM™ Manual has been engineered to facilitate
ease of accurate, repeatable measurements and transfer of data. You no longer need
to log data by hand. The resistance or voltage information is written to a USB drive
in a format (CSV) that can be opened by most spreadsheet programs on either PC
or Mac. The processor controlled instrument is more stable and accurate. Included
is a footswitch for quick hands-free recording to the USB ash drive. The touch
screen interface is easy to use and setup for setting control wells in resistance or
voltage modes and measurements. The auto ranging resistance feature allows for
fast resistance measurements, and an overrange display feature ensures no false
readings. The EVOM™ Manual now has adjustable current levels in three xed ranges
with two lower ranges for sensitive membranes and high resistance ranges up to
100KΩ.
Conuence of a cellular monolayer is determined by an increase or a plateau in tissue
resistance detected using the unique electronic circuit of the EVOM™ Manual and the
EVOM™ STX4 electrode. The EVOM™ Manual qualitatively measures cell monolayer
health and quantitatively measures cell conuence. The EVOM™ Manual produces
a low AC current that avoids electrode metal deposits and adverse eects on tissues
which can otherwise be caused by higher DC currents. The EVOM™ Manual uses
low current and voltages and is designed for non-destructive testing for epithelial
monolayer conuence in cell cultures. In addition, resistance readings are unaected
by membrane capacitance or membrane voltage. The accuracy and repeatability of
the EVOM™ Manual system makes this instrument ideal for permeability, potential
dierence (PD) and other detailed membrane studies.
EVOM™ Manual Features
• Low noise design oers greater resolution and accuracy
• Automatic 20X sample averaging improves accuracy and stability
• Adjustable xed measurement currents (2, 4 or 10 μA)
• Resistance auto ranging from 1 Ω to 100,000 Ω or with three xed current ranges
• Reliable low current, low voltage design prevents metal ion transport
• Fast resistance stabilization on low levels under 200 Ω with resolution to 0.1 Ω
• Ergonomic tilt stand for low glare operation
• Graphical display of popular plates (6, 12, 24, 96) for trend analysis
• Display shows the most recent set of parameters
• Automatic plate indexing operation with or without control well subtraction for
resistance and potential dierence (PD) measurements
• Continuous data logging via USB (PC, Mac, Linux)
• Saves date stamped data to a spreadsheet readable le on a USB drive
• Upgradable rmware
• Secure data transfer to PC via the EVOM™ Companion Application