How to Chloride EVOM™ Auto GxP Electrodes

WPI’s EVOM™ line of transepithelial electrical resistance (TEER) measurement systems use silver-silver chloride electrodes for taking measurements. Our newest automated TEER measurement unit, the EVOM™ Auto, is available with an optional GxP module to ensure 21 CFR Part 11 compliance. GxP represents the quality guidelines in place to ensure standards are met. It is used for protocols like Good Laboratory Practice, Good Pharmaceutical Practice, Good Clinical Practice, Good Manufacturing Practice, and Good Research Practice.

Regular maintenance keeps your EVOM™ Auto GxP electrodes performing optimally. Periodically, you will need to re-chloride your electrodes. Just follow the steps shown in this video.

1. Select Maintenance from the main menu. The Maintenance window appears
2. To chloride, press the + or – buttons to set the timer to the desired time in minutes in the Chloridize frame
3. Select the radio button for the rinse station containing the chloriding solution
4. Fill the appropriate rinse station with a bleach solution
5. Press the Start Timer button. The Start Chloridize popup displays. Enter your comment and your EVOM™ Auto GxP Client password. If you don’t want to add a comment, you may select the No Comment checkbox. If you do, default text appears in the comment line. Then, press the Start button. The time interval displays on the counter in the center of the window. The title changes to Chloriding Time Remaining
6. The electrode array moves to the selected rinse station, and the counters start counting down to zero
7. When the count reaches zero, the electrode array retracts
8. At any point, you may stop the counter by pressing the Stop Timer button. This resets the counter to zero and retracts the electrode array