How to correctly perform a One Point Adjustment (OPA) with PhoxyPlates?

The One Point Adjustment (OPA) allows to adapt the general plate calibration data for certain influences of the sample/media (e.g. by sample color, temperature, specific media components, etc.) on the calibration data and to minimize well-to-well differences.

This OPA acts like a tara on scales and adapts the general calibration data set for each specific well or sensor position accordingly.

You can set a specific OPA value for O₂ and pH prior for applying OPA.

Example protocol:

• Take plate out of its packaging
• Fill all wells with plain buffer or media (with a known pH and/or oxygen saturation) that you want to use in the respective experiment.
• Place plate onto PhoxyCube in the incubator and let sample get into temperature equilibrium with the incubator conditions. The temperature can influence the sensor response. (The time needed to reach a temperature equilibrium can strongly depend on the used incubator and temperature. From our experience it may vary between 20 mins and several hours. Keeping the incubator door closed will help reaching the equilibrium faster)
• During that equilibration time you can set up the settings for the experiment, such as perform the Autodetect centers and Autoexposure, enter and save Calibration Values, Comment your experiment, set Measuring Interval, define Well Group layout.
• A tip for making the process more straightforward: if you use a soaking liquid with a defined known pH, you can combine the pH sensor pre-soaking activation phase with the temperature adaption, so that you can directly perform the one point adjustment (OPA) after that soaking period.
• Perform OPA
• Exchange liquid with sample and place plate back on PhoxyCube
• Start measurement.