O2k-Open Support alert

O2k-Open Support alert - 2024

Currently Answered Questions from the »Oroboros Ecosystem Agenda«

Sep 2024

Sep-24 Tu

The oxygen concentration is unusually high or low when starting a new measurement?

When starting a new measurement, the oxygen concentration is calculated by DatLab based on the default values or the most recently applied air calibration. If the temperature, barometric pressure, or solubility factor differ between the actual measurement and the default settings or the most recently performed and applied air calibration, the calculated oxygen concentration can be very different from the actual oxygen concentration.
- »Oxygen signal«
- communicated by »Schmitt Sabine« and »Willis Jaime R«

Sep-19 Th

"When working at low oxygen levels it is recommended to measure R0 before and after each measurement using the experimental sample for zero calibration."

- »MiPNet06.03 POS-calibration-SOP«
- communicated by »Baglivo Eleonora« and »Leo Elettra«

Sep-05 Th

"In the presence of high catalase activity, hydrogen peroxide, H₂O₂, is titrated into the O2k-chamber to increase oxygen levels"

- »MiPNet14.13 Medium-MiR06«
- communicated by »Cardoso Luiza« and »Baglivo Eleonora«

Aug 2024

Aug-22 Th

"Once a polarization voltage higher than 0 mV is selected and applied [in ‘Start measurement’ or ‘O2k Control (active)’ window], the LED of the Fluo sensor lights up."

- »MiPNet28.09 O2k-Fluo Smart-Module manual«
- communicated by »Grings Mateus« and »Cardoso Luiza«

Aug-19 Mo

Do I need to measure muscle tissue respirometry immediately after the biopsy?

No, the sample can be stored in ice-cold BIOPS solution at 0 °C for several hours, depending on the source of muscle tissue.
- »MiPNet14.14 PermeabilizedFiberPreparation«
- communicated by »Willis Jaime R« and »Timon-Gomez Alba«

Aug-08 Th

"Instrumental background tests should cover the entire experimental oxygen range."

- »MiPNet14.06 Instrumental O2 Background«
- communicated by »Schmitt Sabine« and »Baglivo Eleonora«

Aug-05 Mo

How do I ship my O2k?

To avoid any damage, the O2k-Main Unit must be shipped without O2k-chambers and POS in the Packing\O2k-Box 1, as only this packing material provides sufficient protection during transport. Be sure to follow the general packing instructions.
- »Shipping an O2k«
- communicated by »Timon-Gomez Alba« and »Grings Mateus«

Jul 2024

Jul-25 Th

"Oxia generates gaseous oxygen and hydrogen (...) used to control the O₂ regime in the Oroboros O2k"

- »MiPNet26.14_Oxia«
- communicated by »Cardoso Luiza« and »Schmitt Sabine«

Jul-22 Mo

Do you know how to export data points from your DatLab files?

Export all information and events from selected plots to a text file (*.csv) for further use in Excel and other programs compatible with .csv extension.
- »Export as CSV - DatLab«
- communicated by »Baglivo Eleonora« and »Grings Mateus«

Jul-11 Th

Cyclic voltammetry (CV) is a type of electrochemical measurement, applied as a quality control step to (1) determine the redox potentials of coenzyme Q2, (2) check the quality of the Q-sensor, and (3) test the interference of chemicals used in the HRR assay with the Q-sensor.

- »MiPNet24.16 DatLab8.0: CV-Module«
- communicated by »Leo Elettra« and »Baglivo Eleonora«

Jul-08 Mo

How do you avoid clogged Hamilton syringes?

Perform cleaning cycles immediately after use to avoid precipitate formation, especially with syringes used for ADP (with MgCl₂) and fatty acids. In case of clogged syringes, follow the recommendations in the MiPNet below.
- »MiPNet19.14 SOP Hamilton microsyringes«
- communicated by »Grings Mateus« and »Timon-Gomez Alba«

Jun 2024

Jun-27 Th

NAD-redox ratios are expressed as the reduced NADH-fraction. The reduced NADH-fraction is calibrated for minimum and maximum NADH fluorescence values, which correspond to the fully oxidized and fully reduced states of the NAD pool, respectively.

- »MiPNet26.12_NextGen-O2k:_NADH-Module«
- communicated by »Leo Elettra« and »Grings Mateus«

Jun-24 Mo

Maintain a record of measurement information using the experimental log of your DatLab file.

The experimental log is generated for each measurement and provides detailed information about the experimental run that can be saved as PDF or printed for quality control.
- »Experimental log - DatLab«
- communicated by »Baglivo Eleonora« and »Grings Mateus«

Jun-13 Th

The glassy carbon and platinum electrode of the Q-sensor are tightly built-in into the Q-Stopper and need to be polished and cleaned before each experiment.

- »MiPNet24.12_NextGen-O2k:_Q-Module«
- communicated by »Schmitt Sabine« and »Cardoso Luiza«

Jun-10 Mo

The oxygen signal is a flatline?

If there is no response of the oxygen signal after the stirrer test or titration of dithionite, the raw signal might be at the detection limit. Check the raw signal, which should be between 1 and 3 µA at air saturation, at 25-37 °C and with a gain of 1.
- »Oxygen_signal«
- communicated by »Schmitt Sabine« and »Willis Jaime R«

May 2024

May-30 Th

"Harmonization of isolation protocols yielding intact and enzymatically active mitochondria are critical to assess mitochondrial respiratory function"

- »MiPNet20.06 Isolation mouse heart mitochondria«
- communicated by »Cardoso Luiza« and »Leo Elettra«

May-27 Mo

Same experimental conditions, but different O₂ fluxes in the left and right chambers?

Check for instrumental and operational factors that could be causing O₂ flux differences between the O2k-chambers.
- »Different O2 fluxes in left and right chamber«
- communicated by »Timon-Gomez Alba« and »Baglivo Eleonora«

May-16 Th

"The sample holder protects (...) fragile samples from potential damage caused by stirring the medium."

- »MiPNet27.07 Sample Holder«
- communicated by »Willis Jaime R« and »Timon-Gomez Alba«

May-13 Mo

Do you see fluctuations of O₂ slope negative following a pattern similar to the Peltier power, but without block temperature variation?

Placing the O2k under direct airflow of an air conditioning equipment may lead to disturbances in the O₂ slope negative.
- »Fluctuations of O₂ slope negative«
- communicated by »Cardoso Luiza« and »Grings Mateus«

May-02 Th

"In respirometric studies on blood cells, the purity of cell preparation should always be emphasized and documented."

- »MiPNet21.17 BloodCellsIsolation«
- communicated by »Timon-Gomez Alba« and »Baglivo Eleonora«

Apr 2024

Apr-29 Mo

How can I update DatLab 8 to the latest version?

If your computer with DatLab 8 is connected to the internet, go to “Check for updates” in the Help menu of DatLab 8, and follow the simple installation instructions.
- »Updating - DatLab«, »DatLab 8«
- communicated by »Leo Elettra« and »Baglivo Eleonora«

Apr-18 Th

How to store the POS overnight and up to several months?

Fill the chamber and the receptacle of the loosely inserted stopper with 70 % EtOH, add the Cover-slip and switch off the O2K.
- »MiPNet19.03 O2k-cleaning and ISS«
- communicated by »Leo Elettra« and »Grings Mateus«

Apr-15 Mo

Do you observe either a zero or low raw O₂ signal when starting a measurement?

Perform a test to evaluate whether this is related to an improperly positioned chamber or a faulty connection between the OroboPOS and the OroboPOS-Connector.
- »Oxygen signal«
- communicated by »Grings Mateus« and »Schmitt Sabine«

Apr-04 Th

Why is it important to check the H₂O₂ sensitivity when conducting an Amplex UltraRed (AmR) assay?

The sensitivity is influenced by experimental time, medium composition, added chemicals and sample, requiring multiple H₂O₂ calibrations throughout the measurement. After the initial AmR calibration, ensure that the sensitivity is within the recommended range.

- »MiPNet24.10 H2O2 flux analysis«, »Amplex UltraRed«
- communicated by »Grings Mateus« and »Schmitt Sabine«

Mar 2024

Mar-21 Th

How well do you handle your Hamilton syringes? What is a cleaning cycle?

"A syringe cleaning cycle consists of (1) filling an empty syringe with a washing solution while immersing [both the needle and] the base of the barrel into the washing solution, without fully removing the plunger, and (2) emptying the syringe into the waste beaker."
- »MiPNet19.14 SOP Hamilton microsyringes«
- communicated by »Baglivo Eleonora« and »Timon-Gomez Alba«

Mar-20 We

What if Alert: Error in titrations! appears in your O2 analysis template file?

The O2 analysis template recognizes discrepancies between the protocol selected in the first tab and the imported marks. Check the titration sequence and mark names against the protocol copied from the DLD file.
- »O₂ flux analysis«
- communicated by »Timon-Gomez Alba« and »Leo Elettra«

Mar-07 Th

Which medium can be used for the instrumental background test?

When using dithionite, the instrumental background test should be performed in mitochondrial respiration medium MiR05, MiR05-Kit or MiR06; or alternatively, in a strong alkaline phosphate buffer (>100 mM; >pH 8), to avoid side reactions that might interfere with the test.
- »MiPNet14.06_Instrumental_O2_background«
- communicated by »Schmitt Sabine« and »Timon-Gomez Alba«

Mar-04 Mo

Do you observe an unstable O₂ slope negative following TIP2k titrations during an instrumental O₂ background test?

Incorrect placement of TIP2k Filter Papers can lead to liquid accumulation and convective oxygen backdiffusion. Check for proper placement by confirming they are fully in contact with the stopper receptacle.
- »Instrumental O₂ background«, »Unstable O₂ slope negative«
- communicated by »Grings Mateus« and »Baglivo Eleonora«

Feb 2024

Feb-22 Th

What to do if the glass of the O2k-chamber starts to become opaque?

"Turbidity on the glass wall may be caused by precipitated protein. Remove the chambers from the O2k and with the O2k-stirrers removed, immerse in a beaker filled with HCl (10 M) overnight under a hood."
-»MiPNet19.03_O2k-cleaning_and_ISS«
- communicated by »Cardoso Luiza« and »Leo Elettra«

Feb-08 Th

Can I use the same stock solutions for all reagents for different O2k-chamber volumes?

"For some reagents, the concentration of the stock solution differs between the 2.0-mL and the 0.5-mL chamber (O2k-sV-Module) to facilitate a precise volume titration."
-»MiPNet09.12 O2k-Titrations«
- communicated by »Timon-Gomez Alba« and »Leo Elettra«

Jan 2024

Jan-25 Th

How do I view and change the settings of a measurement/file in DatLab 8?

"O2k control (active) will always show the settings of the active recording [and allow changes], while O2k info (view) will show the settings of the recorded selected file."

-»MiPNet28.07 NextGen-O2k Series XB manual«; »MiPNet28.08 Oroboros O2k Series J manual«
- communicated by »Baglivo Eleonora« and »Grings Mateus«

Jan-11 Th

What are special features of the new SmartPOS (O2k-Series J and NextGen-O2k-Series XB)?

- "The electrical connections of the SmartPOS are protected thus there is no need to clean them."
- "The serial number of the SmartPOS is automatically recognized by the DatLab 8 software."

»MiPNet28.10 SmartPOS-service«
- communicated by »Grings Mateus« and »Baglivo Eleonora«

Jan-08 Mo

Do you need to export DatLab traces for your publication?

Save your graph as an editable picture using "Copy to clipboard" in DatLab 7.4 (.wmf) or "Save" in DatLab 8 (.svg).
- »Copy to clipboard in DatLab 7«, »Download DatLab 8«
- communicated by »Baglivo Eleonora« and »Grings Mateus«