Cookies help us deliver our services. By using our services, you agree to our use of cookies. More information

Oxygen flux

From Bioblast
The printable version is no longer supported and may have rendering errors. Please update your browser bookmarks and please use the default browser print function instead.


high-resolution terminology - matching measurements at high-resolution


Oxygen flux

Description

Oxygen flux, JO2, is a specific quantity. Oxygen flux is oxygen flow, IO2 [mol·s-1 per system] (an extensive quantity), divided by system size. Flux may be volume-specific (flow per volume [pmol·s-1·mL-1]), mass-specific (flow per mass [pmol·s-1·mg-1]), or marker-specific (flow per mtEU). Oxygen flux (e.g., per body mass, or per cell volume) is distinguished from oxygen flow (per number of objects, such as cells), IO2 [mol·s-1·x-1]. These are different forms of normalization of rate.

Abbreviation: JO2

Reference: BEC 2020.1, Gnaiger 2020 BEC MitoPathways, Gnaiger 1993 Pure Appl Chem, Renner 2003 Biochim Biophys Acta

Contributed by Gnaiger E (2020-01-15)

Which SI units should be used?

  • The SI unit for volume
1000 L = 1 m3
1 L = 1 dm3
1 mL = 1 cm3
1 µL = 1 mm3
  • Convert various units of volume-specific oxygen flux, JO2, to SI units [nmol·s-1·L-1] = [pmol·s-1·mL-1]
1 µmol O2∙min-1∙L-1 ∙ [1000 nmol∙(1 µmol)-1] ∙ [1 min∙(60 s)-1] = 16.67 nmol O2∙s-1∙L-1
1 nmol O2∙min-1∙mL-1 ∙ [1000 pmol∙(1 nmol)-1] ∙ [1 min∙(60 s)-1] = 16.67 pmol O2∙s-1∙mL-1
1 nmol O2∙h-1∙mL-1 ∙ [1000 pmol∙(1 nmol)-1] ∙ [1 min∙(60 s)-1] ∙ [1 h∙(60 min)-1] = 0.2778 pmol O2∙s-1∙mL-1
1 natom O∙s-1∙L-1 ∙ [1 nmol O2∙(2 natm O)-1] = 0.5 nmol O2∙s-1∙L-1
1 natom O∙min-1∙L-1 ∙ [1000 pmol O2∙(2 natom O)-1] ∙ [1 min∙(60 s)-1] = 8.33 pmol O2∙s-1∙L-1
  • Convert VO2max/M from ergometric to SI units
1 mL O2∙min-1∙kg-1 (at STPD) ∙ [1000 µmol∙(22.392 mL)-1] ∙ [1 min∙(60 s)-1] = 0.744 µmol O2∙s-1∙kg-1
  • There is a difference between oxygen flux per volume and oxygen concentration change per time
The oxygen concentration change per time (= rate of concentration change) is expressed in units [µmol O2∙L-1∙s-1].
By definition the rate of concentration change is zero in an open system at steady-state, when the concentration in the system does not change at any respiratory flux by the sample enclosed in the open system.
Oxygen flux per volume (= volume-specific oxygen flux) is expressed in units [µmol O2∙s-1∙L-1] or [nmol O2∙s-1∙L-1]
By definition the volume-specific oxygen flux is the advancement of reaction per volume of the reaction chamber.
Oxygen flux per mass (= mass-specific oxygen flux) is expressed in units [µmol O2∙s-1∙kg-1] = [pmol O2∙s-1∙mg-1]
By definition the mass-specific oxygen flux is the advancement of reaction per mass of the sample enclosed in the reaction chamber.

References

Bioblast linkReferenceYear
Gnaiger E et al ― MitoEAGLE Task Group (2020) Mitochondrial physiology. Bioenerg Commun 2020.1. https://doi.org/10.26124/bec:2020-0001.v12020


Questions.jpg


Click to expand or collaps
Bioblast links: Normalization - >>>>>>> - Click on [Expand] or [Collapse] - >>>>>>>



MitoPedia concepts: MiP concept, Ergodynamics 


MitoPedia methods: Respirometry