- high-resolution terminology - matching measurements at high-resolution
Cell count and normalization in HRR
Description
Cell count Nce is the number of cells, expressed in the unit [x] (1 Mx = 106 x). Normalization of respiratory rate by cell count yields oxygen flow IO2 expressed in units [amol·s-1·x-1] (=10-18 mol·s-1·x-1).
Abbreviation: Nce
Reference: BEC 2020.1 doi10.26124bec2020-0001.v1, Gnaiger 2020 MitoPathways
Communicated by Gnaiger Erich 2020-09-18
Cell count and cell concentration
Cell concentration from cell suspension to experimental chamber
- Table 1. Definition of terms, symbols and units.
Term Symbol = Definition Unit Comment Volume of cell suspension σ Vσ mL The symbol σ is used for 'suspension', distinguished from the symbol s for 'sample'. Frequently the sediment of cells obtained from centrifugation is re-suspended in the experimental medium (e.g. MiR05 plus pyruvate) to obtain Vσ. Cell count in Vσ Nce,σ = Cce,σ∙Vσ mL The total cell harvest available for respirometry and additional analyses of this sample of cells. Cell-count concentration in cell suspension Vσ Cce,σ = Nce,σ/Vσ mL Subsample from Vσ for cell counting Vσ→N mL For reliable normalization of respiration, Vσ→N should be equal or larger than 0.05 mL. Smaller volumes are taken as a subsample for counting, if the aim is merely to define a procedure of dilutions, with final subsamples taken after dilutions for cell-counting. Subsample from Vσ for respirometry J Vσ→J = Vσ-Vσ→N mL . Experimental chamber volume V mL Effective aqueous volume in the experimental system (2.0 mL or 0.5 mL) Experimental chamber volume + VStopper capillary V' = V+VStopper capillary mL 2.085 or 0.54 mL Experimental chamber volume + VStopper capillary + subsample volume V'' = V'+Vsubsamples mL Subsamples taken from the O2k chamber prior to closing the chamber. Cell-count in experimental chamber Nce = N·Uce x 106 x = 1 Mx Cell-count concentration in experimental chamber Cce = Nce/V Mx/mL 106 x/mL = 1 Mx/mL = 109 x/L = 1 Gx/L Volume of respirometric stock J VJ = Vs→J + ΔVJ mL
MitoPedia methods: Respirometry
MitoPedia O2k and high-resolution respirometry:
DatLab,
O2k-Respirometry,
O2k-FluoRespirometry
