Specific oxygen consumption in mammalian cell culture: what is the typical per-cell rate range (qO2) expressed as pmol O2 per cell per hour?

Introduction / Context:
The specific oxygen consumption rate (qO2) is critical for sizing aeration, agitation, and oxygen transfer in bioreactors. Mammalian cells consume far less oxygen per cell than microbes, so correct units and magnitudes matter in process design.

Given Data / Assumptions:

• Mammalian qO2 values are very small on a per-cell basis.
• Reasonable design ranges are in picomoles O2 per cell per hour.
• nmol-per-cell values would be unrealistically high.

Concept / Approach:
Choose the range that fits literature-reported per-cell consumption. Values around 0.05–5 pmol O2/cell/h encompass many cell lines and physiological states, providing a practical order of magnitude for engineering calculations.

Step-by-Step Solution:

Verification / Alternative check:
Back-of-the-envelope calculations for common viable cell densities (10^6–10^7 cells/mL) with this qO2 range align with measured oxygen transfer capacities in mammalian bioreactors.

Why Other Options Are Wrong:

• A/B/E: nmol or mmol per cell per hour are far too high and physiologically implausible.
• D: The upper half overlaps but omits the lower portion commonly seen; the broader 0.05–5 pmol range is standard.

Common Pitfalls:
Mistaking per-cell rates for per-culture or per-mL rates; mixing up pmol and nmol units.

Final Answer:
0.05–5 pmol O2/cell/h