"Pericellular oxygen concentration is in a range that most would consider severe hypoxia, at <0.6% or about 4.6mm Hg, in the medium in 21% oxygen atmosphere."

70% of scientists surveyed recently by Nature were unable to reproduce another’s experiment, and a post-publication analysis has suggested a reproducibility rate of as little as 10% in cancer biology.

Dissolved oxygen concentration at the bottom of the flask reached zero during cell growth which indicates that mixing and mass transfer is not optimal for T-flask cultured cells. Despite these significant achievements, on-line monitoring of both DO and pH changes during cell passaging or subculturing in T-flasks and how they may affect cellular metabolism is not routine.