The Petaka DO-Sense with O2 sensor Integrates all advantages of the Petaka LOT and Petaka-ET with the precision of the advance Dissolved Oxygen Monitoring technology of Ocean Optics, Inc. PetakaG3 DO-Sense has a fluorescent Oxygen minisensor of approximately 4 mm in diameter built inside (RedEye® Oxygen Patches with the FOXY coating). The sensor has an insignificant thickness which does not affect cell growth and expansion. This sensor allows either continuous or intermittent readings of the DO levels in the cell culture media across unlimited time span, in a non-intrusive manner. The Petaka G3 DO-Sense oxygen-sensitive fluorescent probe makes possible non invasive monitoring of cellular oxygen consumption avoiding the necessity of sampling. This external sensor-reading procedure allows rapid and specific detection of cellular oxygen consumption providing a direct sensitive means of assessing the impact of a given experimental condition on cellular metabolism.