pH, Oxygen and OUR Monitoring in Shake Flasks, Cultivation Tubes and T-flasks

SFR Shake Flask Reader

The SFR Shake Flask Reader monitors pH, oxygen and OUR in up to 9 Erlenmeyer flasks, cultivation tubes, or T-flasks simultaneously. It fits in nearly all standard shakers. Measurement data is transferred wirelessly via Bluetooth to your PC / notebook. The corresponding ready-to-use vessels contain pre-calibrated sensor spots. The system monitors non-invasively through the transparent bottom of the container. Different types and sizes of flasks and tubes are available. Plastic, disposable flasks contain pre-calibrated oxygen and pH sensors, while re-usable glass flasks are equipped with autoclavable oxygen sensors.

  • Fast monitoring of up to 63 shake flasks in parallel
  • For microbial and cell culture
  • Pre-calibrated cultivation vessels are ready-to-use
  • Compatible with standard shakers
  • Glass & plastic flasks in different sizes available
  • Non-invasive measurement
  • Used in seed train & bioprocess development
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Process Monitoring in Suspension-Adapted CHO Cell Cultures

The online measurement of dissolved oxygen concentration and pH in shaken bioreactors paves the way for proper scale down activities from bench-top stirred-tanks to smaller scales. Adjustment of shaking speed as a function of pO2 is now possible avoiding possible oxygen limitations at high cell densities. Even a simple pH readjustment by tuning the pCO2 in the incubator is feasible to optimize the output from simple experiments with shaken bioreactors.
Dr. Robert Puskeiler, Roche Diagnostics, Penzberg, Germany

Yeast & E. coli: Ensure Enough Oxygen Supply

S. cerevisiae grows on different sugars as carbon source. While growth on glucose and fructose is mainly fermentative, growth on galactose is mainly respirative. This leads to low oxygen concentration in the shake flasks. The accurately measured oxygen indicates the need to increase rotation frequency to avoid oxygen limitation.

High oxygen demand is typical for E. coli in its exponential phase. In the cultivation shown on the left, rotation speed had to be changed twice in order to avoid oxygen limitation. In addition, changes in the metabolism can be detected by measuring DO.

Schneider et al., University of Saarland, Saarbrücken, GermanyBioprocess Biosyst Eng., 33(5), 541 - 547, 2009


Specifications Oxygen pH*

* provided Sensor Flasks are used without further handling in physiological solutions
** at 100 rpm & in cell culture media

Measurement range 0 – 100 % O2 5.5 – 8.0 pH
Response time (t90) at 25 °C < 60 sec. < 60 sec.

± 0.01 % O2 at 0.21 % O2
± 0.1 % O2 at 20.9 % O2

± 0.01 pH at pH = 7**

± 0.05 % O2 at 0.2 % O2
± 0.4 % O2 at 20.9 % O2

± 0.1 pH at pH = 7 with one-point-adjustment

± 0.2 pH at pH = 7 with pre-calibration
Drift < 0.01 % O2 per day (sampling interval of 1 min.) < 0.01 pH per day (sampling interval of 1 min.)
Temperature range from + 5 °C to + 50 °C
Compatibility Aqueous solutions, ethanol (max. 10 % v/v), methanol (max. 10 % v/v), pH 2 - 4
Cross-sensitivity Typically no cross-sensitivity in culture media Reduced to ionic strength (salinity); a high concentration of small fluorescent molecules in the visible range can interfere
  Sensor flasks are delivered irradiated

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The Application of the SFR Shake Flask Reader in Teaching at the Esslingen University of Applied Sciences A New Method for Predicting Oxygen Supply during Aerobic Growth Characterization of Microbial Growth Profiles Insect Cell Cultivation in Orbitally Shaken Flasks with Sensors Accurate Insight into Oxygen Content of Shake Cultures Development of a Partly Controllable System at Shake Flask Scale Development of a Shaken Scale-Down Model Online Monitoring of Glucose, pH, and DO in Shake Flask Culture Design of Experiment (DoE) for Fed-batch Process Development in Shaken Cultures Investigation on ATP Synthesis via Oxidative Phosphorylation in C. glutamicum kLa Measurement in TubeSpin Bioreactors Continuous optical in-line glucose monitoring and control in CHO cultures contributes to enhanced metabolic efficiency while maintaining darbepoetin alfa product quality Phosphate limitation alleviates the inhibitory effect of manganese on itaconic acid production by Aspergillus terreus High cell density cultivation of E. coli in shake flasks for the production of recombinant proteins Robustness and Plasticity of Metabolic Pathway Flux among Uropathogenic Isolates of Pseudomonas aeruginosa HEK293 Cell-Based Bioprocess Development at Bench Scale by Means of Online Monitoring in Shake Flasks (RAMOS and SFR) Antifoam addition to shake flask cultures of recombinant Pichia pastoris increases yield The metabolic potential of Escherichia coli BL21 in defined and rich medium Optical device for parallel online measurement of dissolved oxygen and pH in shake flask cultures A shaken disposable bioreactor system for controlled insect cell cultivations at milliliter-scale Effects of hypoxic culture conditions on umbilical cord-derived human mesenchymal stem cells Conversion of Corynebacterium glutamicum from an aerobic respiring to an aerobic fermenting bacterium by inactivation of the respiratory chain Oxygen supply in disposable shake-flasks: prediciton of oxygen transfer rate, oxygen saturation and maximum cell concentration during aerobic growth


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Calibration Data


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