Non-invasive & in-process monitoring

Sensor Spots

Flow-Through Cell

Dipping Probe

Biotechnology: Carbon Dioxide Monitoring in Process Development

In bioprocess development & production, monitoring dissolved CO₂ in addition to pH and O₂ provides valuable information. It ensures stress-free cultivation conditions during mammalian cell culture (e.g. CHO cell-line). Constant pH and / or oxygen supply and sufficient nutrition levels are key parameters to optimize yield. Thereby, excess CO₂ can act as a stressor or even a toxin to the culture and has to be controlled. The chemical optical CO₂ sensors can enhance performance of process monitoring during cultivation in disposables, leading to process optimization.

PreSens CO2 Sensors as an Alternative to Off-Line Sampling

PreSens CO₂ sensors were evaluated for monitoring the cultivation cells in a 3-L bioreactor. The sensors show excellent long-term stability over a period of 10 days during cell cultivation of CHO cells with an initial seed density of 400,000 cells/mL. The readings of the PreSens CO₂ sensor offer the possibility to continuously monitor the CO₂ concentration between two off-line measurements.
Rick Baggio, Millipore Corporation, Bedford, MA, USA, Poster Presentation at ESACT2009, Dublin

Medical Application: Online Monitoring of pCO₂

Online monitoring of blood pCO₂ is desirable in hypercapnia (pCO₂ > 45 mmHg) therapy during point-of-care treatment in intensive care units. During surgeries online monitoring of pCO₂ provides continuous fast and reliable information on patients' viability enabling faster clinical decision making compared to standard off-line laboratory analyses based methods. Chemical optical sensors and instrumentation can be integrated (OEM) to monitoring systems, like heart-lung machines, blood parameter control units or blood parameter monitors to provide information for fast clinical decision making.

Scientific: Carbon Dioxide Monitoring for Biological Applications

Increased CO₂ uptake from the atmosphere caused by anthropogenic sources is believed to cause ocean acidification, with not yet foreseeable effects on marine life and ecosystem. Monitoring pCO₂ in experimental set-ups simulating future levels of carbon dioxide can help to gain knowledge on the effects of ocean acidification on marine fauna. Besides the marine application, monitoring pCO₂ also allows knowledge to be gained on land-based plant physiology. Monitoring pCO₂ helps increasing yield during aquaculture of fish (fish farming) by providing convenient growth conditions. Excess carbon dioxide levels need to be monitored as this leads to hyperventilation of sea animals.

Dual Lifetime Referencing - An Internal Referencing Method

The chemical optical CO₂ sensor is based on our patented DLR measurement principle. The light of the blue LED excites the sensor to emit fluorescence. The luminescence lifetime measured is a superposition of the signals of an analyte sensitive indicator and an inert reference indicator, where both indicators exhibit very different luminescence lifetimes and the luminescence of the analytic sensitive indicator can be suppressed by CO₂. The measurement signal correlates to the partial pressure of carbon dioxide.