Optical Oxygen and pH Sensors
Dec 2011Ocean Optics Inc.Request Info
DUNEDIN, Fla., Dec. 12, 2011 — For monitoring of food and fermentation processes, Ocean Optics Inc. has unveiled optical oxygen and pH sensors. Advances in sensor materials and optoelectronics have enabled new optical sensors for use in life sciences, pharmaceuticals, biotechnology, and food and beverage processing. Compared with traditional electrochemical sensing techniques such as galvanic sensors, these optical sensors can be made small and customizable, and they perform nonintrusive real-time measurements.
The fiber optic sensors are designed for accurate in situ measurements in various media. Proprietary sensor coating materials do not consume the sample and can be applied to substrates such as probes, self-adhesive acrylic patches and microtiter wells. Coating options are available for general lab use, food processing lines and hydrocarbon-rich environments. Depending upon the application, oxygen presence or pH can be visually determined by color change with a handheld LED, or a fluorometer can be used to make exact measurements.
The principle of operation is to trap an oxygen-sensitive fluorophore or pH indicator dye in a sol-gel host matrix that can be applied to the tip of a fiber, an adhesive membrane such as a patch or a flat substrate such as a cuvette. The indicator materials change optical properties in response to specific analytes in their immediate environment, and electronics then measure the response. For oxygen, the NeoFox phase fluorometer measures the partial pressure of dissolved or gaseous oxygen; for pH, a miniature fiber optic spectrometer measures the colorimetric (absorbance) response of the pH dye.
The company says that its optical oxygen and pH patches overcome the limitations of electrochemical-based oxygen and pH sensing. They can be integrated within a small-scale biosystem such as a bioflask used for fermentation, and they provide continuous, nonintrusive monitoring of key system parameters.
The ability to monitor dissolved oxygen and pH in real time without perturbing a sealed environment can lead to an improved understanding of the processes in the bioreactor and help to facilitate the development of biological products and fermentation processes.