Selected Probes
Oxygen Probe for In-line Measurement
The oxygen probe for in-line measurement (OIM) consists of a fitting made of stainless steel with an optical exchange cap (OEC). The OEC is screwed to the top of the metal fitting. The OIM is connected to the instrument via an optical fiber. The OIM has a standardized thread and length and is compatible with most bioreactors and port adapters. In addition, customized fittings for e. g. sight glasses are offered.
Oxygen Dipping Probe
The Oxygen Dipping Probe consists of a polymer optical fiber with a polished distal tip which is coated with a planar oxygen-sensitive foil.
The end of the polymer optical fiber is covered with a high-grade steel tube to protect both the sensor material and the optical fiber. The steel tube has an outer diameter of 4 mm and a length of 10 cm. The diameter of the fiber itself is 2 mm.
Due to the use of a polymer optical fiber, this probe is not compatible to temperatures higher than 70°C.
The Smart Measurement Method
The light from the blue-green LED excites the oxygen sensor to emit fluorescence. If the sensor spot encounters an oxygen molecule, the excess energy is transferred to the oxygen molecule in a non-radiative transfer, decreasing or quenching the fluorescence signal. The degree of quenching correlates to the partial pressure of oxygen in the matrix, which is in dynamic equilibrium with oxygen in the sample. The decay time measurement is internally referenced.