Transition metal complexes as indicators for a fiber optic oxygen sensor

Painstaking spectrophotometric investigation was carried out on organo-metallic compounds in order to identify the most suitable one for the detection of oxygen. A bis(Histidinato)Cobalt(II) solution was chosen, characterized by an absorption change at ? = 408 nm as a function of the molecular oxygen concentration in the surrounding environment. An optical fiber system was developed, which makes use of a halogen lamp as the source and an appropriate electronic circuit as a detection system. The optrode is a very small hollow fiber membrane filled with the solution and coupled with optical fibers.