Development of a medical fiber-optic oxygen sensor based on optical absorption change

A fiber-optic oxygen sensor has been developed for use in medical applications. The sensor´s viologen indicator becomes strongly absorbant after brief UV stimulation, and then returns to the transparent state. The rate of indicator return to transparency is proportional to the local oxygen concentration. Indicator absorbance is monitored with a red LED and receiving photodiode, and absorbance data are processed by a dedicated CPU. The solid-state sensor system has performance comparable to existing oxygen measurement techniques, and may be applicable for both in vitro and in vivo oxygen measurements.