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This paper summarizes the development of a self-referenced, multi-channel, integrated optic chemical sensor technology for in-line monitoring of water quality in NASA's water revitalization subsystem, in the controlled ecological life support system for prolonged space missions. The technique uses commonly available materials and straightforward processing to produce channel waveguides in a porous glass, each channel treated with a fluorescence or absorbance based indicator that responds optically to metal ions in water. The porosity of the glass allows metal ions present in water to diffuse into the glass and interact with immobilized indicators, producing a measurable optical change.

This paper describes a novel integrated optic spacesuit atmospheric quality sensor to enhance astronaut safety by monitoring the spacesuit's closed environment. The integrated optic sensor (IOS) is made of self-calibrating miniaturized channel waveguide elements that monitor oxygen concentration in real time. Fabrication employs direct photolithographic writing of channel waveguides onto a photoactive porous glass matrix. The active channel waveguide is doped with an oxygen-sensitive fluorescent indicator. A compact phase fluorometer measures relative fluorescence lifetime -- a direct function of the oxygen partial pressure. In testing, the IOS chip demonstrated a response time of 5 seconds from 0% to 100% oxygen at STP.