Dissolved optical oxygen sensor: Tris(2,2'-bipyridine) ruthenium (II) entrapped in siliceous zeolite-Y

ANYL 322

Toni A. Ruda, truda@chemistry.ohio-state.edu and Prabir K. Dutta, dutta@chemistry.ohio-state.edu. Department of Chemistry, The Ohio State University, 120 West 18th Avenue, Columbus, OH 43210
Optical oxygen sensors offer many advantages over electrochemical sensors for monitoring dissolved oxygen. However, a problem often encountered with optical oxygen sensors is the probe leaching from the support matrix, which causes a drift in signal and may lead to toxicity during biological monitoring. Therefore, tris(2,2'-bipyridyl) ruthenium(II) was entrapped inside the supercages of siliceous zeolite-Y via a “ship-in-a-bottle” synthetic method to act as an optical oxygen sensor. Entrapment of the probe in the siliceous zeolite-Y supercage prevents leaching of the probe, and the matrix hydrophobicity provides rapid oxygen diffusion. Dissolved oxygen sensing was monitored via luminescence intensity experiments with both gas saturated solutions and a glucose oxidase assay that allows for small changes in oxygen concentration to be made. The sensor was immobilized on the end of a fiber optic in order to monitor dissolved oxygen concentrations. Finally, the sensor was tested in macrophage cells to determine if small changes in oxygen concentration during the oxidative burst could be monitored.