In this paper we report the use of phase sensitive fluorometry to obtain preliminary results from opto-chemical fluorescent oxygen nanosensors. PEBBLE (Probe Encapsulated By Biologically Localized Embedding) sensors were fabricated by immobilizing tris(4,7-diphenyl—1, 10-phenanthroline)Ru(II) chloride and tris(1,10-phenanthroline)Ru(II) chloride within a polyacrylamide matrix. PEBBLEs have diameters of 20-200 nm and exhibit excellent performance for dissolved oxygen detection. Their performance is compared with micrometer-sized (10-20 μm) optical fiber sensors and free dye in solution. Oxygen sensing ability of PEBBLEs was tested in the presence of other quenchers and compared with free dyes in solution. While PEBBLEs have been developed for minimally invasive intracellular chemical analysis, they show additional advantages, such as increased dynamic range, compared to microsensors, and an absence of interference (quenching) by heavy ions, in contrast to free dye solutions.


Originally published in SPIE Conference on Advances in Fluorescence Technology IV, San Jose, CA, Jan. 1999, SPIE Vol. 3602, Proc. SPIE 3602, 156 (1999). DOI:10.1117/12.347517


nanosensor, microsensor, optode, oxygen sensor, phase modulation

Subject Categories

Fluorimetry, Optical detectors, Oxygen--Physiological transport


Bioimaging and biomedical optics | Nanoscience and Nanotechnology



Publication Date


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Copyright 1999 One print or electronic copy may be made for personal use only. Systematic reproduction and distribution, duplication of any material in this paper for a fee or for commercial purposes, or modification of the content of the paper are prohibited.

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Society of Photo-Optical Instrumentation Engineers

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