[Effect of oxygen on the fluorescence of sol-gel with ruthenium complexes].

Different Ru complexes were used in an organically modified sol-gel (ormosil) sensing film to character their quenching behaviors to oxygen. The sensing film with tris-(4,7-diphenyl-1, 10-phenanthroline) ruthenium(II) [Ru(dpp)(2+)3] as an indicator was selected because of its characteristics with high quenching efficiency, fast response time, high luminescence intensity and long-term stability. The quenching behavior of the sensing film greatly depended on the content of dimethyldimethoxysilane (DiMe-DMOS) in ormosil because DiMe-DMOS changed the polarity of sensing film. A home-made fluorescence quenching system was set up for oxygen determination based on a blue LED (lambda max = 460 nm ) as an exciting light source. Th e response time was 30 s from saturatednitrogen to oxygen in water, and 90 s from saturated oxygen to nitrogen.