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AP: Agrophysik

AP 5: Konzepte und Methoden

AP 5.1: Hauptvortrag

Dienstag, 18. März 1997, 14:30–15:15, Phy

NOVEL ESR-LUMINESCENCE TECHNIQUES FOR STUDY OF MOLECULAR DYNAMICS AND REDOX STATUS OF CELLS AND TISSUES — •Gertz Likhtenstein — Ben-Gurion University of the Negev, Dept. of Chemistry, P.O.B. 653, Beer-Sheva 84105, Israel

The proposed techniques are based upon two physical phenomena: 1. Quenching of fluorescence in dual chromophore-nitroxide supermolecules (DCNS) by a nitroxide fragment which is strongly sensitive to the fragment reactions with reductants and free radicals. 2. Photoisomerization of fluorescent trans-stilbenes (ST) to fluorescence-silent cis-stilbenes dependent upon in certain condition on microviscosity and sterical hindrances of surrounding media. Introducing DCNS ans ST in cells and tissues as specific molecular probes followed by monitoring their properties by ESR and steady-state fluorescence spectroscopy allows to investigate molecular dynamics and redox status of objects of interest.