209665-37-2Relevant academic research and scientific papers
Coumarin phosphorescence observed with NN Pt(ii) bisacetylide complex and its applications for luminescent oxygen sensing and triplet-triplet- annihilation based upconversion
Sun, Haiyang,Guo, Huimin,Wu, Wenting,Liu, Xin,Zhao, Jianzhang
, p. 7834 - 7841 (2011)
A dbbpy platinum(ii) bis(coumarin acetylide) complex (Pt-1, dbbpy = 4,4′-di-tert-butyl-2,2′-bipyridine) was prepared. Pt-1 shows intense absorption in the visible region (λabs = 412 nm, ε = 3.23 × 104 M-1 cm-1) compared to the model complex dbbpy Pt(ii) bis(phenylacetylide) (Pt-2, λabs = 424 nm, ε = 8.8 × 103 M-1 cm-1). Room temperature phosphorescence was observed for Pt-1 (3IL, τP = 2.52 μs, λem = 624 nm, ΦP = 2.6%) and the emissive triplet excited state was assigned as mainly intraligand triplet excited state (3IL), proved by 77 K steady state emission, nanosecond time-resolved transient absorption spectroscopy and DFT calculations. Complex Pt-1 was used for phosphorescent oxygen sensing and the sensitivity (Stern-Volmer quenching constant K SV = 0.012 Torr-1) is 12-fold of the model complex Pt-2 (KSV = 0.001 Torr-1). Pt-1 was also used as triplet sensitizer for triplet-triplet-annihilation based upconversion, upconversion quantum yield ΦUC up to 14.1% was observed, vs. 8.9% for the model complex Pt-2.
Fluorescent enzyme substrates and method for determining enzyme activities
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, (2008/06/13)
The enzyme substrate according to this invention has within its molecule both a group to be cleaved by an enzyme reaction and a group that forms a strongly fluorescent coumarin derivative through intramolecular lactonization when cleaved by the enzyme rea
