Long-lifetime green-emitting Tb

Abstract

The present report describes a new approach to stain bacteria by means of rare earth complexes. We demonstrate with selected Gram-negative and positive bacteria (Escherichia coli, Micrococcus luteus, Bacillus megaterium) that these microbes can be stained efficiently with derivatives of N-phenylanthranilic acid, flufenamic acid in particular, and Tb3+ ions. Hence, the inherent advantages of rare earth complexes, e.g. strong optical absorption (>50 000 L × M−1 × cm−1) due to the antenna effect, large Stokes’ shifts (~10 000 cm−1) and very long emission decay times (millisecond range), and, not least, enhanced photostability can be fully exploited in fluorescence microscopy and spectroscopy of the bacteria; foreseeably, these findings will also be useful in flow cytometry and ELISA techniques.

High brightness red emitting polymer beads for immunoassays: Comparison between trifluoroacetylacetonates of Europium

“…The Eu 3+ beads form the very core of the present comparison. Some useful green emitting complexes shall be mentioned ( Assunção et al, 2021 ; Kasprzycka et al, 2021 ; Rochowiak et al, 2022 ; Assunção et al, 2023 ), however, green emitting beads will be dealt with elsewhere. Next to Eu(ttfa) 3 , Eu(btfa) 3 and Eu(ntfa) 3 , we include a novel Eu(3-phenanthtryl-trifluoro diketonate), complex, Eu(ptfa) 3 , and compare the corresponding TOPO complexes’ properties as well as polystyrene beads containing them from “one hand”; the chemical structures of above complexes are reproduced in Figure 1 .…”