Selective recognition of bacterial membranes by zinc(ii)-coordination complexes

Abstract

Two fluorophore-dipicolylamine-Zn2+ conjugates are shown by epifluorescence microscopy to stain the membranes of bacterial cells in preference to mammalian cells.

Squaraine Rotaxanes: Superior Substitutes for Cy‐5 in Molecular Probes for Near‐Infrared Fluorescence Cell Imaging

“…Angewandte Chemie animal cells. [24] To compare the targeting ability and photostability of a squaraine rotaxane directly with a related Cy-5 probe, we prepared three fluorophore Zn-DPA conjugates; squaraine rotaxane 3 with two Zn-DPA targeting ligands, squaraine rotaxane 4 with one Zn-DPA targeting ligand, and Cy-5 probe 5 with one Zn-DPA targeting ligand. As expected, all three probes strongly associate with the periphery of bacterial cells, which allowed photobleaching experiments to be conducted.…”

Dye Encapsulation

“…For example, attachment of zinc coordinated dipicolylamine groups, which are known to target bacterial cell surfaces, produces a bright, photostable, and non -toxic probe for bacteria imaging. 38 This probe is over 20 times more photostable than an analogous probe composed of the popular cyanine dye, Cy5. The enhanced photostability allows acquisition of fl uorescent movies of bacterial cell division; these movies were previously unavailable due to photobleaching of the fl uorescent probe.…”

Zinc(II)-Dipicolylamine Coordination Complexes as Targeting and Chemotherapeutic Agents for Leishmania major

“…Fluorescent ZnDPA probes are effective imaging agents for dead and dying mammalian cells (which expose anionic phosphatidylserine) in a range of cell culture systems and small animal models of disease (19)(20)(21)(22)(23)(24)(25)(26). ZnDPA probes also target the anionic surfaces of bacteria, and they have been used for imaging infection in animal models (27)(28)(29)(30)(31)(32)(33). Some ZnDPA complexes are known to have antibiotic activity due to their capacity to disrupt bacterial membranes (31).…”