Beyond zinc coordination: Bioimaging applications of Zn(II)-complexes

This article focuses on the bioimaging applications of fluorescent Zn(II)-complexes. Thanks to the biocompatible nature of zinc ions that makes possible the use of Zn(II)-complexes in various cell imaging applications with minimal cytotoxicity. The ability of Zn(II)-complexes to bind phosphate derived anions is important. This provides a useful way to design fluorescent probes targeting intracellular phosphates and anionic phospholipids at the cell surface, which is the characteristic feature of apoptosis. The phosphate-binding ability of Zn(II)-complexes is further used in protein labeling, targeted drug delivery, and imaging of bacterial infections. Staining of different subcellular locations is also achieved by employing fluorescent Zn(II)-complexes. Altogether, fluorescent Zn(II)-complexes represent a unique class of synthetic fluorescent probes that have several biological applications ranging from bioimaging to therapeutics. (C) 2020 Elsevier B.V. All rights reserved.