Tailoring tripodal ligands for zinc sensing

Zinc plays an important role in biological processes. It is implicated in many diseases, including those affecting the brain. Imaging zinc is becoming crucial to the elucidation of zinc concentration, distribution, kinetics and functions in cells and tissues. This review highlights recent advances in the development of picolylamine-based tripodal compounds as zinc sensors, especially our work in the field of sensing “invisible” Zn(II) using steady-state fluorescence, fluorescence lifetimes and chiroptical spectroscopy. Our approach has emphasized creative ligand design and detection schemes. Utilizing tris(2-pyridylmethyl)amine-based N₄ tripodal ligands has provided a flexible system for engineering zinc sensors with improved sensitivity, selectivity and contrast. Also included are results with tripodal ligands that have focused more on applications.