A Highly Selective Bicyclic Fluoroionophore for the Detection of Lithium Ions†

Tracking Lithium Ions via Widefield Fluorescence Microscopy for Battery Diagnostics

Direct tracking of lithium ions with time and spatial resolution can provide an important diagnostic tool for understanding mechanisms in lithium ion batteries. A fluorescent indicator of lithium ions, 2-(2-hydroxyphenyl)naphthoxazole, was synthesized and used for real-time tracking of lithium ions via widefield fluorescence microscopy. The fluorophore can be excited with visible light and was shown to enable quantitative determination of the lithium ion diffusion constant in a microfluidic model system for a plasticized polymer electrolyte lithium battery. The use of widefield fluorescence microscopy for in situ tracking of lithium ions in batteries is discussed.

Selective recognition of lithium(i) ions using Biginelli based fluorescent organic nanoparticles in an aqueous medium

Detection of lithium ions using fluorescent organic nanoparticles.

Optical probes for the detection of protons, and alkali and alkaline earth metal cations

Luminescent sensors and switches continue to play a key role in shaping our understanding of key biochemical processes, assist in the diagnosis of disease and contribute to the design of new drugs and therapies. Similarly, their contribution to the environment cannot be understated as they offer a portable means to undertake field testing for hazardous chemicals and pollutants such as heavy metals. From a physiological perspective, the Group I and II metal ions are among the most important in the periodic table with blood plasma levels of H(+), Na(+) and Ca(2+) being indicators of several possible disease states. In this review, we examine the progress that has been made in the development of luminescent probes for Group I and Group II ions as well as protons. The potential applications of these probes and the mechanism involved in controlling their luminescent response upon analyte binding will also be discussed.

Li⁺ selective podand-type fluoroionophore based on a diphenyl sulfoxide derivative bearing two pyrene groups

New podand-type fluoroionophores having two pyrene moieties: 2,2´-bis(1-pyrenylacetyloxy)diphenyl sulfide (3), 2,2´-bis(1-pyrenylacetyloxy)diphenyl sulfoxide (4), and 2,2´-bis(1-pyrenylacetyloxy)diphenyl sulfone (5), have been synthesized by connecting two 1-pyrenecarbonylmethyl groups with the two hydroxy groups of 2,2´-dihydroxydiphenyl sulfide, sulfoxide, and sulfone, respectively. Their complexation behavior toward alkali metal ions was examined by fluorescence spectroscopy. Among these fluoroionophores, compound 4, having a sulfinyl group, showed high selectivity toward Li⁺.

21-(4-Methyl-phenyl-sulfon-yl)-4,7,13,16-tetra-oxa-1,10,21-triaza-bicyclo-[8.8.5]tricosane-19,23-dione: an N-tosyl-ated macrobicyclic dilactam

The macrobicyclic title compound, C₂₃H₃₅N₃O₈S, contains two tertiary amide bridgehead N atoms and a toluene­sulfonamide N atom in the center of the five-atom bridging strand. The mol­ecule has a central cavity that is defined by the 18-membered ring identified by the N₂O₄ donor atom set and two 15-membered rings with N₃O₂ donor atom sets. The toluene­sulfonamide N atom adopts an exo orientation with respect to the central cavity, and the tosyl group is oriented on one side of the aza-bridging strand that connects the bridgehead N atoms.

Surface-Based Lithium Ion Sensor: An Electrode Derivatized with a Self-Assembled Monolayer

Self-assembled monolayers (SAMs) of 21-(16-mercaptohexadecan-1-oyl)-4,7,13,16-tetraoxa-1,10,21-triazabicyclo[8.8.5]tricosane-19,23-dione were prepared on gold. Characterization of the SAMs was carried out by sessile drop contact angle, ellipsometry, grazing angle FT-IR spectroscopy, and electrochemical techniques. The cation recognition properties of the SAM were studied by cyclic voltammetry and impedance spectroscopy. The films show moderate selectivity for detection of Li+ ions in solution over K+ and Na+, with selectivity values calculated to be log K(Li+,Na+) approximately -1.30 and log K(Li+,K+) approximately -0.92. To the best of our knowledge, this is the first demonstration of a lithium sensor fabricated using self-assembled monolayer technology.