title: A Highly Selective Potassium Sensor for the Detection of Potassium in Living Tissues.
abstract: The development of highly selective sensors for potassium is of great interest in biology. Two new hydrosoluble potassium sensors (Calix-COU-Alkyne and Calix-COU-Am) based on a calix[4]arene bis(crown-6) and an extended coumarin were synthesized and characterized. The photophysical properties and complexation studies of these compounds have been investigated and show high molar extinction coefficients and high fluorescence quantum yields. Upon complexation with potassium in the millimolar concentration range, an increase of one- and two-photon fluorescence emission is detected. A twofold fluorescence enhancement is observed upon excitation at λ=405 nm. The ligands present excellent selectivity for potassium in the presence of various competitive cations in water and in a physiological medium. The photophysical properties are not affected by the presence of a large amount of competing cations (Na+, Ca2+, Mg2+, etc.). Ex vivo measurements on mouse hippocampal slices show that Calix-COU-Alkyne accumulates extracellularly and does not alter the neuronal activity. Furthermore, the sensor can be utilized to monitor slow extracellular K+increase induced by inhibition of K+entry into the cells.
authors: PPSM, ENS Cachan, CNRS, Université Paris Saclay, 61 avenue du Président Wilson, 94235, Cachan Cedex, France.
authors: Alexis
authors: A
authors: Depauw
authors: Center for Interdisciplinary Research in Biology, Collège de France, Centre National de la, Recherche Scientifique UMR 7241, Institut National de la Santé et de la Recherche Médicale U1050, Labex Memolife, PSL Research University, Paris, France.
authors: Elena
authors: E
authors: Dossi
authors: PPSM, ENS Cachan, CNRS, Université Paris Saclay, 61 avenue du Président Wilson, 94235, Cachan Cedex, France.
authors: Naresh
authors: N
authors: Kumar
authors: SPEC, CEA, CNRS, Université Paris-Saclay, 91191 Gif-sur-Yvette Cedex (France.
authors: Céline
authors: C
authors: Fiorini-Debuisschert
authors: Neurophysiology Department, Sorbonne University, UPMC University Paris 06, Centre Hospitalo-Universitaire Pitié-Salpêtrière, APHP, 75013, Paris, France.|INSERM U1129 "Infantile Epilepsies and Brain Plasticity", Paris Descartes University, PRES Sorbonne Paris Cité, CEA, Gif sur Yvette, France.
authors: Gilles
authors: G
authors: Huberfeld
authors: PPSM, ENS Cachan, CNRS, Université Paris Saclay, 61 avenue du Président Wilson, 94235, Cachan Cedex, France.|Institut des Sciences Moléculaire d'Orsay (ISMO), CNRS, Université Paris-Sud, Université Paris Saclay, 91405, Orsay, France.
authors: Minh-Huong
authors: MH
authors: Ha-Thi
authors: Center for Interdisciplinary Research in Biology, Collège de France, Centre National de la, Recherche Scientifique UMR 7241, Institut National de la Santé et de la Recherche Médicale U1050, Labex Memolife, PSL Research University, Paris, France.
authors: Nathalie
authors: N
authors: Rouach
authors: PPSM, ENS Cachan, CNRS, Université Paris Saclay, 61 avenue du Président Wilson, 94235, Cachan Cedex, France. isabelle.leray@ens-cachan.fr.
authors: Isabelle
authors: I
authors: Leray
mesh_terms: D000818:Animals; D047250:Calixarenes / Q000737:chemistry*; D002412:Cations / Q000737:chemistry*; D005453:Fluorescence; D008024:Ligands; D051379:Mice; D015394:Molecular Structure; D017785:Photons; D011188:Potassium / Q000737:chemistry*
chemical_list: D002412:Cations; D008024:Ligands; D047250:Calixarenes; D011188:Potassium
keywords: calixarenes; fluorescence; potassium; sensors; two-photon absorption