Luminescent two-photon(2P)absorbing lanthanide(III)complexes hold great promise for microsocpy imaging of biological samples.Conjugating such a complex to well-chosen cell penetrating peptides(CPP)allows its controlle...Luminescent two-photon(2P)absorbing lanthanide(III)complexes hold great promise for microsocpy imaging of biological samples.Conjugating such a complex to well-chosen cell penetrating peptides(CPP)allows its controlled delivery to the cytosol of live cells.However,alkoxy-phenyl-ethynyl-picolinate,one of the best antennae for 2P sensitization of Eu^(3+),undergoes side reactions at its ethynyl group during peptide synthesis or in biological media and thus cannot be used to create such a conjugate.In this article,we evaluate the effect of substituting the ethynyl group by a phenyl one.We describe the synthesis of conjugates of the TAT CPP with Eu^(3+)complexes featuring amido-phenyl-phenyl-picolinamide,alkoxy-phenyl-phenyl-picolinamide and amido-phenyl-phenyl-picolinate ter-aryl antennae and compare their spectroscopic properties to those of analogues with bi-aryl antennae,including the amido-phenyl-picolinamide already used for 2P live cell imaging.The absorption spectrum of the teraryl antennae is red-shifted and better covers the active spectral range for 2P excitation by a Ti-sapphire laser.Among compounds with ter-aryl antennae,those with an amido electron donating group are the most interesting,showing brightness ca.4 times higher than their bi-aryl counterparts,and similar to the ethynyl-containing antenna.2P microscopy imaging of live cells incubated with the TAT-Eu^(3+)conjugate and dFFLIPTAT,a non-luminescent CPP that promotes cytosolic delivery,showed diffuse cytosolic staining of the Eu^(3+)probe.The ter-aryl-based probes showed superior performances compared to bi-aryl,with ca.80%of the cells showing Eu^(3+)staining of the cytosol.展开更多
基金Agence Nationale de la Recherche(ANR-18-CE06-0022 and ANR-21-CE29-0018)the Labex ARCANE,CBH-EUR-GS(ANR-17-EURE-0003)+1 种基金the CEA FOCUS Biomarqueurs program for financial supportthe IBISA-ISdV platform,member of the national infrastructure France-BioImaging supported by the French National Research Agency(ANR-10-INBS-04).
文摘Luminescent two-photon(2P)absorbing lanthanide(III)complexes hold great promise for microsocpy imaging of biological samples.Conjugating such a complex to well-chosen cell penetrating peptides(CPP)allows its controlled delivery to the cytosol of live cells.However,alkoxy-phenyl-ethynyl-picolinate,one of the best antennae for 2P sensitization of Eu^(3+),undergoes side reactions at its ethynyl group during peptide synthesis or in biological media and thus cannot be used to create such a conjugate.In this article,we evaluate the effect of substituting the ethynyl group by a phenyl one.We describe the synthesis of conjugates of the TAT CPP with Eu^(3+)complexes featuring amido-phenyl-phenyl-picolinamide,alkoxy-phenyl-phenyl-picolinamide and amido-phenyl-phenyl-picolinate ter-aryl antennae and compare their spectroscopic properties to those of analogues with bi-aryl antennae,including the amido-phenyl-picolinamide already used for 2P live cell imaging.The absorption spectrum of the teraryl antennae is red-shifted and better covers the active spectral range for 2P excitation by a Ti-sapphire laser.Among compounds with ter-aryl antennae,those with an amido electron donating group are the most interesting,showing brightness ca.4 times higher than their bi-aryl counterparts,and similar to the ethynyl-containing antenna.2P microscopy imaging of live cells incubated with the TAT-Eu^(3+)conjugate and dFFLIPTAT,a non-luminescent CPP that promotes cytosolic delivery,showed diffuse cytosolic staining of the Eu^(3+)probe.The ter-aryl-based probes showed superior performances compared to bi-aryl,with ca.80%of the cells showing Eu^(3+)staining of the cytosol.
