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The association of the [Ln(hfac)3(H2O)2] metallic building blocks with the new ligand [1,1’-binaphthalene]-8,8’-diylbis(diphenylphosphine oxide) (L) led to the formation of three mononuclear complexes of formula [Ln(hfac)3(L)] (LnIII = Eu (1), Dy (2) and Yb (3)). The mononuclear character of the compounds is due to the bidentate coordination mode adopted by L to link the metal. L allows the observation of the characteristic visible 5D0  7FJ (J = 0-4) EuIII- and near infrared 2F5/2  2F7/2 YbIII- emissions while 2 is only weakly emissive due to the mismatch between the energy positions of the triplet excited state of the ligand and DyIII emissive state. The magnetic data reveal a field-induced Single-Molecule Magnet (SMM) behavior for 2 and 3 with an efficient suppression of the Quantum Tunneling of the Magnetization (QTM). The slow magnetic relaxation occurs through a Raman process while the Orbach contribution is discarded as confirmed by the correlation with the MJ states energy splitting provided by the luminescence spectrum of 3, Depto. de Química Inorgánica, Fac. de Ciencias Químicas, TRUE, pub

Depto. de Química Inorgánica, Fac. de Ciencias Químicas, TRUE, pub

Photodynamic therapy (PDT) ideally relies on the administration, selective accumulation and photoactivation of a photosensitizer (PS) into diseased tissues. In this context, we report a new heavy-atom-free fluorescent G-quadruplex (G4) DNA-binding PS, named DBI. We reveal by fluorescence microscopy that DBI preferentially localizes in intraluminal vesicles (ILVs), precursors of exosomes, which are key components of cancer cell proliferation. Moreover, purified exosomal DNA was recognized by a G4-specific antibody, thus highlighting the presence of such G4-forming sequences in the vesicles. Despite the absence of fluorescence signal from DBI in nuclei, light-irradiated DBI-treated cells generated reactive oxygen species (ROS), triggering a 3-fold increase of nuclear G4 foci, slowing fork progression and elevated levels of both DNA base damage, 8-oxoguanine, and double-stranded DNA breaks. Consequently, DBI was found to exert significant phototoxic effects (at nanomolar scale) toward cancer cell lines and tumor organoids. Furthermore, in vivo testing reveals that photoactivation of DBI induces not only G4 formation and DNA damage but also apoptosis in zebrafish, specifically in the area where DBI had accumulated. Collectively, this approach shows significant promise for image-guided PDT.

Synthetic procedures, experimental details of physical measurements, IR spectra and MS diagrams of all complexes, details, tables and figures of SCXRD molecular structures, and detailed emission spectra and analysis

The ligand H3 L (6-[3-oxo-3-(2-hydroxyphenyl)propionyl]pyridine-2-carboxylic acid), which exhibits two different coordination pockets, has been exploited to engender and study energy transfer (ET) in two dinuclear [LnIII LnIII '] analogues of interest, [EuYb] and [NdYb]. Their structural and physical properties have been compared with newly synthesised analogues featuring no possible ET ([EuLu], [NdLu], and [GdYb]) and with the corresponding homometallic [EuEu] and [NdNd] analogues, which have been previously reported. Photophysical data suggest that ET between EuIII and YbIII does not occur to a significant extent, whereas emission from YbIII originates from sensitisation of the ligand. In contrast, energy migration seems to be occurring between the two NdIII centres in [NdNd], as well as in [NdYb], in which YbIII luminescence is thus, in part, sensitised by ET from Nd. This study shows the versatility of this molecular platform to further the investigation of lanthanide-to-lanthanide ET phenomena in defined molecular systems.

Aza-boron-dipyrromethenes (Aza-BODIPYs) are an increasingly studied class of fluorophores. They can be seen as an azadipyrromethene (“aza-DIPY”) ligand rigidified by a metalloid, a boron atom. Based on this idea, a series of complexes of group 13 metals (aluminum and gallium) have been synthesized and characterized. The impact of the metal and of the nature of the substituents of aza-DIPY core were investigated. The photophysical and electrochemical properties were determined, and an X-ray structure of an azaGaDIPY was obtained. These data reveal that azaGaDIPY and azaAlDIPY exhibit significant red-shifted fluorescence compared to their analogue aza-BODIPY. Their emission can go up to 800 nm for the maximum emission length and up to NIR-II for the emission tail. This, associated with their electrochemical stability (no metal release whether oxidized or reduced) makes them a promising class of fluorophores for optical medical imaging. Moreover, X-ray structure and molecular modeling studies have shown that this redshift seems to be more due to the geometry around the boron/metal than to the nature of the metal., Depto. de Química Inorgánica, Fac. de Ciencias Químicas, TRUE, pub

© 2019 The Royal Society of Chemistry. Herein we report a nanorod couple heterostructure made of dual semiconductors, in which two parallelly aligned ZnSe nanorods are connected by the growth of ZnS on both end and side facets, producing hetero-ZnS (short arms)-ZnSe (long arms)/ZnS shell nanorod couples. As evidenced by electronic structure studies, both experimental and theoretical, such core/shell nanorod couple heterostructures can act as a platform to precisely tailor the quantum confinement of charge carriers between the constituting components within a single nano-object, generating blue fluorescence after the overgrowth of an alloyed ZnCdS layer on the heterostructures. We foresee the mechanistic insights gained and electronic structures revealed in this work would shed light on the rational design of more complex heterostructures with novel functionalities.

The ligand HL (6-[3-oxo-3-(2-hydroxyphenyl)propionyl]pyridine-2-carboxylic acid), which exhibits two different coordination pockets, has been exploited to engender and study energy transfer (ET) in two dinuclear [LnLn′] analogues of interest, [EuYb] and [NdYb]. Their structural and physical properties have been compared with newly synthesised analogues featuring no possible ET ([EuLu], [NdLu], and [GdYb]) and with the corresponding homometallic [EuEu] and [NdNd] analogues, which have been previously reported. Photophysical data suggest that ET between Eu and Yb does not occur to a significant extent, whereas emission from Yb originates from sensitisation of the ligand. In contrast, energy migration seems to be occurring between the two Nd centres in [NdNd], as well as in [NdYb], in which Yb luminescence is thus, in part, sensitised by ET from Nd. This study shows the versatility of this molecular platform to further the investigation of lanthanide-to-lanthanide ET phenomena in defined molecular systems.

© 2019 The Royal Society of Chemistry. Herein we report a nanorod couple heterostructure made of dual semiconductors, in which two parallelly aligned ZnSe nanorods are connected by the growth of ZnS on both end and side facets, producing hetero-ZnS (short arms)-ZnSe (long arms)/ZnS shell nanorod couples. As evidenced by electronic structure studies, both experimental and theoretical, such core/shell nanorod couple heterostructures can act as a platform to precisely tailor the quantum confinement of charge carriers between the constituting components within a single nano-object, generating blue fluorescence after the overgrowth of an alloyed ZnCdS layer on the heterostructures. We foresee the mechanistic insights gained and electronic structures revealed in this work would shed light on the rational design of more complex heterostructures with novel functionalities.

Herein we report a nanorod couple heterostructure made of dual semiconductors, in which two parallelly aligned ZnSe nanorods are connected by the growth of ZnS on both end and side facets, producing hetero-ZnS (short arms)-ZnSe (long arms)/ZnS shell nanorod couples. As evidenced by electronic structure studies, both experimental and theoretical, such core/shell nanorod couple heterostructures can act as a platform to precisely tailor the quantum confinement of charge carriers between the constituting components within a single nano-object, generating blue fluorescence after the overgrowth of an alloyed ZnCdS layer on the heterostructures. We foresee the mechanistic insights gained and electronic structures revealed in this work would shed light on the rational design of more complex heterostructures with novel functionalities.