Assessing Wound Healing in Vivo Using a Dual-Function Phosphorescent Probe Sensitive to Tissue Oxygenation and Regenerating Collagen.

Levels of tissue oxygenation and collagen regeneration are critical indicators in the early evaluation of wound healing. Traditionally, these factors have been assessed using separate instruments and different methodologies. Here, we adopt the spatially averaged phosphorescence lifetime approach using Re-diimine complexes (Re-probe) to enable simultaneous quantification of these two critical factors in healing wounds.

Biocompatible Re-Containing Block Copolymers for Intracellular pH Mapping in the PLIM Mode.

Monitoring of intracellular pH is of great importance since deviation of this parameter from the "normal" magnitudes can be considered as an indicator of various pathologies. Thus, the development of new efficient and biocompatible sensors suitable for application in biological systems and capable of quantitative pH estimation remains an urgent chemical task. Herein, we report the synthesis of a series of phosphorescent rhenium [Re(NN)(CO)(PR)] complexes based on the NN diimine ligands containing pH-responsive carboxylic groups and styrene-containing phosphine ligands.

DPPM-Bridged Binuclear Pt(II) Pincer Complexes: Chemistry, Structure, and Photophysics in Solution Revisited.

A series of luminescent binuclear ([dppm{Pt(NNC)}]) and mononuclear ([PPhPt(NNC)]) complexes containing pincer ligands were synthesized and characterized. Photophysical characteristics of both types of complexes were studied in dichloromethane solution. In the solid phase, the binuclear compounds adopt a syn configuration where the {Pt(NNC)} fragments are held together due to intramolecular Pt-Pt bonding and π-stacking of the pincer ligand aromatic systems.

Unusual Effects of the Metal Center Coordination Mode on the Photophysical Behavior of the Rhenium(I) and Rhenium(I)-Iridium(III) Complexes.

Binuclear transition-metal complexes based on conjugated systems containing coordinating functions are potentially suitable for a wide range of applications, including light-emitting materials, sensors, light-harvesting systems, photocatalysts, etc., due to energy-transfer processes between chromophore centers. Herein we report on the synthesis, characterization, photophysical, and theoretical studies of relatively rare rhenium(I) and rhenium(I)-iridium(III) dyads prepared by using the nonsymmetrical polytopic ligands ( and ) with the strongly conjugated phenanthroline and imidazole-quinoline/pyridine coordinating fragments.

Cyclometalated platinum(II) complexes with acyclic diaminocarbene ligands for OLED application.

A novel series of cyclometalated platinum(II) complexes bearing acyclic diaminocarbene (ADC) ancillary ligands were designed and prepared. Their photophysical properties were systematically studied through experimental and theoretical investigations. All complexes exhibit green phosphorescence with a quantum efficiency of up to 45% in 2 wt% doped PMMA film at room temperature.

Rhenium(I) Block Copolymers Based on Polyvinylpyrrolidone: A Successful Strategy to Water-Solubility and Biocompatibility.

A series of diphosphine Re(I) complexes - have been designed via decoration of the archetypal core {Re(CO)(N^N)} through the installations of the phosphines and bearing the terminal double bond, where N^N = 2,2'-bipyridine (), 4,4'-di-tert-butyl-2,2'-bipyridine () or 2,9-dimethyl-1,10-phenanthroline () and = diphenylvinylphosphine, and = 4-(diphenylphosphino)styrene. These complexes were copolymerized with the corresponding N-vinylpyrrolidone-based Macro-RAFT agents of different polymer chain lengths to give water-soluble copolymers of low-molecular ) and high-molecular block-copolymers containing rhenium complexes. Compounds -, as well as the copolymers and , demonstrate phosphorescence from a MLCT excited state typical for this type of chromophores.

Hybrid Inorganic-Organic Complexes of Zn, Cd, and Pb with a Cationic Phenanthro-diimine Ligand.

The phosphonium-decorated phenanthro-imidazolyl pyridine ligand, Br, readily reacts with zinc(II) and cadmium(II) bromides to give inorganic-organic zero-dimensional compounds [ZnBr][ZnBr] () and [()CdBr][CdBr] (), respectively, upon crystallization. These salts are moderately fluorescent in the solid state under ambient conditions (λ = 458 nm, Φ = 0.11 for ; λ = 460 nm, Φ = 0.

Functionalizing Collagen with Vessel-Penetrating Two-Photon Phosphorescence Probes: A New In Vivo Strategy to Map Oxygen Concentration in Tumor Microenvironment and Tissue Ischemia.

The encapsulation and/or surface modification can stabilize and protect the phosphorescence bio-probes but impede their intravenous delivery across biological barriers. Here, a new class of biocompatible rhenium (Re ) diimine carbonyl complexes is developed, which can efficaciously permeate normal vessel walls and then functionalize the extravascular collagen matrixes as in situ oxygen sensor. Without protective agents, Re -diimine complex already exhibits excellent emission yield (34%, λ   = 583 nm) and large two-photon absorption cross-sections (σ   = 300 GM @ 800 nm) in water (pH 7.

Modulation of Metallophilic and π-π Interactions in Platinum Cyclometalated Luminophores with Halogen Bonding.

Luminescent cyclometalated complexes [M(C^N^N)CN] (M=Pt, Pd; HC^N^N=pyridinyl- (M=Pt 1, Pd 5), benzyltriazolyl- (M=Pt 2), indazolyl- (M=Pt 3, Pd 6), pyrazolyl-phenylpyridine (M=Pt 4)) decorated with cyanide ligand, have been explored as nucleophilic building blocks for the construction of halogen-bonded (XB) adducts using IC F as an XB donor. The negative electrostatic potential of the CN group afforded CN⋅⋅⋅I noncovalent interactions for platinum complexes 1-3; the energies of XB contacts are comparable to those of metallophilic bonding according to QTAIM analysis. Embedding the chromophore units into XB adducts 1-3⋅⋅⋅IC F has little effect on the charge distribution, but strongly affects Pt⋅⋅⋅Pt bonding and π-stacking, which lead to excited states of MMLCT (metal-metal-to-ligand charge transfer) origin.

Supramolecular Construction of Cyanide-Bridged Re Diimine Multichromophores.

The reactions of labile [Re(diimine)(CO)(HO)] precursors (diimine = 2,2'-bipyridine, bpy; 1,10-phenanthroline, phen) with dicyanoargentate anion produce the dirhenium cyanide-bridged compounds [{Re(diimine)(CO)}CN)] (1 and 2). Substitution of the axial carbonyl ligands in 2 for triphenylphosphine gives the derivative [{Re(phen)(CO)(PPh)}CN] (3), while the employment of a neutral metalloligand [Au(PPh)(CN)] affords heterobimetallic complex [{Re(phen)(CO)}NCAu(PPh)] (4). Furthermore, the utilization of [Au(CN)], [Pt(CN)], and [Fe(CN)] cyanometallates leads to the higher nuclearity aggregates [{Re(diimine)(CO)NC} M] (M = Au, x = 2, 5 and 6; Pt, x = 4, 7 and 8; Fe, x = 6, 9 and 10).

Chromophore-Functionalized Phenanthro-diimine Ligands and Their Re(I) Complexes.

A series of diimine ligands has been designed on the basis of 2-pyridyl-1 H-phenanthro[9,10- d]imidazole (L1, L2). Coupling the basic motif of L1 with anthracene-containing fragments affords the bichromophore compounds L3-L5, of which L4 and L5 adopt a donor-acceptor architecture. The latter allows intramolecular charge transfer with intense absorption bands in the visible spectrum (lowest λ 464 nm (ε = 1.

Linking Re and Pt Chromophores with Aminopyridines: A Simple Route to Achieve a Complicated Photophysical Behavior.

The bifunctional aminopyridine ligands H N-(CH ) -4-C H N (n=0, L1; 1, L2; 2, L3) have been utilized for the preparation of the rhenium complexes [Re(phen)(CO) (L1-L3)] (1-3; phen=phenanthroline). Complexes 2 and 3 with NH -coordinated L2 and L3, respectively, were coupled with cycloplatinated motifs {Pt(ppy)Cl} and {Pt(dpyb)} (ppy=2-phenylpyridine, dpyb=dipyridylbenzene) to give the bimetallic species [Re(phen)(CO) (μ-L2/L3)Pt(ppy)Cl] (4, 6) and [Re(phen)(CO) (μ-L2/L3)Pt(dpyb)] (5, 7). In solution, complexes 4 and 6 show MLCT {Re}-based emission at 298 K, which changes to the IL(ppy) state at 77 K.