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Thermally activated delayed fluorescence (TADF) assisted fluorescence organic light‐emitting devices (TAF‐OLEDs), also known as hyperfluorescence OLEDs, sometimes have limited operational lifetimes, making them unsuitable for industrial applications. Although, this limitation is believed to originate from the irreversible degradation of constituent materials, the chemical processes underlying this degradation remain elusive. This study enables to better understand the chemical origins of the degradation processes by identifying key degradation intermediates in emission layers comprising 2,8‐di‐tert‐butyl‐5,11‐bis(4‐tert‐butylphenyl)‐6,12‐diphenyltetracene (TBRb) as the fluorescent emitter and 1,4‐azaborin‐based molecules exhibiting multi‐resonance (MR) TADF behaviors, 5,9‐diphenyl‐5,9‐diaza‐13b‐boranaphtho[3,2,1‐de]anthracene (DABNA‐1) and 9‐([1,1′‐biphenyl]‐3‐yl)‐N,N,5,11‐tetraphenyl‐5,9‐dihydro‐5,9‐diaza‐13b‐boranaphtho[3,2,1‐de]anthracen‐3‐amine (DABNA‐2), as exciton sensitizers. Despite the sensitizers facilitating energy transfer to TBRb, they also reduce the device's longevity. While the singlet and triplet excitons of TBRb, as well as excitons of the sensitizers, prove to be relatively stable, the radical ions of the sensitizers prove to be the key limit to device longevity. Comparisons with donor–acceptor‐type TADF exciton sensitizers, 2,4,5,6‐tetrakis(9H‐carbazol‐9‐yl)benzene‐1,3‐dicarbonitrile (4CzIPN), 10,10′‐(sulfonyldi‐4,1‐phenylene)bis[9,10‐dihydro‐9,9‐dimethylacridine] (DMAC‐DPS), and 10‐[4‐(4,6‐diphenyl‐1,3,5‐triazin‐2‐yl)phenyl]‐9,10‐dihydro‐9,9‐dimethylacridine (DMAC‐TRZ), corroborate the findings, pointing to radical ions as primary degradation intermediates. This knowledge is essential for enhancing the durability of TAF‐OLEDs in future designs. [ABSTRACT FROM AUTHOR]

A multi‐resonance (MR) fluorophore exhibiting circularly polarized luminescence (CPL) holds a significant promise for enhancing the utility of organic light‐emitting devices. To meet this demand, we have devised molecular dyads having azaoxaborin MR emitters based on homochiral (R)‐ and (S)‐1,1′‐bi‐2‐naphthol. The synthesized 12,12′‐di‐tert‐butyl‐9,9′‐bi(8,8′‐dioxa‐4b,4′b‐diaza‐14b,14′b‐diborafluorantheno[1,2,3‐de]tetracene) products (TBNBOCz) exhibit strong blue fluorescence, with a remarkable 100% fluorescence quantum yield and an extremely narrow full width at half‐maximum of 22 nm. However, unexpectedly, TBNBOCz exhibits negligible electric circular dichroism and CPL activities. Chiroptical investigations into the reaction precursors reveals an occurrence of racemization in the borylation step. This result emphasizes the importance of understanding synthetic processes and their impact on the chiroptical properties. [ABSTRACT FROM AUTHOR]

This research elucidates the effects of structural modulations on electroluminescent Au(I) complexes, shedding light on factors governing radiative and nonradiative processes. A series of Au(I) complexes, fortified with ortho‐substituents in carbene and amido ligands, are subjected to rigorous structural, photophysical, and quantum chemical investigations, which unveil distinct structural and electronic effects exerted by the ligands. The investigations reveal that nonradiative processes are governed primarily by the energy‐gap law. Radiative processes are observed to have a weak correlation with the mutual interactions of the molecular orbitals of carbene and amido ligands. Rather, it is discovered that an accumulation of the negative charge in the Au 5d orbital in the excited state decelerates radiative processes. The effectiveness of these findings is substantiated through the larger external quantum efficiency of electroluminescence devices employing the Au(I) complex, in comparison to those based on the archetypical Au(I) complex and the organic thermally activated delayed fluorescent molecule. These compelling revelations underscore the untapped potential of Au(I) complexes in the advancement of electroluminescence technology and advocate for continued investigations into the intriguing domain of ligand structural control. [ABSTRACT FROM AUTHOR]

Two‐coordinate coinage metal complexes have emerged as promising emitters for highly efficient organic light‐emitting devices (OLEDs). However, achieving efficient long‐wavelength electroluminescence emission from these complexes remains as a daunting challenge. To address this challenge, molecular design strategies aimed at bolstering the photoluminescence quantum yield (Φ) of Au(I) complex emitters in low‐energy emission regions are investigated. By varying amido ligands, a series of two‐coordinate Au(I) complexes is developed that exhibit photoluminescence peak wavelengths over a broad range of 533−750 nm. These complexes, in particular, maintain Φ values up to 10% even in the near‐infrared emission region, overcoming the constraints imposed by an energy gap. Quantum chemical calculations and photophysical analyses reveal the action of radiative control, which serves to overcome the energy gap law, becomes more pronounced as the overlap between hole and electron distributions (Sr(r)) in the excited state increases. It is further elucidated that Sr(r) increases with the distance between the hole‐distribution centroid and the nitrogen atom in an amido ligand. Finally, multilayer OLEDs involving the Au(I) complex emitters exhibit performances beyond the borderline of the electroluminescence wavelength−external quantum efficiency space set by previous devices of coinage metal complexes. [ABSTRACT FROM AUTHOR]

In this study, we introduced the electron‐donating group (−OH) to the aromatic rings of Ru(salophen)(NO)Cl (0) (salophenH2=N,N′‐(1,2‐phenylene)bis(salicylideneimine)) to investigate the influence of the substitution on NO photolysis and NO‐releasing dynamics. Three derivative complexes, Ru((o‐OH)2‐salophen)(NO)Cl (1), Ru((m‐OH)2‐salophen)(NO)Cl (2), and Ru((p‐OH)2‐salophen)(NO)Cl (3) were developed and their NO photolysis was monitored by using UV/Vis, EPR, NMR, and IR spectroscopies under white room light. Spectroscopic results indicated that the complexes were diamagnetic Ru(II)−NO+ species which were converted to low‐spin Ru(III) species (d5, S=1/2) and released NO radicals by photons. The conversion was also confirmed by determining the single‐crystal structure of the photoproduct of 1. The photochemical quantum yields (ΦNOs) of the photolysis were determined to be 0>1, 2, 3 at both the visible and UV excitations. Femtosecond (fs) time‐resolved mid‐IR spectroscopy was employed for studying NO‐releasing dynamics. The geminate rebinding (GR) rates of the photoreleased NO to the photolyzed complexes were estimated to be 0≃1, 2, 3. DFT and TDDFT computations found that the introduction of the hydroxyl groups elevated the ligand π‐bonding orbitals (π (salophen)), resulting in decrease of the HOMO‐LUMO gaps in 1–3. The theoretical calculations suggested that the Ru‐NNO bond dissociations of the complexes were mostly initiated by the ligand‐to‐ligand charge transfer (LLCT) of π(salophen)→π*(Ru−NO) with both the visible and UV excitations and the decreasing ΦNOs could be explained by the changes of the electronic structures in which the photoactivable bands of 1–3 have relatively less contribution of transitions related with Ru‐NO bond than those of 0. [ABSTRACT FROM AUTHOR]

In the dynamic domain of chiroptical technologies, it is imperative to engineer emitters endowed with circularly polarized luminescence (CPL) properties. This research demonstrates an advancement by employing a combined top‐down and bottom‐up strategy for the simultaneous amplification of photoluminescence quantum yield (Φ) and the luminescence dissymmetry factor (glum). Square‐planar Pt(II) complexes form helical assemblies, driven by torsional strain induced by bis(nonyl) chains. Integration of chiral anions leads these assemblies to prefer distinct helical sense. This arrangement activates the metal‐metal‐to‐ligand charge transfer (MMLCT) transition that is CPL‐active, with Φ and |glum| observing an upswing contingent on the charge number and aryl substituents in chiral anions. Utilizing the soft‐lithographic micromolding in capillaries technique, we could fabricate exquisitely‐ordered, one‐dimensional co‐assemblies to achieve the metrics to Φ of 0.32 and |glum| of 0.13. Finally, our spectroscopic research elucidates the underlying mechanism for the dual amplification, making a significant stride in the advancement of CPL‐active emitters. [ABSTRACT FROM AUTHOR]

Glutathione (GSH) is an essential molecule that plays a pivotal role in maintaining intracellular redox homeostasis, as well as other physiological processes. However, the chemical mechanisms underlying the GSH-induced processes remain insufficiently understood due to the lack of appropriate detection tools. Fluorescence GSH imaging can serve as a useful principle for the rapid, convenient, and non-destructive detection of GSH in living organisms. In this study, we developed a fluorescent GSH probe based on a linear, homoleptic Au(I) complex with two 1,3-diphenylbenzimidazolium carbene ligands. The Au(I) complex produced a fluorescence turn-on response to GSH. Fluorescence GSH signaling was characterized with a short response time of a few seconds. The rapid response was attributed to the displacement of the carbene ligand with GSH, which involved a labile inner-sphere coordination interaction. Finally, we demonstrated the biological utility of our GSH probe by unambiguously discriminating between different GSH levels in normal and senescent preadipocytes. [ABSTRACT FROM AUTHOR]

Recently, LG Display completed the "EX Technology" development and is prioritizing technological innovation. This technology includes deuterium technology and personalization algorithms, which increase screen brightness (luminance) by 30% compared to existing OLEDs while producing more accurate and natural colors. In this paper, we will describe how deuterium technology can improve the lifetime of OLED products and the degradation mechanism of deuterated materials. By replacing the C‐H bond with a C‐D bond, isotope species exhibit electrochemical stability, leading to a longer device lifetime. [ABSTRACT FROM AUTHOR]

In this paper, we propose an ultrahigh‐resolution organic light‐emitting diodes (OLEDs) pixels patterned by conventional photolithography through by incorporating silicone into phosphorescent small‐molecule networks. This silicone‐integrated phosphorescent organic light‐emitting diode (SI‐phOLED), in which silicone molecules are homogeneously crosslinked with small‐molecule light‐emitting materials, can effortlessly achieve to 3,000 PPI ultrahigh‐resolution patterns using the photolithography process. [ABSTRACT FROM AUTHOR]

Achieving large external quantum efficiencies, narrow bandwidths, and a long operational lifetime at high brightness remains the largest hurdle to developing organic blue‐emitting devices. Here, a material strategy is demonstrated that can meet these conditions. The strategy is based on linear heteroleptic Au(I) complex exciton harvesters and multiresonance thermally activated delayed fluorescence (MR‐TADF) emitters. The organic electroluminescence devices produce blue emission with Commission Internationale de l'Eclairage chromaticity coordinates of (0.108, 0.160), a narrow full‐width at half‐maximum value of 20 nm, and a maximum external quantum efficiency (EQE) as high as 30.2%. Notably, the EQE value remains 22.2% at 2000 cd m−2, whereas conventional control devices with an organic exciton harvester suffer from huge roll‐offs in quantum efficiency. An additional benefit of the device is a one‐order‐of‐magnitude improvement in its operational lifetime compared with that of the control device. Finally, the investigations reveal that the improvements are attributable to the unique ability of the Au(I) complexes for ultrafast triplet exciton harvest. In addition, the Au(I) complexes can facilitate Förster energy transfer to the MR‐TADF emitter, with effective suppression of hazardous triplet–triplet Dexter energy transfer. It is believed that the research is helpful in commercializing high‐efficiency and stable blue electroluminescence devices. [ABSTRACT FROM AUTHOR]

Cyclometalated Ir(III) complexes exhibit strong phosphorescence emission with lifetime of submicroseconds to several microseconds at room temperature. Their synthetic versatility enables broad control of physical properties, such as charge and lipophilicity, as well as emission colors. These favorable properties have motivated the use of Ir(III) complexes in luminescent bioimaging applications. This review examines the recent progress in the development of phosphorescent biolabels and sensors based on Ir(III) complexes. It begins with a brief introduction about the basic principles of the syntheses and photophysical processes of cyclometalated Ir(III) complexes. Focus is placed on illustrating the broad imaging utility of Ir(III) complexes. Phosphorescent labels illuminating intracellular organelles, including mitochondria, lysosomes, and cell membranes, are summarized. Ir(III) complexes capable of visualization of tumor spheroids and parasites are also introduced. Facile chemical modification of the cyclometalating ligands endows the Ir(III) complexes with strong sensing ability. Sensors of temperature, pH, CO2, metal ions, anions, biosulfur species, reactive oxygen species, peptides, and viscosity have recently been added to the molecular imaging tools. This diverse utility demonstrates the potential of phosphorescent Ir(III) complexes toward bioimaging applications. [ABSTRACT FROM AUTHOR]

Circularly polarized luminescence (CPL) with tunable chirality is currently a challenging issue in the development of supramolecular nanomaterials. We herein report the formation of helical nanoribbons which grow into helical tubes through dynamic helicity inversion. For this, chiral PtII complexes of terpyridine derivatives, namely S‐trans‐1 and R‐trans‐1, with respective S‐ and R‐alanine subunits and incorporating trans‐double bonds in the alkyl chain were prepared. In DMSO/H2O (5 : 1 v/v), S‐trans‐1 initially forms a fibrous self‐assembled product, which then undergoes dynamic transformation into helical tubes (left‐handed or M‐type) through helical ribbons (right‐handed or P‐type). Interestingly, both helical supramolecular architectures are capable of emitting CPL signals. The metastable helical ribbons show CPL signals (glum=±4.7×10−2) at 570 nm. Meanwhile, the nanotubes, which are the thermodynamic products, show intense CPL signals (glum=±5.6×10−2) at 610 nm accompanied by helicity inversion. This study provides an efficient way to develop highly dissymmetric CPL nanomaterials by regulating the morphology of metallosupramolecular architectures. [ABSTRACT FROM AUTHOR]

A distinctive sustainable approach has been developed to afford highly functionalized CF3–hydroquinone derivatives as potent biologically active molecules. The synthetic protocol involves the photoirradiation of a mixture of easily accessible benzoquinones and CF3SO2Na. This process generates a quinhydrone charge-transfer complex of benzoquinone and its in situ generated hydroquinone in the presence of a small amount of hydrogen donors, more preferably water. The subsequent formation of a transient ternary complex involving CF3SO2Na elicits photoinduced charge-transfer (CT), thereby producing CF3–hydroquinones. The present method is highly practical and atom-economical whilst avoiding the use of any sacrificial electron donors. Furthermore, the unique ternary complex intermediate permits site-selective three-component trifluoromethylation in the presence of vinyl arenes. [ABSTRACT FROM AUTHOR]

NO photorelease and its dynamics for two {RuNO}6 complexes, Ru(salophen)(NO)Cl (1) and Ru(naphophen)(NO)Cl (2), with salen-type ligands bearing π-extended systems (salophenH2 = N,N′-(1,2-phenylene)-bis(salicylideneimine) and naphophenH2 = N,N′-1,2-phenylene-bis(2-hydroxy-1-naphthylmethyleneimine)) were investigated. NO photolysis was performed under white room light and monitored by UV/Vis, EPR, and NMR spectroscopies. NO photolysis was also performed under 459 and 489 nm irradiation for 1 and 2, respectively. The photochemical quantum yields of the NO photolysis (ΦNO) of both 1 and 2 were determined to be 9% at the irradiation wavelengths. The structural and spectroscopic characteristics of the complexes before and after the photolysis confirmed the conversion of diamagnetic Ru(II)(L)(Cl)–NO+ to paramagnetic S = ½ Ru(III)(L)(Cl)–solvent by photons (L = salophen2− and naphophen2−). The photoreleased NO radicals were detected by spin-trapping EPR. DFT and TDDFT calculations found that the photoactive bands are configured as mostly the ligand-to-ligand charge transfer (LLCT) of π(L) → π*(Ru–NO), suggesting that the NO photorelease was initiated by the LLCT. Dynamics of NO photorelease from the complexes in DMSO under 320 nm excitation were investigated by femtosecond (fs) time-resolved mid-IR spectroscopy. The primary photorelease of NO occurred for less than 0.32 ps after the excitation. The rate constants (k−1) of the geminate rebinding of NO to the photolyzed 1 and 2 were determined to be (15 ps)−1 and (13 ps)−1, respectively. The photochemical quantum yields of NO photolysis (ΦNO, λ = 320 nm) were estimated to be no higher than 14% for 1 and 11% for 2, based on the analysis of the fs time-resolved IR data. The results of fs time-resolved IR spectroscopy and theoretical calculations provided some insight into the overall kinetic reaction pathway, localized electron pathway or resonance pathway, of the NO photolysis of 1 and 2. Overall, our study found that the investigated {RuNO}6 complexes, 1 and 2, with planar N2O2 ligands bearing π-extended rings effectively released NO under visible light. [ABSTRACT FROM AUTHOR]

Integration of distinct materials to form heterostructures enables the proposal of new functional devices based on emergent physical phenomena beyond the properties of the constituent materials. The optical responses and electrical transport characteristics of heterostructures depend on the charge and exciton transfer (CT and ET) at the interfaces, determined by the interfacial energy level alignment. In this work, heterostructures consisting of aggregates of fluorescent molecules (DY1) and 2D semiconductor MoS2 monolayers are fabricated. Photoluminescence spectra of DY1/MoS2 show quenching of the DY1 emission and enhancement of the MoS2 emission, indicating a strong electronic interaction between these two materials. Nanoscopic mappings of the light‐induced contact potential difference changes rule out the CT process at the interface. Using femtosecond transient absorption spectroscopy, the rapid interfacial ET process from DY1 aggregates to MoS2 and a fourfold extension of the exciton lifetime in MoS2 are elucidated. These results suggest that the integration of 2D inorganic semiconductors with fluorescent molecules can provide versatile approaches to engineer the physical characteristics of materials for both fundamental studies and novel optoelectronic device applications. [ABSTRACT FROM AUTHOR]

Organic photoredox catalysts with a long excited-state lifetime have emerged as promising alternatives to transition-metal-complex photocatalysts. This paper explains the effectiveness of using long-lifetime photoredox catalysts for organic transformations, focusing on the structures and photophysics that enable long excited-state lifetimes. The electrochemical potentials of the reported organic, long-lifetime photocatalysts are compiled and compared with those of the representative Ir(III)- and Ru(II)-based catalysts. This paper closes by providing recent demonstrations of the synthetic utility of the organic catalysts. 1 Introduction 2 Molecular Structure and Photophysics 3 Photoredox Catalysis Performance 4 Catalysis Mediated by Long-Lifetime Organic Photocatalysts 4.1 Photoredox Catalytic Generation of a Radical Species and its Addition to Alkenes 4.2 Photoredox Catalytic Generation of a Radical Species and its Addition to Arenes 4.3 Photoredox Catalytic Generation of a Radical Species and its Addition to Imines 4.4 Photoredox Catalytic Generation of a Radical Species and its Addition to Substrates Having C≡X Bonds (X=C, N) 4.5 Photoredox Catalytic Generation of a Radical Species and its Bond Formation with Transition Metals 4.6 Miscellaneous Reactions of Radical Species Generated by Photoredox Catalysis 5 Conclusions [ABSTRACT FROM AUTHOR]

Lewis acid–base interactions of 1-hydroxy-10-phenylacridone produce large chromic shifts in fluorescence, due to a change in a multi-resonance intramolecular charge-transfer (ICT) character to a dipolar ICT character. [ABSTRACT FROM AUTHOR]

A new type of photoactivable NO‐releasing ruthenium nitrosyl complex, [Ru(EPBP)Cl(NO)], with a tetradentate ligand, N,N'‐(ethane‐1,2‐diyldi‐o‐phenylene)‐bis(pyridine‐2‐carboxamide) (= H2EPBP) was synthesized. Single crystal X‐ray crystallography revealed that the complex has a distorted octahedral coordination geometry and NO is positioned at cis to Cl− ion. NO‐photolysis was observed under a white room light. The photodissociation of Ru−NO bond was identified by various techniques including X‐ray crystallography, IR, UV/Vis absorption, electron paramagnetic resonance (EPR), and NMR spectroscopies. Quantum yields for the NO‐photolysis of the complex in CH3OH, CHCl3, DMSO, CH3CN, and CH3NO2 were measured to be 0.19–0.36 with 400 (±5) nm excitation. Density functional theory (DFT) and time‐dependent density functional theory (TDDFT) calculations were performed to understand the details of the photodissociation of the complex. The calculations suggest that the NO photolysis is most likely initiated by the electronic transition from the aniline moiety π MOs (π (aniline)) of the EPBP2− chelating ligand to the π‐antibonding MO of Ru−NO (π*(Ru−NO)). Experimental and theoretical investigations indicate that the EPBP2− ligand provides an effective platform forming ruthenium nitrosyl complexes useful for NO‐photoreleasing. [ABSTRACT FROM AUTHOR]

A system capable of photoreleasing tyramine has been developed. The photodonor system consists of an isoindole cage of tyramine and a biscyclometalated Ir(III) complex singlet oxygen (1O2) photosensitizer. Photoirradiation at a wavelength of 365 nm produces tyramine, as evidenced by mass spectrometry and 1H NMR spectroscopy. The photorelease proceeds through two steps involving the formation of a Diels–Alder‐type [2 + 4] cycloadduct of 1O2, followed by the slow and spontaneous decomposition of the adduct into tyramine and 2‐benzoylbenzophenon. [ABSTRACT FROM AUTHOR]

Molecules displaying dual emission (DE) disobey Kasha's rule. Although such molecules are valuable in various applications, the limited availability of DE materials has retarded full utilization of their photofunction. We discovered DE behaviors from a novel series of molecular dyads composed of coumarin and cyclic donors. Our DE dyads are unique in that they display short-wavelength prompt fluorescence and long-wavelength delayed fluorescence. Electrochemical, spectroscopic, quantum chemical, and structural investigations were conducted to elucidate the mechanism underlying the DE behaviors. Our mechanistic studies reveal that DE originates from the high-lying singlet π–π* and the low-lying singlet intramolecular charge-transfer (1ICT) transition states. The two states are under kinetic control between (1) internal conversion and (2) El Sayed-rule-allowed intersystem crossing, followed by reverse intersystem crossing. The latter process enables population of the 1ICT state through detouring via triplet manifolds. In addition, our investigation indicates that DE is also governed by conformeric heterogeneity of the cyclic amino donor between pseudo-axial and pseudo-equatorial forms. These findings are important because they point to an intimate coupling between the photophysical processes of DE and thermally activated delayed fluorescence. Finally, photonic utility of the DE behaviors has been demonstrated by luminescence ratiometric monitoring of the temperature and a triplet quencher. [ABSTRACT FROM AUTHOR]

The short operation lifetime of organic light‐emitting devices originates from irreversible degradation of organic materials, but the mechanism by which degradation initiates has been insufficiently understood. We discovered that degradation is triggered by electron‐transfer interactions between a dopant and a host exciton. A numerical model predicting operational stability has been developed. [ABSTRACT FROM AUTHOR]

Irreversible chemical reactions are responsible for limited operational lifetime of organic light‐emitting devices (OLEDs). These reactions are triggered by highly reactive polaron pairs present in the emissive layer of OLEDs. Fast recombination of the polaron pairs is, therefore, crucial for slow degradation and high stability of OLED materials. Here, a study of the formation and annihilation of close polaron pairs in binary mixtures of wide bandgap hosts and a series of blue‐phosphorescent Ir(III) complex dopants, including two novel compounds, is reported. OLED devices containing doped light‐emitting layer are fabricated, and their operational lifetimes are estimated. Although inaccessible in solid films, charge recombination kinetics inside the polaron pairs is measured in liquid solutions using nanosecond laser flash photolysis. Multiscale computer simulations are applied to connect experimental results in different media and predict recombination rates in the device, with proper account taken of the inner‐ and outersphere reorganization in nonpolar materials. Predicted rates correlate with measured operational lifetimes, which demonstrates the key role of polaron pairs in the OLED degradation process. The developed methodology is useful for the rational design of novel OLED materials with higher efficiency and stability. [ABSTRACT FROM AUTHOR]

Cells use gaseous molecules such as nitric oxide (NO) to transmit both intracellular and intercellular signals. In principle, the endogenous small molecules regulate physiological changes, but it is unclear how randomly diffusive molecules trigger and discriminate signaling programs. Herein, it is shown that gasotransmitters use time‐dependent dynamics to discriminate the endogenous and exogenous inputs. For a real‐time stimulation of cell signaling, we synthesized a photo‐cleavable metal–nitrosyl complex, [CoIII(MDAP)(NO)(CH3CN)]2+ (MDAP=N,N′‐dimethyl‐2,11‐diaza[3,3](2,6)pyridinophane), which can stably deliver and selectively release NO with fine temporal resolution in the cytosol, and used this to study the extracellular signal‐regulated kinases (ERKs), revealing how cells use both exogenous and endogenous NO to disentangle cellular responses. This technique can be to understand how diverse cellular signaling networks are dynamically interconnected and also to control drug delivery systems. [ABSTRACT FROM AUTHOR]

Molecular imaging employing cyclometalated Ir(III) complexes is one of the fastest growing research areas. In this minireview, the key advances in phosphorescent bioimaging and photodynamic applications employing cyclometalated Ir(III) complexes are introduced. Focus is on understanding the structure−property relationships, with the aim to provide useful guidance to future development of molecular materials showing the intended photofunctions. The research covered in this minireview demonstrates that cyclometalated Ir(III) complexes can serve as versatile platforms for biological applications. [ABSTRACT FROM AUTHOR]