{"title":"Spectroscopic Insights Into DPA Upconversion in DNA/Ru(bpy)32+ Hybrid Films","authors":"Ryuki Ozawa, Takashi Tachikawa, Norihisa Kobayashi, Kazuki Nakamura","doi":"10.1002/cptc.70344","DOIUrl":"https://doi.org/10.1002/cptc.70344","url":null,"abstract":"<p>We report a mechanistic study of upconverted luminescence of 9,10-diphenylanthracene (DPA) in a DNA/Ru(bpy)<sub>3</sub><sup>2+</sup> hybrid film, focusing on the spatial characteristics of upconversion and the role of mesoscopic aggregated structures. In our previous work, this hybrid system enabled low-voltage electrochemiluminescence (ECL) with a response time of less than 100 μs through electrochemically triggered upconversion. However, the detailed mechanism, particularly the role of mesoscopic aggregated structures, has remained unclear. Here, by combining microstructural observation and spectroscopic analyses, we demonstrate that photoexcited upconverted luminescence of DPA occurs preferentially at aggregated regions of the DNA/Ru(bpy)<sub>3</sub><sup>2+</sup> hybrid film. Time-resolved measurements show concentration-dependent quenching of the Ru(bpy)<sub>3</sub><sup>2+</sup> excited state by DPA, consistent with triplet–triplet energy transfer (TTET) from Ru(bpy)<sub>3</sub><sup>2+</sup> to DPA followed by triplet–triplet annihilation upconversion (TTA-UC). Furthermore, postwashing spectroscopic measurements indicate that DPA is preferentially retained in association with the aggregated regions. These observations support an important role of the mesoscopic aggregated structures in the TTET and TTA-UC processes.</p>","PeriodicalId":10108,"journal":{"name":"ChemPhotoChem","volume":"10 11","pages":""},"PeriodicalIF":3.0,"publicationDate":"2026-11-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149356110","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
ChemPhotoChemPub Date : 2026-11-05DOI: 10.1002/cptc.70273
Franco M. Cabrerizo, Iván Maisuls, M. Paula Denofrio, M. Alejandra Mirabal-Carrizo, Peter R. Ogilby, Cristian A. Strassert, Ezequiel Wolcan, Sergio M. Bonesi, Rosa Erra-Balsells
{"title":"Unifying the Photophysical Profile of Carbazoles: A Comprehensive Study of Triplet-State Properties and Sensitized Singlet Oxygen Yields","authors":"Franco M. Cabrerizo, Iván Maisuls, M. Paula Denofrio, M. Alejandra Mirabal-Carrizo, Peter R. Ogilby, Cristian A. Strassert, Ezequiel Wolcan, Sergio M. Bonesi, Rosa Erra-Balsells","doi":"10.1002/cptc.70273","DOIUrl":"https://doi.org/10.1002/cptc.70273","url":null,"abstract":"<p>Carbazole (Cz) and its derivatives represent a class of organic chromophores with wide-ranging applications in photochemistry, photobiology, and materials science. Although the absorption and fluorescence properties of many Cz derivatives are known, a unified framework connecting this information to triplet-state properties and photosensitizing efficacy is lacking. This current report provides a comprehensive photophysical characterization of 36 Cz derivatives, systematically unifying older data with new experimental measurements to establish robust structure–property relationships. The photophysical behavior was characterized by using steady-state and time-resolved spectroscopic measurements in acetonitrile at 298 K and in a 2-methyl-THF glassy matrix at 77 K. The temperature-dependence (ranging from 4 to 300 K) of emissive properties of selected Cz derivatives in poly(methyl methacrylate) films was also measured. We also report Cz photosensitized singlet dioxygen (O<sub>2</sub>(a<sup>1</sup>Δ<sub>g</sub>)) quantum yields and rate constants for Cz-mediated O<sub>2</sub>(a<sup>1</sup>Δ<sub>g</sub>) removal/deactivation for the entire series of derivatives in acetonitrile. We complement experimental data with conceptual density functional theory calculations of relevant excited state parameters (i.e., vertical ionization potential, vertical electron affinity, electronegativity, electrophilicity, and nucleophilicity). The results presented herein facilitate a better understanding of Cz photophysics and, thereby, better set the stage for the rational development of new functional materials and compounds.</p>","PeriodicalId":10108,"journal":{"name":"ChemPhotoChem","volume":"10 11","pages":""},"PeriodicalIF":3.0,"publicationDate":"2026-11-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/cptc.70273","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149356293","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
ChemPhotoChemPub Date : 2026-11-05DOI: 10.1002/cptc.70339
Aoi Nakahara, Haruka Koshino, Tomoyuki Mochida
{"title":"Liquid-State Photoreactions of Ru-Containing Ionic Liquids With PF5CN Anions: Arene-Dependent Coordination Modes and Thermal Reversibility","authors":"Aoi Nakahara, Haruka Koshino, Tomoyuki Mochida","doi":"10.1002/cptc.70339","DOIUrl":"https://doi.org/10.1002/cptc.70339","url":null,"abstract":"<p>Functional liquids that respond to external stimuli have recently attracted considerable attention. We have previously developed Ru-containing photoreactive ionic liquids bearing multidentate coordinating anions that undergo photoinduced transformations into polynuclear complexes or coordination polymers. In this study, we synthesized two Ru-containing ionic liquids, [Ru(C<sub>5</sub>H<sub>5</sub>)(<i>N</i>-methyl-<i>N</i>-hexylaniline)]PF<sub>5</sub>CN ([<b>1</b>]PF<sub>5</sub>CN) and [Ru(C<sub>5</sub>H<sub>5</sub>)(octylbenzene)]PF<sub>5</sub>CN ([<b>2</b>]PF<sub>5</sub>CN), containing the monodentate anion PF<sub>5</sub>CN<sup>−</sup>, and investigated their photoreactivity. Upon UV irradiation, the arene ligands dissociated from Ru and recoordinated together with two PF<sub>5</sub>CN<sup>−</sup> anions to form mononuclear anionic complexes [Ru(C<sub>5</sub>H<sub>5</sub>)(PF<sub>5</sub>CN)<sub>2</sub>(L)]<sup>−</sup> (L = the corresponding arene ligand). Under the conditions examined, the photoreactions did not proceed to completion. The resulting mixed-anion ionic liquids contained the starting cation ([<b>1</b>]<sup>+</sup> or [<b>2</b>]<sup>+</sup>) and comparable amounts of uncoordinated PF<sub>5</sub>CN<sup>−</sup> and the corresponding complex anion. The arene ligand was <i>N</i>-coordinated in the complex anion formed from [<b>1</b>]PF<sub>5</sub>CN and η<sup>2</sup>-coordinated in that from [<b>2</b>]PF<sub>5</sub>CN. The photoreaction of [<b>1</b>]PF<sub>5</sub>CN was thermally reversible, regenerating the original ionic liquid and enabling reversible photo/thermal changes in ionic conductivity. By contrast, the photoreaction of [<b>2</b>]PF<sub>5</sub>CN was irreversible, with decomposition occurring upon heating.</p>","PeriodicalId":10108,"journal":{"name":"ChemPhotoChem","volume":"10 11","pages":""},"PeriodicalIF":3.0,"publicationDate":"2026-11-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149356038","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
ChemPhotoChemPub Date : 2026-11-05DOI: 10.1002/cptc.70341
Hongying Wang, Yu Zhao
{"title":"Light-Driven Nanomaterials for Precision Biomedical Applications","authors":"Hongying Wang, Yu Zhao","doi":"10.1002/cptc.70341","DOIUrl":"https://doi.org/10.1002/cptc.70341","url":null,"abstract":"<p>Light-driven nanomaterials have emerged as versatile platforms for precision medicine. Their noninvasive nature, high spatiotemporal precision, and remote controllability enable unprecedented control over biological processes. These materials transduce external light stimuli into physicochemical changes through mechanisms such as light-driven isomerization, light-driven cleavage, and light-driven heat or molecular generation. This review summarizes recent advances in light-driven nanomaterials from the perspectives of three fundamental response mechanisms and discusses how these mechanisms have been exploited to achieve precise control of drug release, disease diagnosis, enzyme activity, and cell fate. Finally, current challenges and future opportunities toward deeper tissue applications and clinical translation are discussed.</p>","PeriodicalId":10108,"journal":{"name":"ChemPhotoChem","volume":"10 11","pages":""},"PeriodicalIF":3.0,"publicationDate":"2026-11-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149356100","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Photophysical Properties and Excited-State Dynamics of Luminescent N,O-Chelated Benzimidazole-Based Boron Complexes","authors":"Sota Abe, Erina Hiramatsu, Tetsuro Katayama, Akihiro Furube, Atsushi Tabata, Yasushi Yoshida, Shoko Ueta, Shunta Nakamura, Yukihiro Arakawa, Keiji Minagawa, Fumitoshi Yagishita","doi":"10.1002/cptc.70343","DOIUrl":"https://doi.org/10.1002/cptc.70343","url":null,"abstract":"<p>Luminescent <i>N</i>,<i>O</i>-chelated boron complexes are promising fluorescent materials owing to their rigid molecular structures and favorable photophysical properties. In this study, a series of luminescent <i>N</i>,<i>O</i>-chelated benzimidazole-based boron complexes were synthesized, and their photophysical properties and excited-state dynamics were systematically investigated by steady-state and time-resolved spectroscopic studies, supported by theoretical calculations. The complexes exhibited bright blue fluorescence with photoluminescence quantum yields of up to 0.76, whereas their absorption and emission properties were only slightly affected by the electronic nature of the boron-bound aryl substituents. The calculations revealed that the lowest-energy absorption originates predominantly from the HOMO→LUMO transition, while transient absorption spectroscopy provided insight into the excited-state relaxation pathway. Representative complex <b>2a</b> exhibited low cytotoxicity and preferential mitochondrial localization, suggesting its potential as a fluorescent probe for mitochondrial imaging.</p>","PeriodicalId":10108,"journal":{"name":"ChemPhotoChem","volume":"10 11","pages":""},"PeriodicalIF":3.0,"publicationDate":"2026-11-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/cptc.70343","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149310858","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
ChemPhotoChemPub Date : 2026-10-31DOI: 10.1002/cptc.70327
Ru He, Yixin Zhang, Yiyun Chen
{"title":"Controlling Radical Reactivity for Visible-Light Bioorthogonal Chemistry","authors":"Ru He, Yixin Zhang, Yiyun Chen","doi":"10.1002/cptc.70327","DOIUrl":"https://doi.org/10.1002/cptc.70327","url":null,"abstract":"<p>Bioorthogonal chemistry enables selective reactions within complex biological environments. Visible-light photocatalysis expands this toolbox by generating carbon-centered radicals through single-electron transfer under mild conditions, enabling selective bond-forming transformations with spatiotemporal control. Unlike broader photocatalytic transformations in biology, bioorthogonal radical reactions that selectively couple exogenous partners without reacting with native biological functionalities have not been systematically examined from the perspective of radical reactivity control. The central challenge is to control radical reactivity such that productive coupling outcompetes biological quenching while maintaining chemoselectivity. This review examines two complementary strategies to address this challenge: kinetic trapping of transient alkyl radicals and thermodynamic stabilization of persistent ketyl radicals. Framing representative systems through physical-organic principles—including radical lifetime, polarity, and reaction kinetics—we highlight applications in nucleic acid and protein modifications, protein–protein cross-linking, and live-cell labeling. Finally, we discuss emerging opportunities in biocompatible photocatalysts, long-wavelength activation, and in vivo applications, providing a conceptual framework for the design of next-generation visible-light bioorthogonal chemistries.</p>","PeriodicalId":10108,"journal":{"name":"ChemPhotoChem","volume":"10 11","pages":""},"PeriodicalIF":3.0,"publicationDate":"2026-10-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149312798","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Design Strategies of Cyanine Dyes Bearing Aryl-Piperazinyl Groups for Molecular Photoacoustic Imaging","authors":"Koki Tsuchiya, Hideo Takakura, Naoya Ieda, Akari Mukaimine, Tomohiro Ishikawa, Ryo Shintate, Manami Miyashita, Masato Kobayashi, Miya Ishihara, Tetsuya Taketsugu, Mikako Ogawa","doi":"10.1002/cptc.70334","DOIUrl":"https://doi.org/10.1002/cptc.70334","url":null,"abstract":"<p>Photoacoustic (PA) imaging offers the potential for deep-tissue visualization, but the development of dyes specifically responsive to diverse lesion environments remains insufficient. To address this problem, we synthesized cyanine dyes incorporating various aryl-piperazinyl groups at the central carbon of the polymethine chain, aiming to modulate their PA signals in response to various biological processes such as enzyme activity or reactions induced by reactive oxygen species (ROS). When various aryl substituents were incorporated into the piperazinyl cyanine scaffold, each dye showed a distinct absorption spectrum depending on the electron-donating/withdrawing ability of the substituents. Density functional theory (DFT) optimization and natural population analysis (NPA) revealed that dyes with highly electron-withdrawing aryl substituents exhibit reduced electron localization in the conjugated system and reduced bond-length alternation. Conformational analysis further showed substituent-dependent preferences for different low-energy conformers, suggesting that both electronic structure and molecular conformation contribute to the observed absorption spectral changes. PA spectra of these dyes also changed depending on the aryl substituents, suggesting that the mechanism of these aryl-piperazinyl cyanine dyes could serve as a design principle for environment-responsive PA dyes in the future.</p>","PeriodicalId":10108,"journal":{"name":"ChemPhotoChem","volume":"10 11","pages":""},"PeriodicalIF":3.0,"publicationDate":"2026-10-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149312695","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
ChemPhotoChemPub Date : 2026-10-31DOI: 10.1002/cptc.70337
Kanupriya Khandelwal, Fang-Chung Chen, Ganesh D. Sharma
{"title":"Recent Advances in the Self-Assembled Interlayers for Organic Solar Cells: Materials and Device Engineering","authors":"Kanupriya Khandelwal, Fang-Chung Chen, Ganesh D. Sharma","doi":"10.1002/cptc.70337","DOIUrl":"https://doi.org/10.1002/cptc.70337","url":null,"abstract":"<p>Organic solar cells (OSCs) have made remarkable progress over the past decade, driven by advancements in device architecture, interfacial engineering, and nonfullerene small-molecule acceptors (NF–SMAs). The power conversion efficiency of OSCs has reached up to 21% due to the strong intramolecular charge-transfer characteristics of NFSMAs and the work function aligning properties of self-assembled monolayers (SAMs). Despite these achievements, OSCs still lag in terms of stability and scalability for commercialization. This review highlights the recent progress in SAM-engineered OSCs, emphasizing their molecular designs, fabrication strategies, and multifunctional roles in work function modification, charge generation, transport, and extraction. Novel SAM design and functionalization approaches have also been addressed. Stability challenges, efficiency–durability tradeoffs, and scalability considerations are also discussed, offering insights into the future prospects of SAM-integrated OSC technology. Further improvement through interfacial and morphology engineering is crucial for the large-scale commercialization of OSCs.</p>","PeriodicalId":10108,"journal":{"name":"ChemPhotoChem","volume":"10 11","pages":""},"PeriodicalIF":3.0,"publicationDate":"2026-10-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149312797","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
ChemPhotoChemPub Date : 2026-10-30DOI: 10.1002/cptc.70333
Pavel V. Kolesnichenko, Sebastian Inacker, Nils Oberhof, Kilian Rösel, Andreas Dreuw, Norbert A. Hampp, Tiago Buckup
{"title":"On the Molecular Origin of Photoinduced Dimerization of 3- and 4-Phenylcoumarin","authors":"Pavel V. Kolesnichenko, Sebastian Inacker, Nils Oberhof, Kilian Rösel, Andreas Dreuw, Norbert A. Hampp, Tiago Buckup","doi":"10.1002/cptc.70333","DOIUrl":"https://doi.org/10.1002/cptc.70333","url":null,"abstract":"<p>Due to their ability to undergo photocycloaddition and cycloreversion reactions under continuous irradiation, coumarins are well-established building blocks for advanced photo-responsive materials. However, fundamental structure–function relationships for the targeted design of coumarin-based functional materials remain largely unexplored. Here, using transient absorption spectroscopy and quantum chemical calculations, we aim to bridge this gap by investigating 3- and 4-phenyl-7-methoxycoumarin. Despite their structurally similar nature, a pronounced difference in their photoinduced behavior is observed: 3-phenyl-7-methoxycoumarin follows a triplet formation pathway mediated by the phenyl moiety, while 4-phenyl-7-methoxycoumarin returns to the electronic ground state on an ultrafast timescale via an S<sub>1</sub>/S<sub>0</sub> near-degeneracy along the lactone C─O bond stretch within the coumarin frame, consistent with a conical intersection. Therefore, only 3-phenyl-7-methoxycoumarin dimerizes in the long-lived triplet state under continuous irradiation, making it a suitable building block for photoreactive functional materials, as alternative fast non-radiative decay channels are suppressed.</p>","PeriodicalId":10108,"journal":{"name":"ChemPhotoChem","volume":"10 11","pages":""},"PeriodicalIF":3.0,"publicationDate":"2026-10-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/cptc.70333","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149312658","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Compact Near-Infrared-Absorbing Triarylmethane Dyes Based on Antiaromatic Fluorenyl Cations","authors":"Hayato Kitaoka, Natsuki Tamano, Kazuki Kobayashi, Masato Morita, Motohiro Yasui, Tsutomu Konno, Shigeyuki Yamada","doi":"10.1002/cptc.70332","DOIUrl":"https://doi.org/10.1002/cptc.70332","url":null,"abstract":"<p>Electronic-structure control using antiaromaticity offers an effective molecular design strategy for developing compact organic near-infrared (NIR)-absorbing dyes. However, current NIR-absorbing dyes are costly, toxic, or difficult to synthesize. In this study, we designed and synthesized donor–π–acceptor-type triarylmethane dyes combining an antiaromatic fluorenyl cation framework with an electron-donating julolidine unit. DFT, TD–DFT, NICS, and structural analyses indicated the formation of the fluorenyl cation framework enhances antiaromatic character and planarity and narrows the HOMO–LUMO gap, while electron-donating substituents at the 3,6-positions further promote long-wavelength absorption. The NMe<sub>2</sub>-substituted dye <b>1b-ClO</b><sub><b>4</b></sub> exhibited an absorption maximum at 696 nm in CH<sub>2</sub>Cl<sub>2</sub>, with an absorption edge extending beyond 900 nm. Counteranion exchange had little effect on the absorption wavelength, whereas repeated measurements revealed appreciable variability in absorption intensity. In addition, <b>1b-ClO</b><sub><b>4</b></sub> showed weak photoluminescence (PL) at 916 nm upon excitation at 706 nm, with a PL quantum yield below 0.01. Photostability under the LED irradiation conditions employed in this study showed some dependence on the counteranion. The dye also showed little spectral change under acidic conditions but pronounced absorption changes upon base addition. These results demonstrate that control of the fluorenyl cation framework and donor strength provides a promising strategy for compact NIR-absorbing dyes.</p>","PeriodicalId":10108,"journal":{"name":"ChemPhotoChem","volume":"10 11","pages":""},"PeriodicalIF":3.0,"publicationDate":"2026-10-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/cptc.70332","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149312717","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}