Article
Chemistry, Applied
Carlos E. A. de Melo, Celso R. Nicoleti, Misael Ferreira, Miria C. dos Santos, Adrian Kreuz, Felipe S. S. Schneider, Robson da S. Oliboni, Giovanni F. Caramori, Vanderlei G. Machado
Summary: The investigation explored the use of tert-butyl groups in the electron-donor phenolate groups to tune the interactions between the probe and the solvent. The presence of tert-butyl groups increased the lipophilicity of the dyes and hindered hydrogen bonding with hydrogen bond donating solvents. Molecular dynamics simulations demonstrated the hindering effect of tert-butyl groups on hydrogen bonding with methanol and water solvent molecules.
Article
Chemistry, Physical
Andrii Kulinich, Alexander A. Ishchenko, Stanislav L. Bondarev, Valery N. Knyukshto
Summary: The UV-vis absorption and fluorescence spectra of a series of merocyanines with different heterocyclic donor and carbonyl-comprising acceptor groups were studied at 77K in frozen ethanol. The electronic structure of the molecules became more dipolar in the frozen solvent matrix compared to the liquid solvent, leading to spectral effects depending on the donor-acceptor abilities of the terminal groups. The fluorescence bands shifted hypsochromically at cryotemperature and were closely mirror-like to the absorption bands, indicating inhibited solvent rearrangement in the frozen matrix.
JOURNAL OF PHOTOCHEMISTRY AND PHOTOBIOLOGY A-CHEMISTRY
(2021)
Article
Chemistry, Organic
Kanyashree Jana, Debarghya Sarkar, Preeti Jaiswal, Jarugu Narasimha Moorthy
Summary: A set of donor-acceptor azahelical coumarins (DA-AHCs) with high fluorosolvatochromic shifts and high quantum yields in solution and solid states were designed and synthesized. The excited-state properties of these compounds were investigated, revealing the contribution of intramolecular charge transfer and crystal packing to their emission behaviors. The analysis showed that strengthened hydrogen bonding promoted quenching, efficient crystal packing promoted high emission, and loose crystal packing contributed to excited-state deactivation.
JOURNAL OF ORGANIC CHEMISTRY
(2023)
Article
Chemistry, Physical
Zimu Wei, Sushil Sharma, Abbey M. Philip, Sanchita Sengupta, Ferdinand C. Grozema
Summary: Donor-bridge-acceptor systems based on BODIPY show potential for bio-imaging and sensing applications, with their photophysical behavior depending on solvent polarity. Factors such as donor-acceptor distance and restricted rotational motion play key roles in tuning the excited state photophysics.
PHYSICAL CHEMISTRY CHEMICAL PHYSICS
(2021)
Article
Chemistry, Multidisciplinary
A. Altas, D. D. Gultekin, M. Acar, E. Cucu, A. Karatay, A. Elmali, A. Atalay, C. A. Demircan, U. Bozkaya, C. Kazaz, E. Sahin, O. . A. Bozdemir
Summary: The positions of electron-releasing and withdrawing groups on perylene monoimides (PMIs) have a significant influence on their photophysical properties. The current modification methods for PMI have limitations, making it important to synthesize PMIs through alternative approaches.
MATERIALS TODAY CHEMISTRY
(2022)
Article
Chemistry, Physical
Shalu Gupta, Marilyn Daisy Milton
Summary: Seven novel donor-acceptor-donor type push-pull quadrupolar quinoxaline scaffolds with blue or green emission in solution were successfully synthesised via Heck coupling reaction, showing tunable photophysical properties. The compounds exhibited large Stokes shifts and bathochromic shifts in emission wavelength, along with a twisted structural conformation and donor-acceptor interactions revealed by XRD studies. Reversible fluorescence switching and color modulation upon treatment with TFA and TEA were observed, with potential applications in detecting volatile acids.
JOURNAL OF PHOTOCHEMISTRY AND PHOTOBIOLOGY A-CHEMISTRY
(2022)
Article
Chemistry, Applied
Vishwa Deepak Singh, Ashish Kumar Kushwaha, Roop Shikha Singh
Summary: Three novel chalcone-based asymmetrical D-A-D'-A' chromophores have been designed and synthesized to achieve dual state emission, exhibiting varying degrees of emission in solution, aggregated, and solid states. The incorporation of different rigid and flexible moieties in the design imparts substantial solvatochromism to the compounds, with C3 showing superior dual state emission due to the inclusion of phenothiazine unit. Additionally, the compounds display remarkable acid-induced fluorescence quenching effect, particularly when exposed to trifluomacetic acid (TFA).
Article
Chemistry, Physical
Swathi Nenavath, Naresh Duvva, Ram R. R. Kaswan, Gary N. N. Lim, Francis D'Souza, Lingamallu Giribabu
Summary: Donor phenanthroimidazole (PhI) is directly connected to a BODIPY acceptor (Dyad1) through an ethynyl bridge (Dyad2). Spectroscopic and electrochemical analysis suggests minimal π-π interaction between PhI and BODIPY. The dyads exhibit quenched emission when excited at absorption maxima of PhI or BODIPY, indicating intramolecular photoinduced excitation energy transfer and electron transfer. The dyads also generate charge-separated species and have high energy transfer rate constants, making them useful for light energy harvesting applications.
JOURNAL OF PHYSICAL CHEMISTRY A
(2023)
Article
Chemistry, Multidisciplinary
Miranda M. Sroda, Friedrich Stricker, Julie A. Peterson, Alexandria Bernal, Javier Read de Alaniz
Summary: The study shows that the switching properties and concentration dependence of DASAs are influenced by solution-state dielectric and intermolecular interactions. DASAs with higher zwitterionic resonance contributions in the open form, such as first- and third-generation architectures, can have their switching kinetics controlled by ion concentration. On the other hand, DASAs with a less charge-separated open form, like second-generation architecture, are less affected by ion concentration. This highlights the importance of understanding the impact of solution properties on the design of photoswitching materials.
CHEMISTRY-A EUROPEAN JOURNAL
(2021)
Article
Chemistry, Multidisciplinary
Midori Kawashiro, Tatsuya Mori, Masato Ito, Naoki Ando, Shigehiro Yamaguchi
Summary: A new class of donor-pi-acceptor fluorophores with ortho-P(=X)R-2-substituted phenyl groups (X=O or S) as a photodissociation module is reported. The P=X moiety coordinates to the boron atom and undergoes dissociation in the excited state, resulting in dual emission from tetra- and tricoordinate boron species. The intensity ratios of the dual emission bands are sensitive to environmental parameters and single-molecule white emission can be achieved by precise tuning of the P(=X)R-2 group and the electron-donating amino moiety in solution.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2023)
Article
Spectroscopy
Si -Hong Chen, Zhao-Hua Chen, Kai Jiang, Xi-Ying Cao, Liu-Yu Chen, Jin Ouyang, Zhao-Yang Wang
Summary: We designed a series of benzoxazole-based dual-state emission luminogens and demonstrated their improved detecting performance on nitroaromatic explosives (NAEs) through multiple strategies.
SPECTROCHIMICA ACTA PART A-MOLECULAR AND BIOMOLECULAR SPECTROSCOPY
(2023)
Article
Chemistry, Applied
Dong Kyun You, Mingi Kim, Sanghee Yi, Yung Ju Seo, Wonchul Lee, Kang Mun Lee
Summary: In this study, three novel carboline-based benzothiadiazole compounds were synthesized and characterized. The compounds exhibited solvatochromic effects in different organic solvents and showed potential application prospects. The charge transfer transition mechanism of the compounds was investigated, and it was found that alpha CB had higher emissive efficiency and lower nonradiative decay compared to beta CB and gamma CB. Additionally, the crystalline powders of alpha CB displayed a high-contrast and reversible mechanochromic phenomenon.
Review
Chemistry, Multidisciplinary
Xi Chen, Xue Zhang, Xiao Xiao, Zhijia Wang, Jianzhang Zhao
Summary: Charge transfer is crucial in molecular electron donor-acceptor systems for artificial photosynthesis, photocatalysis, photovoltaics, and fundamental photochemistry. We summarized recent developments in the study of charge transfer and discussed its application in thermally activated delayed fluorescence (TADF) emitters.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2023)
Article
Chemistry, Multidisciplinary
Alexander Schulz, Frank Wuerthner
Summary: This study demonstrated a significant fluorescence enhancement for a weakly fluorescent merocyanine dye by co facially stacking it with other dyes in heterofolda-trimer architectures. This enhancement was explained by the rigidification of the emitting chromophore in the foldamer architecture and the presence of a non forbidden lowest exciton state in H-coupled heteroaggregates, suggesting a promising strategy for improved fluorophores inspired by nature's green fluorescent protein (GFP).
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2022)
Article
Chemistry, Multidisciplinary
Gana Sanil, Maciej Krzeszewski, Wojciech Chaladaj, Witold Danikiewicz, Iryna Knysh, Lukasz Dobrzycki, Olga Staszewska-Krajewska, Michal K. Cyranski, Denis Jacquemin, Daniel T. Gryko
Summary: This study presents the tandem intramolecular hydroarylation of alkynes accompanied by a 1,2-aryl shift. By utilizing the unique electron-rich character of the 1,4-dihydropyrrolo[3,2-b]pyrrole scaffold, pi-expanded, centrosymmetric pyrrolo[3,2-b]pyrroles were synthesized by reacting alkynes at the already occupied positions 2 and 5. The reaction only proceeds in the presence of cationic gold catalyst and produces unknown compounds with six conjugated rings. These synthesized compounds have potential applications in the creation of new materials with various functionalities.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2023)
Article
Chemistry, Multidisciplinary
Krzysztof Gorski, Tea Ostojic, Marzena Banasiewicz, Erik T. Ouellette, Luca Grisanti, Daniel T. Gryko
Summary: A heavy metal-free synthetic methodology for the one-step conversion of ketones into 4,5,6,7-tetrafluorobenzofurans (F(4)BFs) has been developed. It has favorable qualities such as the use of readily available substrates, broad scope, scalability, and good reaction yields. The synthesized benzofurans were previously inaccessible, and this methodology also enables the preparation of furo[2,3-b]pyrazines and difuro[2,3-c:3',2'-e]pyridazine, which have not been explored before.
CHEMISTRY-A EUROPEAN JOURNAL
(2023)
Article
Chemistry, Physical
D. Giavazzi, S. Saseendran, F. Di Maiolo, A. Painelli
Summary: This paper introduces a model that combines molecular aggregates and resonance energy transfer (RET) by utilizing electrostatic intermolecular interactions. The model can describe both RET and energy delocalization and is applicable in both weak and strong coupling regimes, while considering the quantum nature of molecular vibrations.
JOURNAL OF CHEMICAL THEORY AND COMPUTATION
(2023)
Article
Chemistry, Physical
Silvia D'Auria, Alessandro Pedrini, Ilaria Ferraboschi, Jerome Vachon, Cristina Sissa, Roberta Pinalli, Enrico Dalcanale
Summary: In this study, the researchers used two-photon microscopy (2PM) to investigate the compatibility between PE-HEMA and EVOH at the sub-micrometer level. 2PM is a nonlinear fluorescence imaging technique commonly used for thick biological tissue analysis. Polymer blending was visualized using 3D images obtained through 2PM. It was observed that the functionalized PE-HEMA, when reacted with ODIN, formed uniformly distributed blends on the surface and in the bulk, and repeated reprocessing partially reversed the compatibilization by forming ODIN dimers as the most stable H-bonding array in the solid state.
Article
Chemistry, Multidisciplinary
K. Swathi, Meleppatt Sujith, P. S. Divya, P. Merin Varghese, Andrea Delledonne, D. K. Andrea Phan Huu, Francesco Di Maiolo, Francesca Terenziani, Andrea Lapini, Anna Painelli, Cristina Sissa, K. George Thomas
Summary: The phenomenon of excited-state symmetry breaking is often observed in multipolar molecular systems, significantly affecting their photophysical and charge separation behavior. In this study, the intrinsic factors regulating excited-state symmetry breaking in multibranched systems are explored using a combination of experimental and theoretical investigation. It is found that the large Stokes shifts observed in highly symmetric phenyleneethynylenes can be explained by the presence of low-lying dark states, as confirmed by two-photon absorption measurements and TDDFT calculations. In addition, an intense fluorescence emission is observed in these systems contrary to Kasha's rule, and this behavior is explained by a novel phenomenon called symmetry swapping, which describes the inversion of the energy order of excited states as a result of symmetry breaking.
Article
Pharmacology & Pharmacy
Felipe M. Gonzalez-Fernandez, Andrea Delledonne, Sara Nicoli, Paolo Gasco, Cristina Padula, Patrizia Santi, Cristina Sissa, Silvia Pescina
Summary: This research aims to develop nanostructured lipid carriers (NLC) for periocular administration of dexamethasone acetate for the treatment of ocular inflammation. The NLC was formulated using solid and liquid lipid mixtures, resulting in a particle size of 106.9 +/- 1.2 nm, PDI = 0.104 +/- 0.019, and zeta potential = -6.51 +/- 0.575 mV. Ex vivo permeation studies showed that dexamethasone acetate was metabolized into free dexamethasone and exhibited higher permeation capabilities across both sclera and choroid tissues.
Article
Pharmacology & Pharmacy
Adriana Fantini, Luca Giulio, Andrea Delledonne, Silvia Pescina, Cristina Sissa, Sara Nicoli, Patrizia Santi, Cristina Padula
Summary: The optimization of non-invasive formulations for the delivery of high molecular weight compounds is the greatest achievement in the field of advanced drug delivery. Permeation experiments using fatty acids and bile salts as penetration enhancers showed that it is feasible to increase the mucosa permeation of high molecular weight dextrans. This study suggests that buccal administration can be used for the delivery of high molecular weight compounds.
Article
Chemistry, Inorganic & Nuclear
Silvia Ruggieri, Silvia Mizzoni, Chiara Nardon, Enrico Cavalli, Cristina Sissa, Michele Anselmi, Pier Giorgio Cozzi, Andrea Gualandi, Martina Sanadar, Andrea Melchior, Francesco Zinna, Oliver G. Willis, Lorenzo Di Bari, Fabio Piccinelli
Summary: This study synthesized and characterized three complexes and investigated their photophysical and thermodynamic properties. The results showed that the nature of the ligands had a significant impact on the properties of the complexes, and the properties of the complexes also affected their sensitization efficiency towards the metal ions. The ttaligand was found to be the optimal antenna for sensitizing Eu-(III) luminescence, while the Coum ligand sensitized better Tb-(III) luminescence.
INORGANIC CHEMISTRY
(2023)
Article
Chemistry, Physical
Francesco Bertocchi, Andrea Delledonne, Guillem Vargas-Nadal, Francesca Terenziani, Anna Painelli, Cristina Sissa
Summary: Aggregates of cyanine dyes are investigated for their tunable spectral properties in this study. The study presents a joint experimental and theoretical analysis of different types of aggregates formed by a family of cyanine dyes. The analysis rationalizes the optical spectra using an essential-state model that takes into account intermolecular interactions, molecular polarizability, and vibronic coupling.
JOURNAL OF PHYSICAL CHEMISTRY C
(2023)
Article
Chemistry, Multidisciplinary
Francesco Bertocchi, Danilo Marchetti, Sandra Doria, Mariangela di Donato, Cristina Sissa, Mauro Gemmi, Enrico Dalcanale, Roberta Pinalli, Andrea Lapini
Summary: Our study investigates the impact of hydrogen bond-assisted H-aggregate formation on the optical properties of two functionalized naphthyridine derivatives, ODIN-EtPh and ODIN-But. Through a combination of techniques including X-ray and electron crystallography, spectroscopy, and pump-probe spectroscopy, we reveal that the formation of dimers for ODIN derivatives is inhibited in polar solvents while favored in solvents with poor hydrogen bond-forming capabilities. The presence of a phenyl group linked to the ureidic unit stabilizes the charge-transfer excited state of ODIN derivatives, leading to a reduction in fluorescence emission.
CHEMISTRY-A EUROPEAN JOURNAL
(2023)
Article
Nanoscience & Nanotechnology
Andrea Delledonne, Elisa Guazzelli, Silvia Pescina, Annalisa Bianchera, Giancarlo Galli, Elisa Martinelli, Cristina Sissa
Summary: The self-assembly properties of unimer micelles were utilized to prepare fluorescent nanocarriers encapsulating hydrophobic fluorophores. These nanocarriers were composed of a copolymer containing oligoethyleneglycol and perflurohexylethyl side chains, and formed small nanoparticles (<10 nm) with tunable properties in water. An easy procedure for encapsulating a small hydrophobic molecule within the nanocarriers was presented, and experimental data showed that the fluorophore was effectively embedded and maintained its emissive properties in water. Additionally, the dye-loaded nanocarriers demonstrated efficacy as a fluorescent probe in two-photon imaging of thick ex vivo porcine scleral tissue.
ACS APPLIED NANO MATERIALS
(2023)
Article
Materials Science, Multidisciplinary
Davide Giavazzi, Marvin F. Schumacher, Luca Grisanti, Mattia Anzola, Francesco Di Maiolo, Jennifer Zablocki, Arne Luetzen, Manuela Schiek, Anna Painelli
Summary: This study provides a combined experimental and theoretical investigation of a new type of chiral aggregates with structure-correlated excitonic properties in the visible to near-infrared spectral range. It is found that different alkyl chain lengths can lead to different aggregation scenarios and spectroscopic features, including simultaneous blue- and red-shifted signatures, as well as dominant blue-shifted signatures. The calculation of circular dichroism including intermolecular charge transfer is explicitly expressed for the first time.
JOURNAL OF MATERIALS CHEMISTRY C
(2023)
Article
Materials Science, Multidisciplinary
Juraj Ovcar, Luca Grisanti, Bruno Mladineo, Aleksandra B. Djurisic, Jasminka Popovic, Ivor Loncaric
Summary: Two-dimensional lead halide perovskites hold great promise for optoelectronics, and their properties can be tuned by the number of lead halide layers and the choice of an organic spacer. Understanding the crystal structure is crucial for the rational design of materials. However, the preparation of two-dimensional lead halide perovskites in the form of films complicates the experimental determination of structure. In order to enable theoretical studies and high-throughput virtual screening, we have developed an algorithm for predicting the crystal structure of lead halide perovskites, which provides fast access to a structure suitable for further first-principles studies.
Article
Chemistry, Multidisciplinary
Andrea Delledonne, Martina Orlandini, Francesca Terenziani, Paolo Pio Mazzeo, Alessia Bacchi, Lucia Carlucci, Angiolina Comotti, Jacopo Perego, Paolo Pelagatti
Summary: Three new microporous mixed-ligand MOFs (PUM310, PUM310Me(2), and PUM310CO) were synthesized through solvothermal reactions between bis-pyridine-bis-amide ligands and 2,6-naphthalenedicarboxylic acid. The structural characterization revealed polycatenated frameworks with truncated Zn-paddle wheels, and solvent removal resulted in framework rearrangement and shrinkage. The MOFs exhibited fluorescence in the solid state, and the optical spectra indicated efficient Forster resonance energy transfer (FRET) between the ndca(2-) donor and bis-pyridine acceptors, particularly in PUM310CO.