Review
Chemistry, Analytical
Cheng Chen, Chong Fang
Summary: Amine groups are important constituents of organic dyes and have been found to influence the brightness of chromophores. This review focuses on the mechanistic insights of the twisted intramolecular charge transfer (TICT) mechanism and other less common or influential fluorescence quenching mechanisms in amine-containing fluorescent molecules. The review covers various aspects of scientific findings, including the design and synthesis of organic chromophores, theoretical calculations, and spectroscopy techniques, to understand how different amine groups affect the nonradiative decay pathways of excited states.
Article
Chemistry, Multidisciplinary
Ke Liu, Jing Zhang, Qiyuan Shi, Liping Ding, Taihong Liu, Yu Fang
Summary: This study reports a new strategy for tuning excited-state intramolecular proton transfer (ESIPT) by incorporating an excited-state intramolecular charge transfer (ESICT) process. Three o-carborane derivatives were designed to selectively detect mustard gas simulant using film-based fluorescence sensing. This work provides a reliable strategy for creating high-performance sensing fluorophores via ESIPT manipulation.
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY
(2023)
Article
Chemistry, Analytical
Cheng Chen, Sean A. Boulanger, Anatolii Sokolov, Mikhail S. Baranov, Chong Fang
Summary: Researchers discovered a novel fluorophore by incorporating a -NMe2 group into a conformationally locked GFP scaffold, showing marked solvent-polarity-dependent behavior. They revealed the formation of a TICT state through fs-TA spectroscopy and quantum calculations, which effectively quenches fluorescence. The polarity dependence of the FS -> TICT reaction barrier was mainly modulated by H-bonding capability instead of solvent viscosity.
Article
Chemistry, Multidisciplinary
Hua Li, Honglei Li, Xingzhi Wang, Yufeng Nie, Cheng Liu, Yu Dai, Jinyang Ling, Mengning Ding, Xi Ling, Daiqian Xie, Ning Lu, Changjin Wan, Qihua Xiong, Weigao Xu
Summary: A spontaneous and stochastic polarity-flipping phenomenon has been discovered in monolayer WSe2, triggered by fluctuating carrier flows from or to the adjacent WS2 monolayer. This leads to switching between negative and positive correlations between the emission intensities of WS2 and WSe2 in the heterobilayer.
Article
Spectroscopy
Yongfeng Wan, Dongwei Wang, Bo Li, Yuliang Liu, Lixia Zhu, Yu Wan, Qi Li, Hang Yin, Ying Shi
Summary: Stimuli-responsive luminogens with aggregation-induced emission and excited state intramolecular proton transfer (ESIPT) properties have a wide range of applications. In this study, a simple pressure-induced method was used to restrict the twisted intramolecular charge transfer (TICT) behavior, resulting in fluorescence enhancement and color shifts under high pressure. The inhibition of TICT was achieved by damaging the ESIPT process and restricting the rotation of a specific molecule. This approach offers a new strategy for the development of stimulus-responsive materials.
SPECTROCHIMICA ACTA PART A-MOLECULAR AND BIOMOLECULAR SPECTROSCOPY
(2023)
Article
Chemistry, Applied
Catia I. C. Esteves, Luis F. B. Fontes, A. Filipa N. Borges, Joao Rocha, Artur M. S. Silva, Samuel Guieu
Summary: It is discovered that 2'-aminochalcones with a strong push-pull character exhibit dual emission due to the Excited State Intramolecular Proton Transfer (ESIPT) between ketoenamine and enol-imine tautomers. The strength of hydrogen bonds is correlated with the tautomerization energy gap, depending on the electron donating or electron withdrawing group on the amine.
Article
Chemistry, Physical
Young Mo Sung, Eun Suk Kwon, Yusuke Makida Maruyama, Youngsik Shin, Soo-Ghang Ihn, Jong Soo Kim, Hyeonho Choi, Hyo Sug Lee, Jung-Hwa Kim, Joonghyuk Kim, Soohwan Sul
Summary: Intramolecular charge transfer (ICT) and twisted intramolecular charge transfer (TICT) were studied in pyrene derivatives using time-resolved spectroscopy. The fluorescence behavior, including fluorescence intensity, was found to be solvent-dependent and can be modulated through structural modifications.
PHYSICAL CHEMISTRY CHEMICAL PHYSICS
(2022)
Article
Biochemistry & Molecular Biology
Yan Zhao, Miaomiao He, Lei Xu, Chi Zhang, Liulong Guo, Weixu Feng, Hongxia Yan
Summary: This study developed a non-conjugated fluorescent polymer based on hyperbranched polysiloxane (HBPSi) with twisted intramolecular charge transfer (TICT) and aggregation-induced emission (AIE) features. HBPSi-Cys exhibits dual-state emission and a large Stokes shift, making it suitable as a fluorescent probe and smart fluorescent biomaterial. The introduction of a sulfur atom allows for the design of a new functional material.
Article
Chemistry, Multidisciplinary
Chao Wu, Weiqiang Liu, Kai Li, Gang Cheng, Jinfan Xiong, Teng Teng, Chi-Ming Che, Chuluo Yang
Summary: Intramolecular through-space charge-transfer (TSCT) excited states are utilized for developing thermally activated delayed fluorescence (TADF) emitters, with a series of precisely controlled TSCT emitters designed through alignment optimization of donor and acceptor segments. By increasing intramolecular pi-pi interactions, radiative decay rate of the lowest singlet excited state (S-1) is progressively enhanced with suppression of nonradiative decay, leading to significantly improved photoluminescence quantum yields of up to 0.99 in doped thin films. A high-efficiency electroluminescence device achieves a maximum external quantum efficiency (EQE) of 23.96% and maintains >20% at a brightness of 1000 cd m(-2), highlighting the importance of conformation control for high-efficiency intramolecular exciplex emitters.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2021)
Article
Spectroscopy
Shaoheng Li, Na Shi, Mingyu Zhang, Zhaokang Chen, Daichuan Xia, Qingchuan Zheng, Guodong Feng, Zhiguang Song
Summary: Molecules with Aggregation-Induced Emission (AIE) effects have potential applications in the field of solid luminescent materials. This study synthesized a new benzotriazole derivate with both twisted intramolecular charge transfer (TICT) and AIE effects, suitable for proton detection.
SPECTROCHIMICA ACTA PART A-MOLECULAR AND BIOMOLECULAR SPECTROSCOPY
(2022)
Article
Chemistry, Applied
Jae moon Lee, Sim bum Yuk, Jin woong Namgoong, Jae pil Kim
Summary: This study demonstrated the mechanism of mechanofluorochromism based on D-A complexes by designing and synthesizing a specific compound and investigating the effect of external stimuli on molecular geometry. Experimental results showed a relationship between ICT and RIR characteristics and molecular geometry, highlighting the importance of geometry in determining emission properties.
Article
Chemistry, Multidisciplinary
Chun-Hsiang Wang, Zong-Ying Liu, Chun-Hao Huang, Chao-Tsen Chen, Fan-Yi Meng, Yu-Chan Liao, Yi-Hung Liu, Chao-Che Chang, Elise Y. Li, Pi-Tai Chou
Summary: This study presents experimental observations on the excited-state intramolecular proton transfer (ESIPT) reaction of the thiol proton in room-temperature solution for the first time. The results indicate that all studied thiols undergo thermally favorable ESIPT, and the diethylamino electron-donating group extends pi-electron delocalization, primarily in the pi pi* configuration of the S-1' state, exhibiting significant tautomer emission.
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY
(2021)
Article
Chemistry, Multidisciplinary
Kaia. R. R. Parenti, Rafi Chesler, Guiying He, Pritam Bhattacharyya, Beibei Xiao, Huaxi Huang, Daniel Malinowski, Jocelyn Zhang, Xiaodong Yin, Alok Shukla, Sumit Mazumdar, Matthew. Y. Y. Sfeir, Luis. M. M. Campos
Summary: Quantum interference is crucial in organic molecular electronics and can be predicted using graphical models. In this study, we investigated its application in intramolecular singlet-fission compounds and found that destructive interference leads to slower triplet pair formation.
Article
Chemistry, Organic
Daniel Pecorari, Andrea Mazzanti, Stefano Gianvittorio, Simone Foschi, Stefano Stagni, Valentina Fiorini, Michele Mancinelli
Summary: The stereodynamic properties of amino bis-mesityl-boranes bearing carbazole and benzocarbazole as donor heterocycles were investigated through dynamic NMR analysis and DFT calculations. Different pi-contributions to the B-N bond were found for the two series, leading to pronounced variations in the fluorescence spectra.
ORGANIC CHEMISTRY FRONTIERS
(2021)
Article
Chemistry, Multidisciplinary
Xian Wang, Yingqi Cui, Li Zhang, Mingli Yang
Summary: The study demonstrates the tunable interlayer conductance of graphene by vertical electric field, controlled by interlayer stacking, distance, disc size, and field strength. Analysis of polarizability decomposition scheme reveals the significant role of the middle layer in shielding and promoting interlayer electron flow, with effects varying with twist angle and disc size.
Article
Chemistry, Physical
Riya Sinha, Arunavo Chatterjee, Pradipta Purkayastha
Summary: Daunomycin is a chemotherapy drug used in leukemia treatment, and a delivering agent is needed to transport it to the therapeutic target. It has been found that ultrasmall graphene quantum dots can help Daunomycin rapidly penetrate the cell membrane.
JOURNAL OF PHYSICAL CHEMISTRY B
(2022)
Article
Chemistry, Physical
Dipanjan Halder, Pradipta Purkayastha
Summary: This study investigates the changes in the excited state intramolecular proton transfer (ESIPT) of 3-HF caused by cationic surfactant-induced compaction of DNA.
Article
Genetics & Heredity
Sana Munquad, Tapas Si, Saurav Mallik, Asim Bikas Das, Zhongming Zhao
Summary: In this study, a deep learning framework based on a convolutional neural network was developed for the accurate identification of GBM subtypes. The deep learning model outperformed traditional machine learning algorithms in subtype identification. The study also identified genotype-phenotype relationships of GBM subtypes and subtype-specific predictive biomarkers, providing potential diagnostic and treatment options.
FRONTIERS IN GENETICS
(2022)
Article
Biochemical Research Methods
Arunavo Chatterjee, Ruturaj, Manas Pratim Chakraborty, Sukhendu Nandi, Pradipta Purkayastha
Summary: Lateral heterogeneity in cell membranes, such as the formation of lipid rafts, plays important roles in cellular processes. This study aims to develop a new, simple, cost-effective, and bio-friendly lipid raft marker using hydrophobic, fluorescent, photostable, and non-cytotoxic carbon dots.
ANALYTICAL AND BIOANALYTICAL CHEMISTRY
(2022)
Article
Chemistry, Multidisciplinary
Arunavo Chatterjee, Pradipta Purkayastha
Summary: This article discusses the impact of chemical interfaces on the dynamics of small-molecule guests, and explores specific and interesting phenomena and future prospects.
Article
Chemistry, Physical
Arunavo Chatterjee, Ankit Kumar Sharma, Souvik Pramanick, Odhavia Sahil Jaykishan, Pradipta Purkayastha
Summary: Ion-aided inclusion of protein-coated nanoparticles inside liposomal membranes is commonly used in drug delivery. The stability of liposomes depends on the nature of the interaction. In this study, a niosomal membrane made from a 1:1 Triton X-100(TX-100)/cholesterol mixture was used to incorporate BSA-coated AgNCs to provide stability driven by the specific interaction between TX-100 and BSA. This composite showed sensitivity to external stimuli and was used to observe and analyze the dynamics of FRET between AgNCs and a coumarin dye.
JOURNAL OF PHYSICAL CHEMISTRY C
(2023)
Article
Chemistry, Physical
Bishnu Das, Arunavo Chatterjee, Pradipta Purkayastha, Parna Gupta
Summary: Twotrinuclear cyclometalated iridium(III)-based complexes of M-Ir-M (M = Re, Ir) type were designed to exhibit different electron distributions and demonstrate photoinduced intramolecular electron transfer (PIIET) with various lifetime of radicals. The amine ends of these complexes can also reduce gold salt to generate Au atomistic nanoclusters (AuNCs) and induce excited state intersystem charge transfer (ESICT) when excited with radiation. This phenomenon of converting PIIET to ESICT in a coordination complex coupled with a noble metal nanocluster is unique and shows potential for energy device applications.
JOURNAL OF PHYSICAL CHEMISTRY C
(2023)
Article
Chemistry, Physical
Subham Burai, Sapna Waghmare, Arunavo Chatterjee, Pradipta Purkayastha, Somen Mondal
Summary: The chiral properties of nanoscale materials and their interactions with protein-based biopolymers offer new opportunities for spintronic applications. In this study, we investigated the chiroptical effect in a chiral carbon dot-doped biopolymer film. We observed a spin selectivity of charge carriers, indicating the potential for chiral-sensitized bioelectronic devices and chiral electrode fabrication. These advancements in biopolymer-based chiral electronics have important implications in biosensing, drug delivery, and biomedical applications.
JOURNAL OF PHYSICAL CHEMISTRY C
(2023)
Article
Nanoscience & Nanotechnology
Ishani Mukherjee, Hrishika Dekate, Pradipta Purkayastha
Summary: Noncanonical DNA segments, including i-motifs, are formed by DNA molecules that do not follow the Watson-Crick rules. i-motifs are four-stranded DNA secondary structures that consist of cytosine-rich sequences. These structures are stabilized by intercalated C:C+ base pairs in acidic pH conditions. Recent studies have observed the formation and dissolution of i-motifs in living cells, opening up new possibilities for investigation. Researchers have synthesized ultrasmall carbon nanodots with folic acid-derived molecules that can interfere with the breathing phenomenon of DNA and regulate i-motif formation. This regulation could have significant implications for gene regulation and cancer treatments.
ACS APPLIED NANO MATERIALS
(2023)
Article
Chemistry, Physical
Ankit Kumar Sharma, Arunavo Chatterjee, Pradipta Purkayastha
Summary: Caffeic acid phenethyl ester (CAPE) is a widely studied substance with various biological and pharmaceutical applications, including antimicrobial, antiviral, anti-inflammatory, and anticancer activities. This present study highlights the overlooked photoinduced cis/trans isomerization property of CAPE and provides detailed insights into its photophysical changes and related physical parameters.
CHEMICAL PHYSICS IMPACT
(2023)
Article
Chemistry, Physical
Manish Mukherjee, Arunavo Chatterjee, Soumyadip Bhunia, Pradipta Purkayastha
Summary: In this study, 3D cubic CsPbBr3 perovskite nanocrystals were converted into 2D-platelets of unusually large size through ligand-ligand hydrophobic interactions. The planar perovskite-derivatives act as an exciton donor to the embedded AuNCs through photoinduced electron transfer (PET), which is controlled by the optimum surfactant chain length. The findings of this study can potentially contribute to the development of metal nanocluster-based hybrid 2D perovskite-derived platelets for optoelectronic applications.
JOURNAL OF PHYSICAL CHEMISTRY LETTERS
(2023)
Article
Chemistry, Multidisciplinary
Riya Sinha, Odhavia Sahil Jaykishan, Pradipta Purkayastha
Summary: Resonance energy transfer from graphene quantum dots (GQDs) to tetrakis(m-nitrophenyl) porphyrin (TNPP) was achieved, leading to efficient generation of singlet oxygen with high quantum yield.
Article
Materials Science, Multidisciplinary
Pradip Pattanayak, Arnab Nandi, Sourav Kanti Seth, Pradipta Purkayastha
Summary: The three possible emissive states of pyrene and its aggregates can be controlled by synthesizing three different donor-acceptor pyrene derivatives. The design of the donor units allows for different emissive states based on the molecular planarity and electron density. Spectroscopic and crystal structure analysis reveals that J aggregation and reduction of π-π interaction play important roles in generating long-lived room temperature phosphorescence in crystals. A micelle-assisted microcrystallization strategy was developed to achieve pure organic room temperature phosphorescence in water.
JOURNAL OF MATERIALS CHEMISTRY C
(2023)
Article
Chemistry, Physical
Pradip Pattanayak, Arnab Nandi, Pradipta Purkayastha
Summary: By utilizing polymorph engineering, the production of both thermally activated delayed fluorescence and room-temperature phosphorescence has been regulated through a single polymorphic molecule. Thermodynamically controlled macrocrystals exhibit delayed fluorescence, while kinetically controlled microcrystals display phosphorescence.
CHEMISTRY OF MATERIALS
(2023)
Article
Chemistry, Multidisciplinary
Arnab Nandi, Pradip Pattanayak, Pradipta Purkayastha
Summary: This research investigates the influence of micelle charge and length on fluorescence performance, and finds that the fluorescence quantum yield is significantly enhanced with excellent thermal stability beyond the critical micellar concentration.
NEW JOURNAL OF CHEMISTRY
(2023)
Article
Chemistry, Physical
Wiem Bouali, Muejgan Yaman, Nurgul Seferogu, Zeynel Seferogu
Summary: Novel chemosensors, including coumarin hydrazide, were synthesized and demonstrated the ability to detect cyanide ions through absorption and fluorescence turn-off response. The reaction mechanism between the sensors and the ions was determined through experimental and theoretical studies. The sensors exhibited high detection ability and effectiveness.
JOURNAL OF PHOTOCHEMISTRY AND PHOTOBIOLOGY A-CHEMISTRY
(2024)
Article
Chemistry, Physical
Parinaz Abdollahian, Hassan Heidari, Soheila Hassanzadeh, Mohammad Hasanzadeh
Summary: This study successfully synthesized various types of thiolated-graphene quantum dots (GQDs) and utilized them in a one-droplet microfluidic paper-based analytical device for the simultaneous multi-sensing of heavy metal ions. The GQDs were functionalized and stabilized on the surface of hydrophobic fiber-glass, enabling colorimetric chemosensing of ions including iron, copper, cobalt, mercury, chrome, manganese, and nickel. The results were confirmed using fluorescence spectrometry, and the platform showed potential for facile metal ion detection in human urine models and environmental fluids.
JOURNAL OF PHOTOCHEMISTRY AND PHOTOBIOLOGY A-CHEMISTRY
(2024)
Article
Chemistry, Physical
S. L. Barrett, C. Meyer, E. Cwiklik, V Fieglein, M. Burns, J. Guerrero, W. J. Brittain
Summary: Laboratory illumination is strong enough to create a photostationary state (PSS) of amphiphilic azo-benzene compounds in water. The [cis]PSS/[trans]PSS ratios were observed to be 0.33-1.2 in D2O and 0.37-3.8 in dimethyl sulfoxide-d6. ortho-Fluoroazobenzene amphiphiles show higher cis-isomer concentration at equilibrium compared to non-fluorinated compounds due to differences in optical absorption profiles. The kinetics of isomerization were measured using UV-Vis spectroscopy and the ratio of trans-to-cis rates does not directly correlate with the observed PSS. The half-life for PSS formation is 40 minutes for fluorinated compounds and 80 minutes for non-fluorinated compounds.
JOURNAL OF PHOTOCHEMISTRY AND PHOTOBIOLOGY A-CHEMISTRY
(2024)
Article
Chemistry, Physical
Jalil Khodayari, Karim Zare, Omid Moradi, Mohammadreza Kalaee, Niyaz Mohammad Mahmoodi
Summary: In this study, an eco-friendly biocomposite (CMC/MIL/CuO) was synthesized and characterized, and its ability to decolorize Acid Blue 92 dye was investigated. The results showed that CMC/MIL/CuO can be used as a suitable photocatalyst for dye decolorization.
JOURNAL OF PHOTOCHEMISTRY AND PHOTOBIOLOGY A-CHEMISTRY
(2024)
Article
Chemistry, Physical
Bo Ma, Qian Xu, Huajun Yao, Yalin Chen, Yiyang Wang, Yunfei Yang, Hongfang Shen, Youjun Lu
Summary: This study designed an integrated structure of Cu2O@Au/Cu2O heterostructure particles, which achieved significantly enhanced photocatalytic performance by simultaneously considering the integrated structural characteristics and localized surface plasmon resonance (LSPR) effect. Experimental characterization and theoretical simulation confirmed the three-in-one synergy of the integrated heterostructure, including the LSPR effect of Au nanoparticles, the light scattering based on core-shell heterostructure, and the effective charge separation based on inter-embedded heterostructure. The concept of integrated heterostructure cooperated with LSPR effect provides a new strategy for designing future catalysts.
JOURNAL OF PHOTOCHEMISTRY AND PHOTOBIOLOGY A-CHEMISTRY
(2024)
Article
Chemistry, Physical
Robert G. H. Marks, Sarah P. Rockel, Klaus Kerpen, Holger Somnitz, Philipp R. Martin, Maik A. Jochmann, Torsten C. Schmidt
Summary: This study investigated the pH-dependent photolysis of phosphonates in aqueous solutions and analyzed the transformation products. The results showed that the photolysis rate of phosphonates was influenced by pH and light conditions. Furthermore, the carbon kinetic isotope effects varied for different types of phosphonates.
JOURNAL OF PHOTOCHEMISTRY AND PHOTOBIOLOGY A-CHEMISTRY
(2024)
Article
Chemistry, Physical
T. M. Naren Vidaarth, S. Surendhiran, K. S. G. Jagan, S. Savitha, K. S. Balu, A. Karthik, B. Kalpana
Summary: In this study, magnesium oxide nanoparticles were synthesized using plant seed extracts, which exhibited excellent performance in removing dyes from textile water bodies. These nanoparticles also showed strong antibacterial and antioxidant properties.
JOURNAL OF PHOTOCHEMISTRY AND PHOTOBIOLOGY A-CHEMISTRY
(2024)
Article
Chemistry, Physical
Mikhail Yu. Ovchinnikov, Vyacheslav A. Antipin, Sergey L. Khursan
Summary: In this study, the recombination of separated ion-radical states (SIRS) in PAPh films was analyzed, and it was found that the contribution of X-SIRS recombination to total luminescence varies with different environments. It was also shown that the recombination of labile SIRS is independent of the nature of the atmosphere. The study theoretically substantiated that SIRS recombination can occur via the transfer of both positive and negative charges, and the efficiency of thermal activation of recombination processes depends on the ratio of radiant and conductive channels of energy transfer.
JOURNAL OF PHOTOCHEMISTRY AND PHOTOBIOLOGY A-CHEMISTRY
(2024)
Article
Chemistry, Physical
Sumaira Naeem, Tayyaba Mubashir, Mudassir Hussain Tahir, Jawayria Najeeb, Ahmed Z. Dewidar, Hosam O. El-ansary, Silas Lagat, Anthony Pembere
Summary: This study presents an alternative methodology using machine learning for the selection of novel organic molecules to develop high-performance organic solar cell devices.
JOURNAL OF PHOTOCHEMISTRY AND PHOTOBIOLOGY A-CHEMISTRY
(2024)
Article
Chemistry, Physical
D. Thirumoolan, S. Ragupathy, S. Renukadevi, P. Rajkumar, Rajakumar S. Rai, R. M. Saravana Kumar, Imran Hasan, Mani Durai, Young-Ho Ahn
Summary: In this study, the photodegradation of brilliant green dye was studied in relation to the comparative photocatalytic activity of pure ZnO and Ni-doped ZnO/CSAC. The Ni-doped ZnO/CSAC showed a higher photocatalytic degradation rate under visible light irradiation, suggesting its potential as an effective wastewater treatment material.
JOURNAL OF PHOTOCHEMISTRY AND PHOTOBIOLOGY A-CHEMISTRY
(2024)
Article
Chemistry, Physical
Ajmal Khan, Zhidong Chang, Wenjun Li, Xiaohui Ma, Mei Dong, Liang Geng, Ghulam Yasin, Shuaib Khan, Hira Anwar
Summary: Due to its functional structure and tunable shape, 2D zeolitic imidazole framework (ZIFs) have gained significant interest in various fields. In this study, thin ZIF-8 sheets were prepared using a mixed solvent and then delaminated into single layers through physical sonication. These hexagonal sheets exhibited high stability and controlled morphology, and showed excellent performance in dye degradation compared to 3D ZIF-8 crystals.
JOURNAL OF PHOTOCHEMISTRY AND PHOTOBIOLOGY A-CHEMISTRY
(2024)
Article
Chemistry, Physical
Vitaly A. Podshibyakin, Evgenii N. Shepelenko, Leonid D. Popov, Tatyana M. Valova, Anton O. Ayt, Lyudmila G. Kuzmina, Anton V. Lisovin, Oleg N. Burov, Mikhail E. Kletskii, Alexander D. Dubonosov, Vladimir A. Bren
Summary: Bifunctional hybrids containing photochromic indolyl(thienyl) diarylethenes and an ionochromic rhodamine moiety connected by a dimethylene spacer were synthesized. These hybrids exhibit absorption at 450-455 nm and fluorescence at 560 nm in toluene. UV light triggers ring-closed non-fluorescent diarylethene formation, which can be reversed under visible light or in the dark. In the presence of H+ cation, a naked eye effect is observed with the opening of the rhodamine-spirolactam ring and a pink-crimson coloration at 561 nm accompanied by intense long-wavelength emission at 586 nm. This process is reversible by exposure to triethylamine, as confirmed by NMR experiments. The light-induced isomerizations and proton-induced transformations were explained using computational methods. Reversible switching of fluorescent properties can be achieved by light irradiation and proton.
JOURNAL OF PHOTOCHEMISTRY AND PHOTOBIOLOGY A-CHEMISTRY
(2024)
Article
Chemistry, Physical
Majid Sharifi-Rad, Hazem S. Elshafie, Pawel Pohl
Summary: The study investigated the synthesis of silver nanoparticles using Lallemantia royleana leaf extract, characterized their physico-chemical properties, and evaluated their biopharmaceutical and catalytic applications. The synthesized nanoparticles showed good stability and exhibited higher antioxidant, antimicrobial, anti-inflammatory, anti-arthritic, and cytotoxic activities compared to the leaf extract. These results provide a promising green synthesis route for silver nanoparticles with potential biomedical and catalytic applications.
JOURNAL OF PHOTOCHEMISTRY AND PHOTOBIOLOGY A-CHEMISTRY
(2024)
Article
Chemistry, Physical
Meera Moydeen Abdul Hameed, Badr M. Thamer
Summary: Security encoding using photochromism is an effective method for creating authentication substrates. A unique photochromic ink has been developed that emits light continuously under UV rays and darkness. The ink is produced by dispersing lanthanidedoped aluminate nanoparticles in a polymer binder. The resulting composite ink can be used to create transparent films on paper, and the stamped patterns become visible under UV rays, changing from colorless to green.
JOURNAL OF PHOTOCHEMISTRY AND PHOTOBIOLOGY A-CHEMISTRY
(2024)
Article
Chemistry, Physical
Monika Lamoria, Rita Kakkar, Marilyn Daisy Milton
Summary: Four novel water-soluble benzimidazolium and bis-benzimidazolium salts with a fluorophore-spacer-receptor design were synthesized and demonstrated to selectively detect Fe3+ ions with large Stokes shifts. The binding mechanism and detection performance were investigated through theoretical and experimental studies.
JOURNAL OF PHOTOCHEMISTRY AND PHOTOBIOLOGY A-CHEMISTRY
(2024)