Article
Nanoscience & Nanotechnology
Ewa Kowalska, Saulius Juodkazis, Patrycja Henkiel, Damian Kowalski
Summary: This study demonstrates the electrochemical and plasmonic features of gold structures grown in anodic TiO2 nanotubes. The electroreduction of Au+ species from a potassium dicyanoaurate electrolyte leads to the formation of a gold/titania interface at the outer shell of the nanotubes. This unique configuration allows for the development of a specific shape of gold nanopore array, which exhibits enhanced light absorption and scattering due to surface plasmon resonance.
ACS APPLIED NANO MATERIALS
(2022)
Article
Chemistry, Multidisciplinary
Ziyong Chen, Vivian Wing-Wah Yam
Summary: This study presents a novel class of molecular orbital images for predicting excited-state energetics. By representing hole and particle states as channels, the model achieves excellent prediction accuracy for both singlet and triplet states.
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY
(2023)
Article
Astronomy & Astrophysics
Meina Liu, Huiting Ma, Yidan Geng, Patrick Palmeri, Pascal Quinet, Zhenwen Dai
Summary: In this study, the natural radiative lifetimes and branching fractions of Re ii in certain energy levels were measured and calculated. These radiative parameters contribute to the atomic database of Re ii and are valuable for astrophysicists in evaluating the abundance of Re in stars.
ASTROPHYSICAL JOURNAL SUPPLEMENT SERIES
(2022)
Article
Chemistry, Medicinal
Xue-Li Hao, Ai -Min Ren, Liang Zhou
Summary: Hydrogen sulfide (H2S) is important for physiological and pathological processes, but abnormal levels can cause diseases. Researchers investigated the luminous mechanism of turn-on probe for H2S monitoring and explored the effect of geometric modifications on optical properties. They found that introducing electron-withdrawing groups in benzopyran can suppress molecular skeleton vibration and improve two-photon absorption properties. A potential material for biological imaging and H2S detection with distinguishable spectra, high luminous efficiency, and large two-photon absorption cross section was obtained.
JOURNAL OF CHEMICAL INFORMATION AND MODELING
(2023)
Article
Chemistry, Medicinal
Xue-Li Hao, Ai-Min Ren, Liang Zhou
Summary: Hydrogen sulfide (H2S) has important physiological and pathological roles, but abnormal levels can cause diseases. Researchers have explored the mechanism of a turn-on probe for H2S monitoring and investigated the effect of geometric modifications on optical properties. They found that introducing electron-withdrawing substituent groups in benzopyran can suppress molecular skeleton vibration and improve two-photon absorption (TPA) ability, making it a potential material for biological imaging and H2S detection.
JOURNAL OF CHEMICAL INFORMATION AND MODELING
(2023)
Article
Chemistry, Multidisciplinary
Parimah Aminfar, Goonay Yousefalizadeh, Emily Steele, Juan Chen, Gang Zheng, Kevin G. Stamplecoskie
Summary: Aqueous gold nanoclusters (AuNCs) have potential applications in biomedical imaging and therapy due to their unique electronic structures. However, their optical impurity and polydispersity pose challenges for isolation of the most stable structure and potential clinical applications. This study reports optically pure Au16L14 clusters, assessed by fluorescence excitation-emission matrix (EEM) spectroscopy and parallel factor (PARAFAC) analysis. The reactivity of the excited state with molecular oxygen was also investigated, showing that Au16L14 clusters generate type I reactive oxygen species (ROS), making them effective sensitizers for photodynamic therapy.
Article
Chemistry, Physical
Jian Zhu, Shu-min Zhao
Summary: This study investigated the local dielectric constant-dependent fluorescence quenching of gold nanoshell using quasi-static electrodynamics theory and FRET. It was found that the quenching efficiency is related to the dielectric constants of the outer surrounding and inner core, and can be fine tuned by altering the local dielectric environment.
Article
Spectroscopy
P. A. S. Randi, D. F. Pastega, M. H. F. Bettega, N. C. Jones, S. V. Hoffmann, S. Eden, A. Souza Barbosa, P. Limao-Vieira
Summary: Absolute cross-section values of gas-phase formic acid in the VUV range have been measured and analyzed, revealing previously unreported vibronic features and active vibrational modes. The photoabsorption measurements also provide information on the photolysis lifetime of formic acid at different altitudes. The combination of experimental and theoretical methods allows for a comprehensive understanding of the electronic transitions and potential energy curves.
SPECTROCHIMICA ACTA PART A-MOLECULAR AND BIOMOLECULAR SPECTROSCOPY
(2023)
Article
Chemistry, Physical
Roman Messner, Wolfgang E. Ernst, Florian Lackner
Summary: Nanoparticles with a layered core@shell@shell structure consisting of three different materials are synthesized by sequential doping in cold helium droplets. The nanoparticles can be functionalized in situ with additional molecules, and the structure of the formed complexes can be studied by observing fluorescence spectra upon laser excitation of RB molecules. This approach can be used for the synthesis and investigation of various combinations of plasmonic metals, intermediate layers, and molecules.
JOURNAL OF PHYSICAL CHEMISTRY LETTERS
(2021)
Article
Chemistry, Physical
Taerin Chung, Sang-Hyuk Lee
Summary: This study investigates the influence of shape on the optical properties of gold nanostars (GNS) and identifies the optimal geometry for surface-enhanced Raman scattering (SERS) applications with different excitation wavelengths.
Article
Materials Science, Multidisciplinary
Yu Chen, Min Liu, Han Huang, Fangping Ouyang
Summary: Multi-path remote-excited SERS can be achieved in a two-dimensional hollow gold nanosheet structure, where a hollow cavity is concentrically located in the middle of a gold nanosheet. The introduction of the hollow cavity allows for modulation of localized surface plasmon resonance and brings in a new coupling effect between different vertices. FDTD simulations show a red-shift of LSPR peak with the increase of cavity size. The remote signal of LSPR scattering can be significantly enhanced, by over 228%, 597%, and 1155% for dual-, triple-, and quad-path-excitation, respectively, under the optimum coupling polarization.
RESULTS IN PHYSICS
(2022)
Article
Engineering, Environmental
Kai Yang, Xinyu Yin, Yuanyang Yan, Kangquan Yang, Pihui Pi, Shouping Xu, Jing Fang, Quanhai Li, Xiufang Wen
Summary: This study reported a novel fluorescence enhanced nanomaterial, where the distance between a plasmonic gold nanorod and cadmium selenide quantum dots could be controlled by adjusting the silica layer thickness, leading to fluorescence enhancement. Experimental results showed that the maximum fluorescence enhancement was achieved when the silica layer thickness was 22 nm, and the material remained colloidal stable even when diluted. This material could be used as an advanced bio-probe for sophisticated medical diagnosis.
CHEMICAL ENGINEERING JOURNAL
(2021)
Article
Chemistry, Multidisciplinary
Sourav Pan, Binaya Kumar Sahu, S. Amirthapandian, Sandip Dhara, Arindam Das
Summary: A seed-mediated synthesis method was used to prepare Au nanorods with different aspect ratios in a single step. The use of halide (Cl) as a growth-defining reagent allowed for unique control of the longitudinal surface plasmon resonance (LSPR), resulting in excellent SERS and photothermal effects.
JOURNAL OF PHYSICS AND CHEMISTRY OF SOLIDS
(2022)
Article
Chemistry, Analytical
Ana-Maria Craciun, Sorina Suarasan, Monica Focsan, Simion Astilean
Summary: This study evaluated the PL properties of different-sized gold nanospheres under one-photon excitation and developed a sensitive homogeneous immunoassay for the detection of PSA. The study showed the potential of synthesized AuNSs as fluorescent probes in bioimaging and bioassays, successfully demonstrating the use of 1PE PL for FCS-based label-free detection of PSA biomarker.
Article
Chemistry, Physical
Ana-Maria Craciun, Laurentiu Susu, Monica Baia
Summary: The intrinsic photoluminescence properties of gold nanorods coated with gelatin were studied using innovative fluorescence spectroscopy combined with fluorescence lifetime imaging microscopy. The study revealed interesting aspect ratio-dependent two-photon excited photoluminescence emission, with a lifetime of around 100 ps. The effect of laser excitation power and wavelength on the photoluminescence performance was evaluated, highlighting the potential application of gelatin-coated gold nanorods as contrast agents for label-free two-photon fluorescence imaging.
JOURNAL OF MOLECULAR STRUCTURE
(2021)
Article
Chemistry, Inorganic & Nuclear
Pramila Selvanathan, Elsa Tufenkjian, Olivier Galangau, Thierry Roisnel, Francois Riobe, Olivier Maury, Lucie Norel, Stephane Rigaut
Summary: We present a bimetallic complex consisting of a ruthenium(II) bisacetylide complex with a photochromic dithienylethene (DTE) acetylide arm and a coordinating bipyridyl, in coordination with Yb(TTA)3 centers. The DTE isomerization is triggered by both UV light absorbed by the DTE unit and 450 nm excitation of the organometallic moiety. The redox behavior of the ruthenium(II) bisacetylide system is fully investigated, revealing a lack of stability of the DTE-closed oxidized state preventing effective redox luminescence switching while the photoswitching of ytterbium(III) NIR emission is fully operational.
INORGANIC CHEMISTRY
(2023)
Article
Chemistry, Inorganic & Nuclear
Amlia Godard, Laura Abad Galan, Jean Rouillon, Shaymaa Al Shehimy, Wassima Tajani, Charlotte Cave, Raluca Malacea-Kabbara, Yoann Rousselin, Pierre Le Gendre, Arnaud Fihey, Mohamed Bendellaa, Benoit Busser, Lucie Sancey, Boris Le Guennic, Christophe Bucher, Olivier Maury, Christine Goze, Ewen Bodio
Summary: Aza-boron-dipyrromethenes (Aza-BODIPYs) are a class of fluorophores with azadipyrromethene (aza-DIPY) ligand rigidified by a boron atom. Complexes of group 13 metals (aluminum and gallium) were synthesized and their properties were investigated. AzaGaDIPY and azaAlDIPY exhibited significant red-shifted fluorescence compared to aza-BODIPY, making them promising for optical medical imaging.
INORGANIC CHEMISTRY
(2023)
Article
Biochemical Research Methods
Marlene Wiart, Clement Tavakoli, Violaine Hubert, Ines Hristovska, Chloe Dumot, Stephane Parola, Frederic Lerouge, Fabien Chauveau, Emmanuelle Canet-Soulas, Olivier Pascual, David P. Cormode, Emmanuel Brun, Helene Elleaume
Summary: The activation of phagocytic cells is important in neurological diseases, and tracking them in the brain using MRI and CT can help understand their role and monitor therapeutic effects. Metal-based contrast agents like gadolinium, gold, and iron can be used for tracking phagocytic cells, but they may have toxicity and accumulation issues. Despite these challenges, early results in patients with neurological diseases are promising.
JOURNAL OF NEUROSCIENCE METHODS
(2023)
Article
Chemistry, Applied
Melinda Gal, Castelia Cristea, Ana Maria Craciun, Alexandru Turza, Lucian Barbu-Tudoran, Brem Balazs, Tamas Lovasz, Luminita Silaghi-Dumitrescu, Luiza Ioana Gaina
Summary: This study reports the synthesis and structural characterization of four new phenothiazine-carboxylate salts and their use as contrast agents in fluorescent electrospun polyvinylpyrrolidone nanomaterials for latent fingerprint detection. The optical properties of the new fluorophores and nanomaterials were evaluated, showing intense and uniform fluorescence in the solid state. Scanning electron microscopy investigations revealed the nanometric size of the nanomaterials. These newly synthesized nanomaterials showed promising results in the detection and visualization of latent fingerprints on various surfaces.
Article
Chemistry, Multidisciplinary
Yige Yan, Adel Mesbah, Lhoussain Khrouz, Corinne Bouillet, Chantal Lorentz, Nicholas Blanchard, Anne C. Berends, Marie Anne van de Haar, Frederic Lerouge, Michael R. Krames, Ovidiu Ersen, Frederic Chaput, Stephane Parola
Summary: In this paper, the synthesis of ultra-small YPO4-YAG:Ce nanocomposite phosphor particles with high quantum yield (QY) of 53% and a particle size of approximately 10 nm is reported. The localization of phosphate and extra yttrium entities with respect to cerium centers in the YAG host has been determined using fine structural analysis techniques. The correlation between the additive-induced physico-chemical environment change around cerium centers and the increasing photoluminescence performance has been suggested based on experimental data and crystallographic simulation studies.
Article
Materials Science, Multidisciplinary
Antonio Carone, Pablo Mariani, Anthony Desert, Stephane Parola
Summary: Investigated the assembly of chiral plasmonic particles without using a chiral templating agent. Chiral core-shell Au@Ag and Au@Au particles were assembled in a controlled way by lowering the surfactant concentration in solution. The assembly led to pseudo-linear structures revealed by electron microscopy, and the plasmonic responses were characterized by circular dichroism (CD) and UV-Vis-NIR spectroscopies.
ADVANCED OPTICAL MATERIALS
(2023)
Article
Chemistry, Physical
Istvan Szekely, Zoltan Kovacs, Mihai Rusu, Tamas Gyulavari, Milica Todea, Monica Focsan, Monica Baia, Zsolt Pap
Summary: Developing highly efficient Au/TiO2/WO3 heterostructures with applications in heterogeneous photocatalysis and surface-enhanced Raman spectroscopy is of paramount significance. Au/TiO2/WO3 heterostructures were obtained via modified Turkevich-Frens synthesis methods and were characterized by various techniques. The structural features, such as WO3 crystalline phases and TiO2 surface defects, were found to be crucial for enhancing the photocatalytic activity.
Article
Chemistry, Physical
Jakub Kusz, Cedric Boissiere, Dris Ihiawakrim, Ovidiu Ersen, Clement Sanchez, Stephane Parola
Summary: This study focuses on the molecular-level understanding of the self-assembling processes in hybrid mesoporous films using model precursors. Ordered mesoporous silica thin films are prepared by the co-condensation sol-gel process, with the use of an ionic surfactant as a template. The influence of parameters such as alkyl chain length, concentration, and relative humidity on the film mesostructure is evaluated, and the relationship between these parameters and the mesophase arrangement, pore size distribution, porosity, and Young's modulus is established.
CHEMISTRY OF MATERIALS
(2023)
Article
Biophysics
Vlad Cucuiet, Maria Iliut, Monica Potara, Klara Magyari, Septimiu Tripon, Olga Soritau, Dana Maniu, Simion Astilean, Monica Focsan
Summary: In this work, a gelatin-based method was developed for fabrication of reduced graphene oxide (rGO-GEL) with high stability and biocompatibility. Gelatin was used not only to enhance the biocompatibility of rGO, but also to prevent the aggregation of graphene oxide nanosheets during reduction process. Multiple spectroscopic analyses and microscopy observations confirmed the successful reduction process and the attachment of gelatin to rGO. The cellular toxicity test demonstrated the non-toxicity of rGO-GEL nanoflakes for melanoma B16-F10 cells. The nanoflakes were also used for cellular imaging.
COLLOIDS AND SURFACES B-BIOINTERFACES
(2023)
Article
Biochemistry & Molecular Biology
Gabriel Marc, Anca Stana, Mihaela Tertis, Cecilia Cristea, Alexandra Ciorita, Stefan-Mihai Dragan, Vlad-Alexandru Toma, Raluca Borlan, Monica Focsan, Adrian Pirnau, Laurian Vlase, Smaranda Oniga, Ovidiu Oniga
Summary: Oxidative stress is associated with various diseases, and developing efficient antioxidants could be beneficial in preventing or improving these conditions. By utilizing structure optimization and computational studies, we designed several catechol derivatives with enhanced antioxidant potential. These compounds were synthesized, characterized, and evaluated for their antioxidant activity through various tests. The results showed that the final compounds had excellent antioxidant properties, consistently outperforming the reference compounds. Additionally, the compounds' electrochemical behavior and cytotoxicity were also studied and correlated well with the antioxidant activity. Compound 7b, with two catechol moieties in its structure, exhibited the highest antioxidant activity.
INTERNATIONAL JOURNAL OF MOLECULAR SCIENCES
(2023)
Article
Pharmacology & Pharmacy
Adriana Cristina Urcan, Adriana Dalila Criste, Karina Ioana Szanto, Razvan Stefan, Marius Zahan, Adriana Sebastiana Musca, Monica Focsan, Ramona Flavia Burtescu, Neli Kinga Olah
Summary: In this study, a green synthesis of colloidal silver nanoparticles was developed using bee bread extracts as reducing and stabilizing agents. The newly synthesized nanoparticles showed good antioxidant and antibacterial activity, indicating their potential as functional food for humans.
Meeting Abstract
Biophysics
Ioan Turcu, Simion Astilean, Monica Focsan, Ana-Maria Craciun, Alina Vasilescu, Daniel Marconi, Alia Colnita, Monica Potara
EUROPEAN BIOPHYSICS JOURNAL WITH BIOPHYSICS LETTERS
(2023)
Article
Chemistry, Multidisciplinary
Antonio Carone, Samuel Emilsson, Pablo Mariani, Anthony Desert, Stephane Parola
Summary: This study aimed to understand and predict the colloidal stability of colloidal gold nanostructures composed of AuNPs and CTAB. It was found that the shape of nanoparticles had an impact on the overall stability, with the presence of sharp tips being the source of instability. A metastable area was systematically observed in the stability diagrams, where the system aggregated in a controlled way while maintaining colloidal stability. By combining strategies and using transmission electron microscopy, the behavior of the system in different zones of the diagrams was investigated. Linear structures with good control over the number of particles participating in the assembly and good colloidal stability were obtained by controlling the experimental conditions with the previously obtained diagrams.
NANOSCALE ADVANCES
(2023)
Article
Nanoscience & Nanotechnology
Andreea Campu, Ilinca Muresan, Ana-Maria Craciun, Adriana Vulpoi, Simona Cainap, Simion Astilean, Monica Focsan
Summary: The implementation of metal enhanced fluorescence (MEF) as a detection tool in diagnostic analytical technologies has shown great potential. In this study, a novel microfluidic plasmonic design based on paper was proposed, which utilized gold nanobipyramids (AuBPs) and filter paper to achieve efficient MEF detection. The chip demonstrated portability and flexibility, as well as high-resolution bioimaging capabilities.
ACS APPLIED MATERIALS & INTERFACES
(2023)
Article
Materials Science, Biomaterials
Andreea Campu, Ilinca Muresan, Monica Potara, Diana Raluca Lazar, Florin-Leontin Lazar, Simona Cainap, Dan Mircea Olinic, Dana Maniu, Simion Astilean, Monica Focsan
Summary: This study develops a microfluidic plasmonic chip that can efficiently and accurately detect the cardiac troponin I biomarker via three complementary detection techniques. The study also provides a better understanding of the thermoplasmonic biosensing mechanism using gold nanoparticles' photothermal properties.
JOURNAL OF MATERIALS CHEMISTRY B
(2023)