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Macis S, D'Arco A, Mosesso L, Paolozzi MC, Tofani S, Tomarchio L, Tummala PP, Ghomi S, Stopponi V, Bonaventura E, Massetti C, Codegoni D, Serafini A, Targa P, Zacchigna M, Lamperti A, Martella C, Molle A, Lupi S. Terahertz and Infrared Plasmon Polaritons in PtTe 2 Type-II Dirac Topological Semimetal. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2024; 36:e2400554. [PMID: 38733453 DOI: 10.1002/adma.202400554] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/11/2024] [Revised: 04/18/2024] [Indexed: 05/13/2024]
Abstract
Surface plasmon polaritons (SPPs) are electromagnetic excitations existing at the interface between a metal and a dielectric. SPPs provide a promising path in nanophotonic devices for light manipulation at the micro and nanoscale with applications in optoelectronics, biomedicine, and energy harvesting. Recently, SPPs are extended to unconventional materials like graphene, transparent oxides, superconductors, and topological systems characterized by linearly dispersive electronic bands. In this respect, 3D Dirac and Weyl semimetals offer a promising frontier for infrared (IR) and terahertz (THz) radiation tuning by topologically-protected SPPs. In this work, the THz-IR optical response of platinum ditelluride (PtTe2) type-II Dirac topological semimetal films grown on Si substrates is investigated. SPPs generated on microscale ribbon arrays of PtTe2 are detected in the far-field limit, finding an excellent agreement among measurements, theoretical models, and electromagnetic simulation data. The far-field measurements are further supported by near-field IR data which indicate a strong electric field enhancement due to the SPP excitation near the ribbon edges. The present findings indicate that the PtTe2 ribbon array appears an ideal active layout for geometrically tunable SPPs thus inspiring a new fashion of optically tunable materials in the technologically demanding THz and IR spectrum.
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Affiliation(s)
- Salvatore Macis
- Department of Physics, Sapienza University, Piazzale Aldo Moro 5, Rome, 00185, Italy
| | - Annalisa D'Arco
- Department of Physics, Sapienza University, Piazzale Aldo Moro 5, Rome, 00185, Italy
| | - Lorenzo Mosesso
- Department of Physics, Sapienza University, Piazzale Aldo Moro 5, Rome, 00185, Italy
| | - Maria Chiara Paolozzi
- Department of Physics, Sapienza University, Piazzale Aldo Moro 5, Rome, 00185, Italy
| | - Silvia Tofani
- CNR-IMM, Unit of Rome, Via del Fosso del Cavaliere 100, Rome, 00133, Italy
| | - Luca Tomarchio
- Department of Physics, Sapienza University, Piazzale Aldo Moro 5, Rome, 00185, Italy
| | | | - Sara Ghomi
- CNR-IMM, via C. Olivetti 2, Agrate Brianza (MB), I-20864, Italy
| | - Veronica Stopponi
- CNR-IOM, Area Science Park Strada Statale 14, km 163,5, Basovizza, TS, 34149, Italy
| | - Eleonora Bonaventura
- CNR-IMM, via C. Olivetti 2, Agrate Brianza (MB), I-20864, Italy
- Department of Materials Science, University of Milano-Bicocca, Via Cozzi, 55, Milan, 20125, Italy
| | - Chiara Massetti
- CNR-IMM, via C. Olivetti 2, Agrate Brianza (MB), I-20864, Italy
| | - Davide Codegoni
- STMicroelectronics, via C. Olivetti 2, Agrate Brianza (MB), I-20864, Italy
| | - Andrea Serafini
- STMicroelectronics, via C. Olivetti 2, Agrate Brianza (MB), I-20864, Italy
| | - Paolo Targa
- STMicroelectronics, via C. Olivetti 2, Agrate Brianza (MB), I-20864, Italy
| | - Michele Zacchigna
- CNR-IOM, Area Science Park Strada Statale 14, km 163,5, Basovizza, TS, 34149, Italy
| | | | | | | | - Stefano Lupi
- Department of Physics, Sapienza University, Piazzale Aldo Moro 5, Rome, 00185, Italy
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Adorinni S, Gentile S, Bellotto O, Kralj S, Parisi E, Cringoli MC, Deganutti C, Malloci G, Piccirilli F, Pengo P, Vaccari L, Geremia S, Vargiu AV, De Zorzi R, Marchesan S. Peptide Stereochemistry Effects from p Ka-Shift to Gold Nanoparticle Templating in a Supramolecular Hydrogel. ACS NANO 2024; 18:3011-3022. [PMID: 38235673 DOI: 10.1021/acsnano.3c08004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/19/2024]
Abstract
The divergent supramolecular behavior of a series of tripeptide stereoisomers was elucidated through spectroscopic, microscopic, crystallographic, and computational techniques. Only two epimers were able to effectively self-organize into amphipathic structures, leading to supramolecular hydrogels or crystals, respectively. Despite the similarity between the two peptides' turn conformations, stereoconfiguration led to different abilities to engage in intramolecular hydrogen bonding. Self-assembly further shifted the pKa value of the C-terminal side chain. As a result, across the pH range 4-6, only one epimer predominated sufficiently as a zwitterion to reach the critical molar fraction, allowing gelation. By contrast, the differing pKa values and higher dipole moment of the other epimer favored crystallization. The four stereoisomers were further tested for gold nanoparticle (AuNP) formation, with the supramolecular hydrogel being the key to control and stabilize AuNPs, yielding a nanocomposite that catalyzed the photodegradation of a dye. Importantly, the AuNP formation occurred without the use of reductants other than the peptide, and the redox chemistry was investigated by LC-MS, NMR, and infrared scattering-type near field optical microscopy (IR s-SNOM). This study provides important insights for the rational design of simple peptides as minimalistic and green building blocks for functional nanocomposites.
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Affiliation(s)
- Simone Adorinni
- Chemical Pharmaceutical Sciences Department, University of Trieste, 34127 Trieste, Italy
| | - Serena Gentile
- Chemical Pharmaceutical Sciences Department, University of Trieste, 34127 Trieste, Italy
| | - Ottavia Bellotto
- Chemical Pharmaceutical Sciences Department, University of Trieste, 34127 Trieste, Italy
| | - Slavko Kralj
- Materials Synthesis Department, Jožef Stefan Institute, 1000 Ljubljana, Slovenia
- Department of Pharmaceutical Technology, Faculty of Pharmacy, University of Ljubljana, 1000 Ljubljana, Slovenia
| | - Evelina Parisi
- Chemical Pharmaceutical Sciences Department, University of Trieste, 34127 Trieste, Italy
| | - Maria C Cringoli
- Chemical Pharmaceutical Sciences Department, University of Trieste, 34127 Trieste, Italy
| | - Caterina Deganutti
- Chemical Pharmaceutical Sciences Department, University of Trieste, 34127 Trieste, Italy
| | - Giuliano Malloci
- Physics Department, University of Cagliari, 09042 Monserrato, Cagliari, Italy
| | - Federica Piccirilli
- Elettra Sincrotrone Trieste, 34149 Basovizza, Italy
- Area Science Park, Padriciano 99, 34149 Trieste, Italy
| | - Paolo Pengo
- Chemical Pharmaceutical Sciences Department, University of Trieste, 34127 Trieste, Italy
| | - Lisa Vaccari
- Elettra Sincrotrone Trieste, 34149 Basovizza, Italy
| | - Silvano Geremia
- Chemical Pharmaceutical Sciences Department, University of Trieste, 34127 Trieste, Italy
| | - Attilio V Vargiu
- Physics Department, University of Cagliari, 09042 Monserrato, Cagliari, Italy
| | - Rita De Zorzi
- Chemical Pharmaceutical Sciences Department, University of Trieste, 34127 Trieste, Italy
| | - Silvia Marchesan
- Chemical Pharmaceutical Sciences Department, University of Trieste, 34127 Trieste, Italy
- Unit of Trieste, INSTM, 34127 Trieste, Italy
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Stagno V, Bindi L, Bonechi B, Greaux S, Aulbach S, Irifune T, Lupi S, Marras G, McCammon CA, Nazzari M, Piccirilli F, Poe B, Romano C, Scarlato P. Cubic Fe-bearing majorite synthesized at 18-25 GPa and 1000 °C: implications for element transport, subducted slab rheology and diamond formation. Sci Rep 2023; 13:15855. [PMID: 37740075 PMCID: PMC10516933 DOI: 10.1038/s41598-023-43037-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2018] [Accepted: 09/18/2023] [Indexed: 09/24/2023] Open
Abstract
The chemistry and mineralogy of slabs subducted into lower mantle control slab rheology and impact the deep volatile cycle. It is known that the metamorphism of little-altered oceanic crust results in eclogite rocks with subequal proportions of garnet and clinopyroxene. With increasing pressure, these minerals react to stabilize pyrope-rich tetragonal majoritic garnet. However, some eclogites contain higher proportions of omphacitic clinopyroxene, caused by Na- and Si-rich metasomatism on the ocean floor or during subduction. The mineralogy of such eclogites is expected to evolve differently. Here, we discuss the results of the crystallization products of omphacitic glass at ~ 18 and ~ 25 GPa and 1000 °C to simulate P-T regimes of cold subduction. The full characterization of the recovered samples indicates evidence of crystallization of Na-, Si-rich cubic instead of tetragonal majorite. This cubic majorite can incorporate large amounts of ferric iron, promoting redox reactions with surrounding volatile-bearing fluids and, ultimately, diamond formation. In addition, the occurrence of cubic majorite in the slab would affect the local density, favoring the continued buoyancy of the slab as previously proposed by seismic observations. Attention must be paid to omphacitic inclusions in sublithospheric diamonds as these might have experienced back-transformation from the HP isochemical cubic phase.
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Affiliation(s)
- Vincenzo Stagno
- Dipartimento di Scienze Della Terra, Sapienza Università di Roma, Rome, Italy.
- Istituto Nazionale di Geofisica e Vulcanologia, Rome, Italy.
| | - Luca Bindi
- Dipartimento di Scienze Della Terra, Università di Firenze, Firenze, Italy
| | | | - Steeve Greaux
- Geodynamic Research Center, Ehime University, Matsuyama, Japan
- Earth-Life Science Institute, Tokyo Institute of Technology, Tokyo, Japan
| | - Sonja Aulbach
- Institute for Geosciences, Frankfurt Isotope & Element Research Center (FIERCE), Goethe University, Altenhöferallee 1, 60438, Frankfurt, Germany
| | - Tetsuo Irifune
- Geodynamic Research Center, Ehime University, Matsuyama, Japan
- Earth-Life Science Institute, Tokyo Institute of Technology, Tokyo, Japan
| | - Stefano Lupi
- Department of Physics, Sapienza University of Rome, Rome, Italy
- CNR-IOM, Area Science Park, 34012, Trieste, Italy
| | - Giulia Marras
- Dipartimento di Scienze Della Terra, Sapienza Università di Roma, Rome, Italy
| | | | | | | | - Brent Poe
- Dipartimento di Scienze, Università Di Chieti, Chieti, Italy
| | - Claudia Romano
- Dipartimento di Scienze, Università Di Roma Tre, Rome, Italy
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D'Arco A, Di Fabrizio M, Mancini T, Mosetti R, Macis S, Tranfo G, Della Ventura G, Marcelli A, Petrarca M, Lupi S. Secondary Structures of MERS-CoV, SARS-CoV, and SARS-CoV-2 Spike Proteins Revealed by Infrared Vibrational Spectroscopy. Int J Mol Sci 2023; 24:ijms24119550. [PMID: 37298500 DOI: 10.3390/ijms24119550] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2023] [Revised: 04/28/2023] [Accepted: 05/26/2023] [Indexed: 06/12/2023] Open
Abstract
All coronaviruses are characterized by spike glycoproteins whose S1 subunits contain the receptor binding domain (RBD). The RBD anchors the virus to the host cellular membrane to regulate the virus transmissibility and infectious process. Although the protein/receptor interaction mainly depends on the spike's conformation, particularly on its S1 unit, their secondary structures are poorly known. In this paper, the S1 conformation was investigated for MERS-CoV, SARS-CoV, and SARS-CoV-2 at serological pH by measuring their Amide I infrared absorption bands. The SARS-CoV-2 S1 secondary structure revealed a strong difference compared to those of MERS-CoV and SARS-CoV, with a significant presence of extended β-sheets. Furthermore, the conformation of the SARS-CoV-2 S1 showed a significant change by moving from serological pH to mild acidic and alkaline pH conditions. Both results suggest the capability of infrared spectroscopy to follow the secondary structure adaptation of the SARS-CoV-2 S1 to different environments.
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Affiliation(s)
- Annalisa D'Arco
- Laboratori Nazionali Frascati, National Institute for Nuclear Physics (INFN-LNF), Via E. Fermi 54, 00044 Frascati, Italy
- Department of Physics, University of Rome 'La Sapienza', P.le A. Moro 2, 00185 Rome, Italy
| | - Marta Di Fabrizio
- Laboratory of Biological Electron Microscopy, School of Basic Sciences, Institute of Physics, EPFL & Department of Fundamental Microbiology, Faculty of Biology and Medicine, UNIL, 1015 Lausanne, Switzerland
| | - Tiziana Mancini
- Department of Physics, University of Rome 'La Sapienza', P.le A. Moro 2, 00185 Rome, Italy
| | - Rosanna Mosetti
- Department of Physics, University of Rome 'La Sapienza', P.le A. Moro 2, 00185 Rome, Italy
| | - Salvatore Macis
- Department of Physics, University of Rome 'La Sapienza', P.le A. Moro 2, 00185 Rome, Italy
| | - Giovanna Tranfo
- Department of Occupational and Environmental Medicine, Epidemiology and Hygiene, INAIL, Monte Porzio Catone, 00078 Rome, Italy
| | - Giancarlo Della Ventura
- Laboratori Nazionali Frascati, National Institute for Nuclear Physics (INFN-LNF), Via E. Fermi 54, 00044 Frascati, Italy
- Department of Science, University Rome Tre, Largo San Leonardo Murialdo 1, 00146 Rome, Italy
| | - Augusto Marcelli
- Laboratori Nazionali Frascati, National Institute for Nuclear Physics (INFN-LNF), Via E. Fermi 54, 00044 Frascati, Italy
- Rome International Centre for Materials Science Superstipes, Via dei Sabelli 119A, 00185 Rome, Italy
| | - Massimo Petrarca
- National Institute for Nuclear Physics Section Rome1, P.le A. Moro 2, 00185 Rome, Italy
- Department of Basic and Applied Sciences for Engineering (SBAI), University of Rome 'La Sapienza', Via Scarpa 16, 00161 Rome, Italy
| | - Stefano Lupi
- Department of Physics, University of Rome 'La Sapienza', P.le A. Moro 2, 00185 Rome, Italy
- National Institute for Nuclear Physics Section Rome1, P.le A. Moro 2, 00185 Rome, Italy
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Fardelli E, D'Arco A, Lupi S, Billi D, Moeller R, Guidi MC. Spectroscopic evidence of the radioresistance of Chroococcidiopsis biosignatures: A combined Raman, FT-IR and THz-TDs spectroscopy study. SPECTROCHIMICA ACTA. PART A, MOLECULAR AND BIOMOLECULAR SPECTROSCOPY 2023; 288:122148. [PMID: 36462318 DOI: 10.1016/j.saa.2022.122148] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/12/2022] [Revised: 10/07/2022] [Accepted: 10/11/2022] [Indexed: 06/17/2023]
Abstract
In the last decades, Mars has been widely studied with on-site missions and observations, showing a planet that could have hosted life in the past. For this reason, the recent and future space missions on the red planet will search for traces of past and, possibly, present life. As a basis for these missions, Space Agencies, such as the European Space Agency, have conducted many experiments on living organisms, studying their behavior in extraterrestrial conditions, learning to recognize their biosignatures with techniques remotely controllable such as Raman spectroscopy. Among these organisms, the radioresistant cyanobacterium Chroococcidiopsis was irradiated during the STARLIFE campaign with strong radiative insults. In this article we have investigated this cyanobacterium using Raman spectroscopy and extended the characterization of its biosignatures and its response to the radiative stress to the mid- Infrared and Terahertz spectral region using the Fourier Transform InfraRed (FT-IR) and Terahertz Time Domain spectroscopy (THz- TDs), which demonstrates the compatibility and suitability of these techniques for future space missions.
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Affiliation(s)
- Elisa Fardelli
- University of Roma Tre, Department of Science, Viale G. Marconi, 446, Rome, 00146, Italy.
| | - Annalisa D'Arco
- University of La Sapienza, Department of Physics, P.le A. Moro, 5, Rome, 00185, Italy
| | - Stefano Lupi
- University of La Sapienza, Department of Physics, P.le A. Moro, 5, Rome, 00185, Italy; INFN - LNF, Via E. Fermi, 54, Frascati, 00044, Italy
| | - Daniela Billi
- University of Tor Vergata, Department of Biology, Via della ricerca scientifica, 1, Rome, 00133, Italy
| | - Ralf Moeller
- Institute of Aerospace Medicine, section Aerospace Microbiology, Linder Hohe, Cologne, 51147, Germany
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D'Arco A, Rocco D, Piamonte Magboo F, Moffa C, Della Ventura G, Marcelli A, Palumbo L, Mattiello L, Lupi S, Petrarca M. Terahertz continuous wave spectroscopy: a portable advanced method for atmospheric gas sensing. OPTICS EXPRESS 2022; 30:19005-19016. [PMID: 36221688 DOI: 10.1364/oe.456022] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/11/2022] [Accepted: 04/05/2022] [Indexed: 06/16/2023]
Abstract
Motivated by the increasing demand to monitor the air-quality, our study proved the feasibility of a new compact and portable experimental approach based on Terahertz (THz) continuous wave high resolution spectroscopy, to detect the presence of the air's contaminants as greenhouse gases (GHG) and volatile organic compounds (VOCs). In this specific work, we first characterized, determining their molar absorption coefficient in the spectral region (0.06-1.2) THz, the pure optical response of the vapor of five VOCs: methanol, ethanol, isopropanol, 1-butanol and 2-butanol. In particular, 1-butanol and 2-butanol are characterized for the first time in literature at THz frequencies. Then we studied the optical response of their mixtures achieved with ambient air and ethanol. The results show that it is possible for a differentiation of single components by describing their spectral absorption in terms of the linear combination of pure compounds absorption. This proof of concept for this apparatus study and set-up paves the way to the use of THz Continuous wave high resolution spectroscopy for the environmental tracking of air pollutants.
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Abstract
Proteins play a key role in living organisms. The study of proteins and their dynamics provides information about their functionality, catalysis and potential alterations towards pathological diseases. Several techniques are used for studying protein dynamics, e.g., magnetic resonance, fluorescence imaging techniques, mid-infrared spectroscopy and biochemical assays. Spectroscopic analysis, based on the use of terahertz (THz) radiation with frequencies between 0.1 and 15 THz (3–500 cm−1), was underestimated by the biochemical community. In recent years, however, the potential of THz spectroscopy in the analysis of both simple structures, such as polypeptide molecules, and complex structures, such as protein complexes, has been demonstrated. The THz absorption spectrum provides some information on proteins: for small molecules the THz spectrum is dominated by individual modes related to the presence of hydrogen bonds. For peptides, the spectral information concerns their secondary structure, while for complex proteins such as globular proteins and viral glycoproteins, spectra also provide information on collective modes. In this short review, we discuss the results obtained by THz spectroscopy in the protein dynamics investigations. In particular, we will illustrate advantages and applications of THz spectroscopy, pointing out the complementary information it may provide.
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Wang H, Xie Q, Xu XG. Super-resolution mid-infrared spectro-microscopy of biological applications through tapping mode and peak force tapping mode atomic force microscope. Adv Drug Deliv Rev 2022; 180:114080. [PMID: 34906646 DOI: 10.1016/j.addr.2021.114080] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2021] [Revised: 11/15/2021] [Accepted: 12/06/2021] [Indexed: 11/19/2022]
Abstract
Small biomolecules at the subcellular level are building blocks for the manifestation of complex biological activities. However, non-intrusive in situ investigation of biological systems has been long daunted by the low spatial resolution and poor sensitivity of conventional light microscopies. Traditional infrared (IR) spectro-microscopy can enable label-free visualization of chemical bonds without extrinsic labeling but is still bound by Abbe's diffraction limit. This review article introduces a way to bypass the optical diffraction limit and improve the sensitivity for mid-IR methods - using tip-enhanced light nearfield in atomic force microscopy (AFM) operated in tapping and peak force tapping modes. Working principles of well-established scattering-type scanning near-field optical microscopy (s-SNOM) and two relatively new techniques, namely, photo-induced force microscopy (PiFM) and peak force infrared (PFIR) microscopy, will be briefly presented. With ∼ 10-20 nm spatial resolution and monolayer sensitivity, their recent applications in revealing nanoscale chemical heterogeneities in a wide range of biological systems, including biomolecules, cells, tissues, and biomaterials, will be reviewed and discussed. We also envision several future improvements of AFM-based tapping and peak force tapping mode nano-IR methods that permit them to better serve as a versatile platform for uncovering biological mechanisms at the fundamental level.
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Affiliation(s)
- Haomin Wang
- Division of Chemistry and Chemical Engineering, California Institute of Technology, Pasadena, CA 91125, USA
| | - Qing Xie
- Department of Chemistry, Lehigh University, Bethlehem, PA 18015, USA
| | - Xiaoji G Xu
- Department of Chemistry, Lehigh University, Bethlehem, PA 18015, USA.
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Attenuated Total Reflection at THz Wavelengths: Prospective Use of Total Internal Reflection and Polariscopy. APPLIED SCIENCES-BASEL 2021. [DOI: 10.3390/app11167632] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
Capabilities of the attenuated total reflection (ATR) at THz wavelengths for increased sub-surface depth characterisation of (bio-)materials are presented. The penetration depth of a THz evanescent wave in biological samples is dependent on the wavelength and temperature and can reach 0.1–0.5 mm depth, due to the strong refractive index change ∼0.4 of the ice-water transition; this is quite significant and important when studying biological samples. Technical challenges are discussed when using ATR for uneven, heterogeneous, high refractive index samples with the possibility of frustrated total internal reflection (a breakdown of the ATR reflection mode into transmission mode). Local field enhancements at the interface are discussed with numerical/analytical examples. Maxwell’s scaling is used to model the behaviour of absorber–scatterer inside the materials at the interface with the ATR prism for realistic complex refractive indices of bio-materials. The modality of ATR with a polarisation analysis is proposed, and its principle is illustrated, opening an invitation for its experimental validation. The sensitivity of the polarised ATR mode to the refractive index between the sample and ATR prism is numerically modelled and experimentally verified for background (air) spectra. The design principles of polarisation active optical elements and spectral filters are outlined. The results and proposed concepts are based on experimental conditions at the THz beamline of the Australian Synchrotron.
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