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Zeng P, Zhou Y, Shu Z, Liang H, Zhang X, Chen Y, Duan H, Zheng M. Suspended 3D metallic dimers with sub-10 nm gap for high-sensitive SERS detection. NANOTECHNOLOGY 2022; 34:095301. [PMID: 36384034 DOI: 10.1088/1361-6528/aca338] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/21/2022] [Accepted: 11/14/2022] [Indexed: 06/16/2023]
Abstract
The suspended metallic nanostructures with tiny gaps have certain advantages in surface-enhanced Raman scattering (SERS) due to the coaction of the tiny metallic nanogaps and the substrate-decoupled electromagnetism resonant modes. In this study, we used the lithographic HSQ/PMMA electron-beam bilayer resist exposure combined with a deposition-induced nanogap-narrowing process to define elevated suspended metallic nanodimers with tiny gaps for surface-enhanced Raman spectroscopy detection. By adjusting the deposited metal thickness, the metallic dimers with sub-10 nm gaps can be reliably obtained. These dimers with tunable nanogaps successfully served as excellent SERS substrates, exhibiting remarkable high-sensitivity detection ability for crystal violet molecules. Systematic experiments and simulations were conducted to explain the origin of the improved SERS performance. The results showed that the 3D elevated suspended metallic dimers could achieve a higher SERS enhancement factor than the metallic dimers on HSQ pillars and a common Si substrate, demonstrating that this kind of suspended metallic dimer is a promising route for high-sensitive SERS detection and other plasmonic applications.
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Affiliation(s)
- Pei Zeng
- Jihua Laboratory, Foshan 528000, People's Republic of China
- College of Mechanical and Vehicle Engineering, National Engineering Research Centre for High Efficiency Grinding, Hunan University, Changsha 410082, People's Republic of China
| | - Yuting Zhou
- College of Mechanical and Vehicle Engineering, National Engineering Research Centre for High Efficiency Grinding, Hunan University, Changsha 410082, People's Republic of China
| | - Zhiwen Shu
- College of Mechanical and Vehicle Engineering, National Engineering Research Centre for High Efficiency Grinding, Hunan University, Changsha 410082, People's Republic of China
| | - Huikang Liang
- College of Mechanical and Vehicle Engineering, National Engineering Research Centre for High Efficiency Grinding, Hunan University, Changsha 410082, People's Republic of China
| | - Xiaoqing Zhang
- College of Mechanical and Vehicle Engineering, National Engineering Research Centre for High Efficiency Grinding, Hunan University, Changsha 410082, People's Republic of China
| | - Yiqin Chen
- College of Mechanical and Vehicle Engineering, National Engineering Research Centre for High Efficiency Grinding, Hunan University, Changsha 410082, People's Republic of China
| | - Huigao Duan
- College of Mechanical and Vehicle Engineering, National Engineering Research Centre for High Efficiency Grinding, Hunan University, Changsha 410082, People's Republic of China
| | - Mengjie Zheng
- Jihua Laboratory, Foshan 528000, People's Republic of China
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2
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Ko RHH, Shayegannia M, Farid S, Kherani NP. Protein capture and SERS detection on multiwavelength rainbow-trapping width-graded nano-gratings. NANOTECHNOLOGY 2021; 32:505207. [PMID: 34544057 DOI: 10.1088/1361-6528/ac2842] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/10/2021] [Accepted: 09/20/2021] [Indexed: 06/13/2023]
Abstract
Surface-enhanced Raman scattering (SERS) substrates with multiwavelength rainbow-trapping properties hold the potential for a one-size-fits-all platform for rapid and multiplexed disease detection. We present the first report on the utilization of rainbow-trapping width-graded nano-gratings, a new class of chirped metamaterials, to detect protein biomarkers. Using cytochrome c (Cc), a charged analyte with inherent difficulty in adsorbing onto sputtered silver films, we investigated methods of binding Cc on the silver nano-grating in order to improve the SERS signal strength at both 532 and 638 nm excitation. Cc was not detectable on the Ag nano-gratings without surface functionalization at 1μM concentration. Upon charge reversal functionalization of the Ag nano-gratings, 1μM Cc was detectable albeit not reliably. By further crosslinking 1μM Cc to the functionalized Ag nano-gratings, the analyte-capture detection scheme greatly improved the SERS signal strength and reliability at both excitation wavelengths and allowed for quantification of their coefficients of variation with values down to 27%.
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Affiliation(s)
- Remy H H Ko
- Department of Electrical & Computer Engineering, University of Toronto, Toronto, ON Canada M5S 3G4, Canada
| | - Moein Shayegannia
- Department of Electrical & Computer Engineering, University of Toronto, Toronto, ON Canada M5S 3G4, Canada
| | - Sidra Farid
- Department of Electrical & Computer Engineering, University of Toronto, Toronto, ON Canada M5S 3G4, Canada
| | - Nazir P Kherani
- Department of Electrical & Computer Engineering, University of Toronto, Toronto, ON Canada M5S 3G4, Canada
- Department of Materials Science & Engineering, University of Toronto, Toronto, ON Canada M5S 3E4, Canada
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3
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Dai C, Lin Z, Agarwal K, Mikhael C, Aich A, Gupta K, Cho JH. Self-Assembled 3D Nanosplit Rings for Plasmon-Enhanced Optofluidic Sensing. NANO LETTERS 2020; 20:6697-6705. [PMID: 32808792 DOI: 10.1021/acs.nanolett.0c02575] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
Plasmonic sensors are commonly defined on two-dimensional (2D) surfaces with an enhanced electromagnetic field only near the surface, which requires precise positioning of the targeted molecules within hotspots. To address this challenge, we realize segmented nanocylinders that incorporate plasmonic (1-50 nm) gaps within three-dimensional (3D) nanostructures (nanocylinders) using electron irradiation triggered self-assembly. The 3D structures allow desired plasmonic patterns on their inner cylindrical walls forming the nanofluidic channels. The nanocylinders bridge nanoplasmonics and nanofluidics by achieving electromagnetic field enhancement and fluid confinement simultaneously. This hybrid system enables rapid diffusion of targeted species to the larger spatial hotspots in the 3D plasmonic structures, leading to enhanced interactions that contribute to a higher sensitivity. This concept has been demonstrated by characterizing an optical response of the 3D plasmonic nanostructures using surface-enhanced Raman spectroscopy (SERS), which shows enhancement over a 22 times higher intensity for hemoglobin fingerprints with nanocylinders compared to 2D nanostructures.
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Affiliation(s)
- Chunhui Dai
- Department of Electrical and Computer Engineering, University of Minnesota, Minneapolis, Minnesota 55455, United States
| | - Zihao Lin
- Department of Electrical and Computer Engineering, University of Minnesota, Minneapolis, Minnesota 55455, United States
| | - Kriti Agarwal
- Department of Electrical and Computer Engineering, University of Minnesota, Minneapolis, Minnesota 55455, United States
| | - Carol Mikhael
- Department of Electrical and Computer Engineering, University of Minnesota, Minneapolis, Minnesota 55455, United States
| | - Anupam Aich
- Hematology/Oncology Division, Department of Medicine, University of California, Irvine, California 92697, United States
| | - Kalpna Gupta
- Hematology/Oncology Division, Department of Medicine, University of California, Irvine, California 92697, United States
- Division of Hematology, Oncology and Transplantation, University of Minnesota, Minneapolis, Minnesota 55455, United States
- SCIRE, Veterans Affairs Medical Center, Long Beach, California 90822, United States
| | - Jeong-Hyun Cho
- Department of Electrical and Computer Engineering, University of Minnesota, Minneapolis, Minnesota 55455, United States
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Milewska A, Zivanovic V, Merk V, Arnalds UB, Sigurjónsson ÓE, Kneipp J, Leosson K. Gold nanoisland substrates for SERS characterization of cultured cells. BIOMEDICAL OPTICS EXPRESS 2019; 10:6172-6188. [PMID: 31853393 PMCID: PMC6913407 DOI: 10.1364/boe.10.006172] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/20/2019] [Revised: 11/01/2019] [Accepted: 11/03/2019] [Indexed: 05/17/2023]
Abstract
We demonstrate a simple approach for fabricating cell-compatible SERS substrates, using repeated gold deposition and thermal annealing. The substrates exhibit SERS enhancement up to six orders of magnitude and high uniformity. We have carried out Raman imaging of fixed mesenchymal stromal cells cultured directly on the substrates. Results of viability assays confirm that the substrates are highly biocompatible and Raman imaging confirms that cell attachment to the substrates is sufficient to realize significant SERS enhancement of cellular components. Using the SERS substrates as an in vitro sensing platform allowed us to identify multiple characteristic molecular fingerprints of the cells, providing a promising avenue towards non-invasive chemical characterization of biological samples.
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Affiliation(s)
- Adrianna Milewska
- Innovation Center Iceland, Árleynir 2–8, 112 Reykjavík, Iceland
- The Blood Bank, Landspitali University Hospital, Snorrabraut 60, 105 Reykjavík, Iceland
- University of Iceland, School of Engineering and Natural Sciences, Sæmundargötu 2, 101 Reykjavík, Iceland
| | - Vesna Zivanovic
- Humboldt University, Brook-Taylor-Str. 2, 12489, Berlin, Germany
| | - Virginia Merk
- Humboldt University, Brook-Taylor-Str. 2, 12489, Berlin, Germany
| | - Unnar B. Arnalds
- Science Institute, University of Iceland, Dunhaga 3, 107 Reykjavík, Iceland
| | - Ólafur E. Sigurjónsson
- The Blood Bank, Landspitali University Hospital, Snorrabraut 60, 105 Reykjavík, Iceland
- Reykjavik University, School of Science and Engineering, Menntavegur 1, 101 Reykjavík, Iceland
| | - Janina Kneipp
- Humboldt University, Brook-Taylor-Str. 2, 12489, Berlin, Germany
| | - Kristjan Leosson
- Innovation Center Iceland, Árleynir 2–8, 112 Reykjavík, Iceland
- Science Institute, University of Iceland, Dunhaga 3, 107 Reykjavík, Iceland
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5
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Díaz-Núñez P, García-Martín JM, González MU, González-Arrabal R, Rivera A, Alonso-González P, Martín-Sánchez J, Taboada-Gutiérrez J, González-Rubio G, Guerrero-Martínez A, Bañares L, Peña-Rodríguez O. On the Large Near-Field Enhancement on Nanocolumnar Gold Substrates. Sci Rep 2019; 9:13933. [PMID: 31558753 PMCID: PMC6763449 DOI: 10.1038/s41598-019-50392-w] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2019] [Accepted: 07/31/2019] [Indexed: 11/08/2022] Open
Abstract
One of the most important and distinctive features of plasmonic nanostructures is their ability to confine large electromagnetic fields on nanometric volumes; i.e., the so-called hot spots. The generation, control and characterization of the hot spots are fundamental for several applications, like surface-enhanced spectroscopies. In this work, we characterize the near-field distribution and enhancement of nanostructured gold thin films fabricated by glancing angle deposition magnetron sputtering. These films are composed of columnar nanostructures with high roughness and high density of inter-columnar gaps, where the electromagnetic radiation can be confined, generating hot spots. As expected, the hot spots are localized in the gaps between adjacent nanocolumns and we use scattering-type scanning near-field optical microscopy to image their distribution over the surface of the samples. The experimental results are compared with finite-difference time-domain simulations, finding an excellent agreement between them. The spectral dependence of the field-enhancement is also studied with the simulations, together with surface-enhanced Raman spectroscopy at different excitation wavelengths in the visible-NIR range, proving a broad-band response of the substrates. These findings may result in interesting applications in the field of surface-enhanced optical spectroscopies or sensing.
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Affiliation(s)
- Pablo Díaz-Núñez
- Instituto de Fusión Nuclear "Guillermo Velarde", Universidad Politécnica de Madrid, José Gutiérrez Abascal 2, E-28006, Madrid, Spain.
| | - José Miguel García-Martín
- Instituto de Micro y Nanotecnología, IMN-CNM, CSIC (CEI UAM+CSIC), Isaac Newton 8, 28760, Tres Cantos, Spain
| | - María Ujué González
- Instituto de Micro y Nanotecnología, IMN-CNM, CSIC (CEI UAM+CSIC), Isaac Newton 8, 28760, Tres Cantos, Spain
| | - Raquel González-Arrabal
- Instituto de Fusión Nuclear "Guillermo Velarde", Universidad Politécnica de Madrid, José Gutiérrez Abascal 2, E-28006, Madrid, Spain
- Departamento de Ingeniería Energética, Escuela Técnica Superior de Ingenieros Industriales, Universidad Politécnica de Madrid, José Gutiérrez Abascal 2, E-28006, Madrid, Spain
| | - Antonio Rivera
- Instituto de Fusión Nuclear "Guillermo Velarde", Universidad Politécnica de Madrid, José Gutiérrez Abascal 2, E-28006, Madrid, Spain
- Departamento de Ingeniería Energética, Escuela Técnica Superior de Ingenieros Industriales, Universidad Politécnica de Madrid, José Gutiérrez Abascal 2, E-28006, Madrid, Spain
| | - Pablo Alonso-González
- Departamento de Física, Universidad de Oviedo, E-33007, Oviedo, Spain
- Center of Research on Nanomaterials and Nanotechnology, CINN (CSIC-Universidad de Oviedo), El Entrego, 33940, Spain
| | - Javier Martín-Sánchez
- Departamento de Física, Universidad de Oviedo, E-33007, Oviedo, Spain
- Center of Research on Nanomaterials and Nanotechnology, CINN (CSIC-Universidad de Oviedo), El Entrego, 33940, Spain
| | - Javier Taboada-Gutiérrez
- Departamento de Física, Universidad de Oviedo, E-33007, Oviedo, Spain
- Center of Research on Nanomaterials and Nanotechnology, CINN (CSIC-Universidad de Oviedo), El Entrego, 33940, Spain
| | - Guillermo González-Rubio
- Departamento de Química Física, Universidad Complutense de Madrid, Avenida Complutense s/n, E-28040, Madrid, Spain
- Bionanoplasmonics Laboratory, CIC biomaGUNE, Paseo de Miramón 182, 20014, Donostia, San Sebastián, Spain
| | - Andrés Guerrero-Martínez
- Departamento de Química Física, Universidad Complutense de Madrid, Avenida Complutense s/n, E-28040, Madrid, Spain
| | - Luis Bañares
- Departamento de Química Física, Universidad Complutense de Madrid, Avenida Complutense s/n, E-28040, Madrid, Spain
- Centro de Láseres Ultrarrápidos, Universidad Complutense de Madrid, Avenida Complutense s/n, E-28040, Madrid, Spain
| | - Ovidio Peña-Rodríguez
- Instituto de Fusión Nuclear "Guillermo Velarde", Universidad Politécnica de Madrid, José Gutiérrez Abascal 2, E-28006, Madrid, Spain
- Departamento de Ingeniería Energética, Escuela Técnica Superior de Ingenieros Industriales, Universidad Politécnica de Madrid, José Gutiérrez Abascal 2, E-28006, Madrid, Spain
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6
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Jubb AM, Eskelsen JR, Yin X, Zheng J, Philben MJ, Pierce EM, Graham DE, Wullschleger SD, Gu B. Characterization of iron oxide nanoparticle films at the air-water interface in Arctic tundra waters. THE SCIENCE OF THE TOTAL ENVIRONMENT 2018; 633:1460-1468. [PMID: 29758898 DOI: 10.1016/j.scitotenv.2018.03.332] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/14/2018] [Revised: 03/26/2018] [Accepted: 03/27/2018] [Indexed: 06/08/2023]
Abstract
Massive amounts of organic carbon have accumulated in Arctic permafrost and soils due to anoxic and low temperature conditions that limit aerobic microbial respiration. Alternative electron acceptors are thus required for microbes to degrade organic carbon in these soils. Iron or iron oxides have been recognized to play an important role in carbon cycle processes in Arctic soils, although the exact form and role as an electron acceptor or donor remain poorly understood. Here, Arctic biofilms collected during the summers of 2016 and 2017 from tundra surface waters on the Seward Peninsula of western Alaska were characterized with a suite of microscopic and spectroscopic methods. We hypothesized that these films contain redox-active minerals bound to biological polymers. The major components of the films were found to be iron oxide nanoparticle aggregates associated with extracellular polymeric substances. The observed mineral phases varied between films collected in different years with magnetite (Fe2+Fe23+O4) nanoparticles (<5nm) predominantly identified in the 2016 films, while for films collected in 2017 ferrihydrite-like amorphous iron oxyhydroxides were found. While the exact formation mechanism of these Artic iron oxide films remains to be explored, the presence of magnetite and other iron oxide/oxyhydroxide nanoparticles at the air-water interface may represent a previously unknown source of electron acceptors for continual anaerobic microbial respiration of organic carbon within poorly drained Arctic tundra.
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Affiliation(s)
- Aaron M Jubb
- Environmental Sciences Division, Oak Ridge National Laboratory, Oak Ridge, TN, USA.
| | - Jeremy R Eskelsen
- Environmental Sciences Division, Oak Ridge National Laboratory, Oak Ridge, TN, USA
| | - Xiangping Yin
- Environmental Sciences Division, Oak Ridge National Laboratory, Oak Ridge, TN, USA
| | - Jianqiu Zheng
- Biosciences Division, Oak Ridge National Laboratory, Oak Ridge, TN, USA
| | - Michael J Philben
- Environmental Sciences Division, Oak Ridge National Laboratory, Oak Ridge, TN, USA
| | - Eric M Pierce
- Environmental Sciences Division, Oak Ridge National Laboratory, Oak Ridge, TN, USA
| | - David E Graham
- Biosciences Division, Oak Ridge National Laboratory, Oak Ridge, TN, USA; Climate Change Science Institute, Oak Ridge National Laboratory, Oak Ridge, TN, USA
| | - Stan D Wullschleger
- Environmental Sciences Division, Oak Ridge National Laboratory, Oak Ridge, TN, USA; Climate Change Science Institute, Oak Ridge National Laboratory, Oak Ridge, TN, USA
| | - Baohua Gu
- Environmental Sciences Division, Oak Ridge National Laboratory, Oak Ridge, TN, USA; Department of Biosystems Engineering and Soil Science, University of Tennessee, Knoxville, TN, USA.
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7
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Timmermans FJ, Lenferink ATM, van Wolferen HAGM, Otto C. Correlative SEM SERS for quantitative analysis of dimer nanoparticles. Analyst 2018; 141:6455-6462. [PMID: 27796389 DOI: 10.1039/c6an01648k] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
A Raman microscope integrated with a scanning electron microscope was used to investigate plasmonic structures by correlative SEM-SERS analysis. The integrated Raman-SEM microscope combines high-resolution electron microscopy information with SERS signal enhancement from selected nanostructures with adsorbed Raman reporter molecules. Correlative analysis is performed for dimers of two gold nanospheres. Dimers were selected on the basis of SEM images from multi aggregate samples. The effect of the orientation of the dimer with respect to the polarization state of the laser light and the effect of the particle gap size on the Raman signal intensity is observed. Additionally, calculations are performed to simulate the electric near field enhancement. These simulations are based on the morphologies observed by electron microscopy. In this way the experiments are compared with the enhancement factor calculated with near field simulations and are subsequently used to quantify the SERS enhancement factor. Large differences between experimentally observed and calculated enhancement factors are regularly detected, a phenomenon caused by nanoscale differences between the real and 'simplified' simulated structures. Quantitative SERS experiments reveal the structure induced enhancement factor, ranging from ∼200 to ∼20 000, averaged over the full nanostructure surface. The results demonstrate correlative Raman-SEM microscopy for the quantitative analysis of plasmonic particles and structures, thus enabling a new analytical method in the field of SERS and plasmonics.
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Affiliation(s)
- F J Timmermans
- Medical Cell BioPhysics Group, MIRA Institute, University of Twente, PO Box 217, 7500 AE Enschede, The Netherlands.
| | - A T M Lenferink
- Medical Cell BioPhysics Group, MIRA Institute, University of Twente, PO Box 217, 7500 AE Enschede, The Netherlands.
| | - H A G M van Wolferen
- Transducers Science and Technology, MESA+ Institute, University of Twente, The Netherlands
| | - C Otto
- Medical Cell BioPhysics Group, MIRA Institute, University of Twente, PO Box 217, 7500 AE Enschede, The Netherlands.
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8
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Huo D, Ding H, Zhou S, Li J, Tao J, Ma Y, Xia Y. Facile synthesis of gold trisoctahedral nanocrystals with controllable sizes and dihedral angles. NANOSCALE 2018; 10:11034-11042. [PMID: 29872819 DOI: 10.1039/c8nr02949k] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
Shape-controlled synthesis of Au nanocrystals is of paramount importance to their applications in plasmonics, catalysis, and nanomedicine. While the synthesis of Au nanocrystals enclosed by low-index facets has been greatly advanced over the past two decades, only limited progress has been made for their high-index counterparts. Here we report a robust route to the facile synthesis of Au trisoctahedral nanocrystals enclosed by high-index facets. Unlike the previously reported methods, our synthesis was conducted at room temperature, together with the introduction a new Au(iii) precursor that was much harder to reduce than AuCl4-. In the setting of seed-mediated growth, the trisoctahedral nanocrystals could be readily prepared with sizes controllable from 20-80 nm and dihedral angles tunable in the range of 120-180 degrees. We further used computational modeling to demonstrate that the surface-functionalized Au trisoctahedral nanocrystal could outperform its spherical counterpart in terms of endocytic efficacy under identical conditions.
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Affiliation(s)
- Da Huo
- The Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology and Emory University, Atlanta, Georgia 30332, USA.
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9
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Alrasheed S, Di Fabrizio E. Effect of Surface Plasmon Coupling to Optical Cavity Modes on the Field Enhancement and Spectral Response of Dimer-Based sensors. Sci Rep 2017; 7:10524. [PMID: 28874769 PMCID: PMC5585175 DOI: 10.1038/s41598-017-11140-0] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2017] [Accepted: 08/18/2017] [Indexed: 11/08/2022] Open
Abstract
We present a theoretical approach to narrow the plasmon linewidth and enhance the near-field intensity at a plasmonic dimer gap (hot spot) through coupling the electric localized surface plasmon (LSP) resonance of a silver hemispherical dimer with the resonant modes of a Fabry-Perot (FP) cavity. The strong coupling is demonstrated by the large anticrossing in the reflection spectra and a Rabi splitting of 76 meV. Up to 2-fold enhancement increase can be achieved compared to that without using the cavity. Such high field enhancement has potential applications in optics, including sensors and high resolution imaging devices. In addition, the resonance splitting allows for greater flexibility in using the same array at different wavelengths. We then further propose a practical design to realize such a device and include dimers of different shapes and materials.
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Affiliation(s)
- Salma Alrasheed
- King Abdullah University of Science and Technology, PSE and BESE Divisions, Thuwal, 23955-6900, Saudi Arabia.
| | - Enzo Di Fabrizio
- King Abdullah University of Science and Technology, PSE and BESE Divisions, Thuwal, 23955-6900, Saudi Arabia
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10
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Wei L, Sheng T, Ye JY, Lu BA, Tian N, Zhou ZY, Zhao XS, Sun SG. Seeds and Potentials Mediated Synthesis of High-Index Faceted Gold Nanocrystals with Enhanced Electrocatalytic Activities. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2017; 33:6991-6998. [PMID: 28657756 DOI: 10.1021/acs.langmuir.7b00964] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
Because high-index facets (HIFs) possess high surface energy, the metal nanoparticles enclosed with HIFs are eliminated during their growth in a conventional shape-controlled synthesis due to the thermodynamics that drives the particles minimizing their total surface energy. This study develops a double-step potential method to prepare an unprecedentedly stellated Au nanocrystals (NCs) bounded by high-index {711} and {331} facets in deep eutectic solvent (DES) medium. The formation of Au NCs bounded by HIFs was systematically studied. It has demonstrated that the shapes of Au NCs are strongly dependent on the size of seeds and the growth potentials as well as the urea adsorbates in the DES. By adjusting the size of seeds and the growth potentials, the stellated Au NCs can be transformed into concave hexoctahedra (HOH) with high-index {421} facets and concave trisoctahedra (TOH) with high-index {991} facets. The electrocatalytic activities of the as-prepared Au NCs are evaluated by glucose oxidation. Thanks to HIFs having high density of atomic steps and kinks, the stellated, TOH, and HOH Au NCs exhibit higher electrocatalytic activity than that of the polycrystalline Au electrode, demonstrating that the steps and kinks serve as the active sites and play an important role in glucose electro-oxidation.
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Affiliation(s)
- Lu Wei
- Department of Physics, School of Physics and Electronic Engineering, Jiangsu Normal University , Xuzhou 221116, China
- State Key Lab of PCOSS, College of Chemistry and Chemical Engineering, Xiamen University , Xiamen 361005, China
| | - Tian Sheng
- State Key Lab of PCOSS, College of Chemistry and Chemical Engineering, Xiamen University , Xiamen 361005, China
| | - Jin-Yu Ye
- State Key Lab of PCOSS, College of Chemistry and Chemical Engineering, Xiamen University , Xiamen 361005, China
| | - Bang-An Lu
- State Key Lab of PCOSS, College of Chemistry and Chemical Engineering, Xiamen University , Xiamen 361005, China
| | - Na Tian
- State Key Lab of PCOSS, College of Chemistry and Chemical Engineering, Xiamen University , Xiamen 361005, China
| | - Zhi-You Zhou
- State Key Lab of PCOSS, College of Chemistry and Chemical Engineering, Xiamen University , Xiamen 361005, China
| | - Xin-Sheng Zhao
- Department of Physics, School of Physics and Electronic Engineering, Jiangsu Normal University , Xuzhou 221116, China
| | - Shi-Gang Sun
- State Key Lab of PCOSS, College of Chemistry and Chemical Engineering, Xiamen University , Xiamen 361005, China
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11
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Review of SERS Substrates for Chemical Sensing. NANOMATERIALS 2017; 7:nano7060142. [PMID: 28594385 PMCID: PMC5485789 DOI: 10.3390/nano7060142] [Citation(s) in RCA: 262] [Impact Index Per Article: 37.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/16/2017] [Revised: 06/02/2017] [Accepted: 06/06/2017] [Indexed: 12/21/2022]
Abstract
The SERS effect was initially discovered in the 1970s. Early research focused on understanding the phenomenon and increasing enhancement to achieve single molecule detection. From the mid-1980s to early 1990s, research started to move away from obtaining a fundamental understanding of the phenomenon to the exploration of analytical applications. At the same time, significant developments occurred in the field of photonics that led to the advent of inexpensive, robust, compact, field-deployable Raman systems. The 1990s also saw rapid development in nanoscience. This convergence of technologies (photonics and nanoscience) has led to accelerated development of SERS substrates to detect a wide range of chemical and biological analytes. It would be a monumental task to discuss all the different kinds of SERS substrates that have been explored. Likewise, it would be impossible to discuss the use of SERS for both chemical and biological detection. Instead, a review of the most common metallic (Ag, Cu, and Au) SERS substrates for chemical detection only is discussed, as well as SERS substrates that are commercially available. Other issues with SERS for chemical detection have been selectivity, reversibility, and reusability of the substrates. How these issues have been addressed is also discussed in this review.
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