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Abstract
Surface-enhanced Raman scattering (SERS), a powerful technique for trace molecular detection, depends on chemical and electromagnetic enhancements. While recent advances in instrumentation and substrate design have expanded the utility, reproducibility, and quantitative capabilities of SERS, some challenges persist. In this review, advances in quantitative SERS detection are discussed as they relate to intermolecular interactions, surface selection rules, and target molecule solubility and accessibility. After a brief introduction to Raman scattering and SERS, impacts of surface selection rules and enhancement mechanisms are discussed as they relate to the observation of activation and deactivation of normal Raman modes in SERS. Next, experimental conditions that can be used to tune molecular affinity to and density near SERS substrates are summarized and considered while tuning these parameters are conveyed. Finally, successful examples of quantitative SERS detection are discussed, and future opportunities are outlined. Expected final online publication date for the Annual Review of Physical Chemistry, Volume 73 is April 2022. Please see http://www.annualreviews.org/page/journal/pubdates for revised estimates.
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Affiliation(s)
- Ryan D Norton
- Department of Chemistry, University of Iowa, Iowa City, Iowa, USA;
| | - Hoa T Phan
- Department of Chemistry, University of Iowa, Iowa City, Iowa, USA;
| | | | - Amanda J Haes
- Department of Chemistry, University of Iowa, Iowa City, Iowa, USA;
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2
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Phan HT, Vinson C, Haes AJ. Gold Nanostar Spatial Distribution Impacts the Surface-Enhanced Raman Scattering Detection of Uranyl on Amidoximated Polymers. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2021; 37:4891-4899. [PMID: 33861606 PMCID: PMC8213173 DOI: 10.1021/acs.langmuir.1c00132] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
The plasmonic properties of carboxylated gold nanostars distributed on amidoximated polyacrylonitrile (AO PAN) electrospun polymer films scale with surface-enhanced Raman scattering (SERS) intensities for coordinated uranium(VI) oxide (uranyl) species. This two-step plasmonic sensor first isolates uranyl from solution using functionalized polymers; then carboxylated gold nanostars are subsequently deposited for SERS. Spatially resolved localized surface plasmon resonance (LSPR) and SERS facilitate correlated nanostar optical density and uranyl quantification. To reduce sampling bias, gold nanostars are deposited in an inverted drop-coating geometry and measurements are conducted inside resulting nanoparticle coffee rings that form on the polymer substrates. This approach naturally preserves the plasmonic properties of gold nanostars while reducing the deposition of nanoparticle aggregates in active sensing regions, thereby maximizing both the accuracy and the precision of SERS measurements. Several advances are made. First, second-derivative analysis of LSPR spectra facilitates the quantification of local nanostar density across large regions of the sensor substrate by reducing background variations caused by the polymeric and gold materials. Second, local nanostar densities ranging from 140 to 200 pM·cm are shown to result in uranyl signals that are independent of nanostar concentration. Third, the Gibbs free energy of uranyl adsorption to carboxylated nanostars is estimated at 8.4 ± 0.2 kcal/mol. Finally, a linear dynamic range from ∼0.3 to 3.4 μg U/mg polymer is demonstrated. Signals vary by 10% or less. As such, the uniformity of the plasmonic activity of distributed gold nanostars and the employment of spatially resolved spectroscopic measurements on the composite nanomaterial sensor interface facilitate the quantitative detection of uranyl while also reducing the dependence on user expertise and the selected sampling region. These important advances are critical for the development of a user-friendly SERS-based sensor for uranyl.
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Affiliation(s)
- Hoa T. Phan
- Department of Chemistry, University of Iowa, Iowa City, Iowa 52242 United States
| | - Claire Vinson
- Department of Chemistry, Smith College, Northampton, Massachusetts 01063 and Department of Chemistry, University of Iowa, Iowa City, Iowa 52242 United States
| | - Amanda J. Haes
- Department of Chemistry, University of Iowa, Iowa City, Iowa 52242, United States
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3
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Zhang D, You H, Zhang L, Fang J. Facile Surface Modification of Mesoporous Au Nanoparticles for Highly Sensitive SERS Detection. Anal Chem 2020; 92:15379-15387. [PMID: 33171039 DOI: 10.1021/acs.analchem.0c02781] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
The stability, dispersity, and surface chemical properties of colloidal nanoparticles are crucial for the reliable and desired chemical sensing in various applications. Here, we report an effective strategy to engineer the surface properties of mesoporous Au nanoparticles (meso-Au NPs) via PVP ligand modification, template removal, and surface purification. Monodispersed 3D meso-Au NPs with well-defined sizes and shapes were obtained using a general soft-enveloping strategy. During surface modification, the addition of PVP ligands and the concentration of HF solutions play key roles in the stability, shape, and size distributions of ordered Au networks. In order to obtain an improved sensing performance, the morphologies of meso-Au NPs were optimized with smaller mesopore size, and NaBH4 solution was used to efficiently remove the adsorbed PVP ligands. Due to the characteristics of high-density porosities and large surface area, the purified meso-Au NPs could be a kind of promising plasmonic-enhanced nanomaterial and provide abundant "hot spots." Combined with the enrichment effect using a slippery liquid-infused porous surface, the lowest detection limits of crystal violet molecule could be down to 0.1 pM, demonstrating an excellent SERS sensitivity. Moreover, a realistic illegal drug containing aspirin could be sensitively detected with a limit of 2.8 × 10-6 M, showing great potential for practical molecular sensing and applications.
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Affiliation(s)
- Dongjie Zhang
- Key Laboratory for Physical Electronics and Devices of the Ministry of Education, School of Electronic Science and Engineering, Faculty of Electronic and Information Engineering, Xi'an Jiaotong University, Xi'an, Shann xi 710049, China
| | - Hongjun You
- School of Science, Xi'an Jiaotong University, Xi'an, Shann xi 710049, China
| | - Lingling Zhang
- Key Laboratory for Physical Electronics and Devices of the Ministry of Education, School of Electronic Science and Engineering, Faculty of Electronic and Information Engineering, Xi'an Jiaotong University, Xi'an, Shann xi 710049, China
| | - Jixiang Fang
- Key Laboratory for Physical Electronics and Devices of the Ministry of Education, School of Electronic Science and Engineering, Faculty of Electronic and Information Engineering, Xi'an Jiaotong University, Xi'an, Shann xi 710049, China
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4
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Luan J, Seth A, Gupta R, Wang Z, Rathi P, Cao S, Gholami Derami H, Tang R, Xu B, Achilefu S, Morrissey JJ, Singamaneni S. Ultrabright fluorescent nanoscale labels for the femtomolar detection of analytes with standard bioassays. Nat Biomed Eng 2020; 4:518-530. [PMID: 32313101 PMCID: PMC7231648 DOI: 10.1038/s41551-020-0547-4] [Citation(s) in RCA: 87] [Impact Index Per Article: 21.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2019] [Accepted: 03/09/2020] [Indexed: 01/28/2023]
Abstract
The detection and quantification of low-abundance molecular biomarkers in biological samples is challenging. Here, we show that a plasmonic nanoscale construct serving as an ‘add-on’ label for a broad range of bioassays improves their signal-to-noise ratio and dynamic range without altering their workflow and read-out devices. The plasmonic construct consists of a bovine-serum-albumin scaffold with approximately 210 IRDye 800CW fluorophores (with fluorescence intensity approximately 6700-fold that of a single 800CW fluorophore), a polymer-coated gold nanorod acting as a plasmonic antenna, and biotin as a high-affinity biorecognition element. Its emission wavelength can be tuned over the visible and near-infrared spectral regions by modifying its size, shape and composition. It is compatible with multiplexed bead-based immunoassays (it improves the limit of detection by up to 4,750-fold in fluorescence-linked immunosorbent assays), immuno-microarrays, flow-cytometry and immunocytochemistry methods, and it shortens overall assay times and lowers sample volumes, as shown for the detection of a pro-inflammatory cytokine in mouse interstitial fluid and of urinary biomarkers in patient samples.
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Affiliation(s)
- Jingyi Luan
- Department of Mechanical Engineering and Materials Science, Institute of Materials Science and Engineering, Washington University in St. Louis, St Louis, MO, USA
| | - Anushree Seth
- Department of Mechanical Engineering and Materials Science, Institute of Materials Science and Engineering, Washington University in St. Louis, St Louis, MO, USA
| | - Rohit Gupta
- Department of Mechanical Engineering and Materials Science, Institute of Materials Science and Engineering, Washington University in St. Louis, St Louis, MO, USA
| | - Zheyu Wang
- Department of Mechanical Engineering and Materials Science, Institute of Materials Science and Engineering, Washington University in St. Louis, St Louis, MO, USA
| | - Priya Rathi
- Department of Mechanical Engineering and Materials Science, Institute of Materials Science and Engineering, Washington University in St. Louis, St Louis, MO, USA
| | - Sisi Cao
- Department of Mechanical Engineering and Materials Science, Institute of Materials Science and Engineering, Washington University in St. Louis, St Louis, MO, USA
| | - Hamed Gholami Derami
- Department of Mechanical Engineering and Materials Science, Institute of Materials Science and Engineering, Washington University in St. Louis, St Louis, MO, USA
| | - Rui Tang
- Department of Radiology, Washington University School of Medicine, St. Louis, MO, USA
| | - Baogang Xu
- Department of Radiology, Washington University School of Medicine, St. Louis, MO, USA
| | - Samuel Achilefu
- Department of Radiology, Washington University School of Medicine, St. Louis, MO, USA
| | - Jeremiah J Morrissey
- Department of Anesthesiology, Division of Clinical and Translational Research, Washington University in St. Louis, St. Louis, MO, USA.,Siteman Cancer Center, Washington University in St. Louis, St. Louis, MO, USA
| | - Srikanth Singamaneni
- Department of Mechanical Engineering and Materials Science, Institute of Materials Science and Engineering, Washington University in St. Louis, St Louis, MO, USA. .,Siteman Cancer Center, Washington University in St. Louis, St. Louis, MO, USA.
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5
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Compartmentalization of gold nanoparticle clusters in hollow silica spheres and their assembly induced by an external electric field. J Colloid Interface Sci 2020; 566:202-210. [DOI: 10.1016/j.jcis.2020.01.094] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2019] [Revised: 01/17/2020] [Accepted: 01/24/2020] [Indexed: 02/06/2023]
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Langer J, Jimenez de Aberasturi D, Aizpurua J, Alvarez-Puebla RA, Auguié B, Baumberg JJ, Bazan GC, Bell SEJ, Boisen A, Brolo AG, Choo J, Cialla-May D, Deckert V, Fabris L, Faulds K, García de Abajo FJ, Goodacre R, Graham D, Haes AJ, Haynes CL, Huck C, Itoh T, Käll M, Kneipp J, Kotov NA, Kuang H, Le Ru EC, Lee HK, Li JF, Ling XY, Maier SA, Mayerhöfer T, Moskovits M, Murakoshi K, Nam JM, Nie S, Ozaki Y, Pastoriza-Santos I, Perez-Juste J, Popp J, Pucci A, Reich S, Ren B, Schatz GC, Shegai T, Schlücker S, Tay LL, Thomas KG, Tian ZQ, Van Duyne RP, Vo-Dinh T, Wang Y, Willets KA, Xu C, Xu H, Xu Y, Yamamoto YS, Zhao B, Liz-Marzán LM. Present and Future of Surface-Enhanced Raman Scattering. ACS NANO 2020; 14:28-117. [PMID: 31478375 PMCID: PMC6990571 DOI: 10.1021/acsnano.9b04224] [Citation(s) in RCA: 1347] [Impact Index Per Article: 336.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/08/2019] [Accepted: 09/03/2019] [Indexed: 04/14/2023]
Abstract
The discovery of the enhancement of Raman scattering by molecules adsorbed on nanostructured metal surfaces is a landmark in the history of spectroscopic and analytical techniques. Significant experimental and theoretical effort has been directed toward understanding the surface-enhanced Raman scattering (SERS) effect and demonstrating its potential in various types of ultrasensitive sensing applications in a wide variety of fields. In the 45 years since its discovery, SERS has blossomed into a rich area of research and technology, but additional efforts are still needed before it can be routinely used analytically and in commercial products. In this Review, prominent authors from around the world joined together to summarize the state of the art in understanding and using SERS and to predict what can be expected in the near future in terms of research, applications, and technological development. This Review is dedicated to SERS pioneer and our coauthor, the late Prof. Richard Van Duyne, whom we lost during the preparation of this article.
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Affiliation(s)
- Judith Langer
- CIC
biomaGUNE and CIBER-BBN, Paseo de Miramón 182, Donostia-San Sebastián 20014, Spain
| | | | - Javier Aizpurua
- Materials
Physics Center (CSIC-UPV/EHU), and Donostia
International Physics Center, Paseo Manuel de Lardizabal 5, Donostia-San
Sebastián 20018, Spain
| | - Ramon A. Alvarez-Puebla
- Departamento
de Química Física e Inorgánica and EMaS, Universitat Rovira i Virgili, Tarragona 43007, Spain
- ICREA-Institució
Catalana de Recerca i Estudis Avançats, Passeig Lluís Companys 23, Barcelona 08010, Spain
| | - Baptiste Auguié
- School
of Chemical and Physical Sciences, Victoria
University of Wellington, PO Box 600, Wellington 6140, New Zealand
- The
MacDiarmid
Institute for Advanced Materials and Nanotechnology, PO Box 600, Wellington 6140, New Zealand
- The Dodd-Walls
Centre for Quantum and Photonic Technologies, PO Box 56, Dunedin 9054, New Zealand
| | - Jeremy J. Baumberg
- NanoPhotonics
Centre, Cavendish Laboratory, University
of Cambridge, Cambridge CB3 0HE, United Kingdom
| | - Guillermo C. Bazan
- Department
of Materials and Chemistry and Biochemistry, University of California, Santa
Barbara, California 93106-9510, United States
| | - Steven E. J. Bell
- School
of Chemistry and Chemical Engineering, Queen’s
University of Belfast, Belfast BT9 5AG, United Kingdom
| | - Anja Boisen
- Department
of Micro- and Nanotechnology, The Danish National Research Foundation
and Villum Foundation’s Center for Intelligent Drug Delivery
and Sensing Using Microcontainers and Nanomechanics, Technical University of Denmark, Kongens Lyngby 2800, Denmark
| | - Alexandre G. Brolo
- Department
of Chemistry, University of Victoria, P.O. Box 3065, Victoria, BC V8W 3 V6, Canada
- Center
for Advanced Materials and Related Technologies, University of Victoria, Victoria, BC V8W 2Y2, Canada
| | - Jaebum Choo
- Department
of Chemistry, Chung-Ang University, Seoul 06974, South Korea
| | - Dana Cialla-May
- Leibniz
Institute of Photonic Technology Jena - Member of the research alliance “Leibniz Health Technologies”, Albert-Einstein-Str. 9, Jena 07745, Germany
- Institute
of Physical Chemistry and Abbe Center of Photonics, Friedrich-Schiller University Jena, Helmholtzweg 4, Jena 07745, Germany
| | - Volker Deckert
- Leibniz
Institute of Photonic Technology Jena - Member of the research alliance “Leibniz Health Technologies”, Albert-Einstein-Str. 9, Jena 07745, Germany
- Institute
of Physical Chemistry and Abbe Center of Photonics, Friedrich-Schiller University Jena, Helmholtzweg 4, Jena 07745, Germany
| | - Laura Fabris
- Department
of Materials Science and Engineering, Rutgers
University, 607 Taylor Road, Piscataway New Jersey 08854, United States
| | - Karen Faulds
- Department
of Pure and Applied Chemistry, University
of Strathclyde, Technology and Innovation Centre, 99 George Street, Glasgow G1 1RD, United Kingdom
| | - F. Javier García de Abajo
- ICREA-Institució
Catalana de Recerca i Estudis Avançats, Passeig Lluís Companys 23, Barcelona 08010, Spain
- The Barcelona
Institute of Science and Technology, Institut
de Ciencies Fotoniques, Castelldefels (Barcelona) 08860, Spain
| | - Royston Goodacre
- Department
of Biochemistry, Institute of Integrative Biology, University of Liverpool, Biosciences Building, Crown Street, Liverpool L69 7ZB, United Kingdom
| | - Duncan Graham
- Department
of Pure and Applied Chemistry, University
of Strathclyde, Technology and Innovation Centre, 99 George Street, Glasgow G1 1RD, United Kingdom
| | - Amanda J. Haes
- Department
of Chemistry, University of Iowa, Iowa City, Iowa 52242, United States
| | - Christy L. Haynes
- Department
of Chemistry, University of Minnesota, 207 Pleasant Street SE, Minneapolis, Minnesota 55455, United States
| | - Christian Huck
- Kirchhoff
Institute for Physics, University of Heidelberg, Im Neuenheimer Feld 227, Heidelberg 69120, Germany
| | - Tamitake Itoh
- Nano-Bioanalysis
Research Group, Health Research Institute, National Institute of Advanced Industrial Science and Technology, Takamatsu, Kagawa 761-0395, Japan
| | - Mikael Käll
- Department
of Physics, Chalmers University of Technology, Goteborg S412 96, Sweden
| | - Janina Kneipp
- Department
of Chemistry, Humboldt-Universität
zu Berlin, Brook-Taylor-Str. 2, Berlin-Adlershof 12489, Germany
| | - Nicholas A. Kotov
- Department
of Chemical Engineering, University of Michigan, Ann Arbor, Michigan 48109, United States
| | - Hua Kuang
- Key Lab
of Synthetic and Biological Colloids, Ministry of Education, International
Joint Research Laboratory for Biointerface and Biodetection, Jiangnan University, Wuxi, Jiangsu 214122, China
- State Key
Laboratory of Food Science and Technology, Jiangnan University, JiangSu 214122, China
| | - Eric C. Le Ru
- School
of Chemical and Physical Sciences, Victoria
University of Wellington, PO Box 600, Wellington 6140, New Zealand
- The
MacDiarmid
Institute for Advanced Materials and Nanotechnology, PO Box 600, Wellington 6140, New Zealand
- The Dodd-Walls
Centre for Quantum and Photonic Technologies, PO Box 56, Dunedin 9054, New Zealand
| | - Hiang Kwee Lee
- Division
of Chemistry and Biological Chemistry, School of Physical and Mathematical
Sciences, Nanyang Technological University, 21 Nanyang Link, Singapore 637371, Singapore
- Department
of Materials Science and Engineering, Stanford
University, Stanford, California 94305, United States
| | - Jian-Feng Li
- State Key
Laboratory of Physical Chemistry of Solid Surfaces, Collaborative
Innovation Center of Chemistry for Energy Materials, MOE Key Laboratory
of Spectrochemical Analysis & Instrumentation, Department of Chemistry,
College of Chemistry and Chemical Engineering, Xiamen University, Xiamen 361005, China
| | - Xing Yi Ling
- Division
of Chemistry and Biological Chemistry, School of Physical and Mathematical
Sciences, Nanyang Technological University, 21 Nanyang Link, Singapore 637371, Singapore
| | - Stefan A. Maier
- Chair in
Hybrid Nanosystems, Nanoinstitute Munich, Faculty of Physics, Ludwig-Maximilians-Universität München, Munich 80539, Germany
| | - Thomas Mayerhöfer
- Leibniz
Institute of Photonic Technology Jena - Member of the research alliance “Leibniz Health Technologies”, Albert-Einstein-Str. 9, Jena 07745, Germany
- Institute
of Physical Chemistry and Abbe Center of Photonics, Friedrich-Schiller University Jena, Helmholtzweg 4, Jena 07745, Germany
| | - Martin Moskovits
- Department
of Chemistry & Biochemistry, University
of California Santa Barbara, Santa Barbara, California 93106-9510, United States
| | - Kei Murakoshi
- Department
of Chemistry, Faculty of Science, Hokkaido
University, North 10 West 8, Kita-ku, Sapporo,
Hokkaido 060-0810, Japan
| | - Jwa-Min Nam
- Department
of Chemistry, Seoul National University, Seoul 08826, South Korea
| | - Shuming Nie
- Department of Bioengineering, University of Illinois at Urbana-Champaign, 1406 W. Green Street, Urbana, Illinois 61801, United States
| | - Yukihiro Ozaki
- Department
of Chemistry, School of Science and Technology, Kwansei Gakuin University, Sanda, Hyogo 669-1337, Japan
| | | | - Jorge Perez-Juste
- Departamento
de Química Física and CINBIO, University of Vigo, Vigo 36310, Spain
| | - Juergen Popp
- Leibniz
Institute of Photonic Technology Jena - Member of the research alliance “Leibniz Health Technologies”, Albert-Einstein-Str. 9, Jena 07745, Germany
- Institute
of Physical Chemistry and Abbe Center of Photonics, Friedrich-Schiller University Jena, Helmholtzweg 4, Jena 07745, Germany
| | - Annemarie Pucci
- Kirchhoff
Institute for Physics, University of Heidelberg, Im Neuenheimer Feld 227, Heidelberg 69120, Germany
| | - Stephanie Reich
- Department
of Physics, Freie Universität Berlin, Berlin 14195, Germany
| | - Bin Ren
- State Key
Laboratory of Physical Chemistry of Solid Surfaces, Collaborative
Innovation Center of Chemistry for Energy Materials, MOE Key Laboratory
of Spectrochemical Analysis & Instrumentation, Department of Chemistry,
College of Chemistry and Chemical Engineering, Xiamen University, Xiamen 361005, China
| | - George C. Schatz
- Department
of Chemistry, Northwestern University, Evanston, Illinois 60208-3113, United States
| | - Timur Shegai
- Department
of Physics, Chalmers University of Technology, Goteborg S412 96, Sweden
| | - Sebastian Schlücker
- Physical
Chemistry I, Department of Chemistry and Center for Nanointegration
Duisburg-Essen, University of Duisburg-Essen, Essen 45141, Germany
| | - Li-Lin Tay
- National
Research Council Canada, Metrology Research
Centre, Ottawa K1A0R6, Canada
| | - K. George Thomas
- School
of Chemistry, Indian Institute of Science
Education and Research Thiruvananthapuram, Vithura Thiruvananthapuram 695551, India
| | - Zhong-Qun Tian
- State Key
Laboratory of Physical Chemistry of Solid Surfaces, Collaborative
Innovation Center of Chemistry for Energy Materials, MOE Key Laboratory
of Spectrochemical Analysis & Instrumentation, Department of Chemistry,
College of Chemistry and Chemical Engineering, Xiamen University, Xiamen 361005, China
| | - Richard P. Van Duyne
- Department
of Chemistry, Northwestern University, Evanston, Illinois 60208-3113, United States
| | - Tuan Vo-Dinh
- Fitzpatrick
Institute for Photonics, Department of Biomedical Engineering, and
Department of Chemistry, Duke University, 101 Science Drive, Box 90281, Durham, North Carolina 27708, United States
| | - Yue Wang
- Department
of Chemistry, College of Sciences, Northeastern
University, Shenyang 110819, China
| | - Katherine A. Willets
- Department
of Chemistry, Temple University, Philadelphia, Pennsylvania 19122, United States
| | - Chuanlai Xu
- Key Lab
of Synthetic and Biological Colloids, Ministry of Education, International
Joint Research Laboratory for Biointerface and Biodetection, Jiangnan University, Wuxi, Jiangsu 214122, China
- State Key
Laboratory of Food Science and Technology, Jiangnan University, JiangSu 214122, China
| | - Hongxing Xu
- School
of Physics and Technology and Institute for Advanced Studies, Wuhan University, Wuhan 430072, China
| | - Yikai Xu
- School
of Chemistry and Chemical Engineering, Queen’s
University of Belfast, Belfast BT9 5AG, United Kingdom
| | - Yuko S. Yamamoto
- School
of Materials Science, Japan Advanced Institute
of Science and Technology, Nomi, Ishikawa 923-1292, Japan
| | - Bing Zhao
- State Key
Laboratory of Supramolecular Structure and Materials, Jilin University, Changchun 130012, China
| | - Luis M. Liz-Marzán
- CIC
biomaGUNE and CIBER-BBN, Paseo de Miramón 182, Donostia-San Sebastián 20014, Spain
- Ikerbasque,
Basque Foundation for Science, Bilbao 48013, Spain
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7
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Pyrak E, Krajczewski J, Kowalik A, Kudelski A, Jaworska A. Surface Enhanced Raman Spectroscopy for DNA Biosensors-How Far Are We? Molecules 2019; 24:E4423. [PMID: 31817059 PMCID: PMC6943648 DOI: 10.3390/molecules24244423] [Citation(s) in RCA: 40] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2019] [Revised: 11/28/2019] [Accepted: 11/29/2019] [Indexed: 12/20/2022] Open
Abstract
A sensitive and accurate identification of specific DNA fragments (usually containing a mutation) can influence clinical decisions. Standard methods routinely used for this type of detection are PCR (Polymerase Chain Reaction, and its modifications), and, less commonly, NGS (Next Generation Sequencing). However, these methods are quite complicated, requiring time-consuming, multi-stage sample preparation, and specially trained staff. Usually, it takes weeks for patients to obtain their results. Therefore, different DNA sensors are being intensively developed by many groups. One technique often used to obtain an analytical signal from DNA sensors is Raman spectroscopy. Its modification, surface-enhanced Raman spectroscopy (SERS), is especially useful for practical analytical applications due to its extra low limit of detection. SERS takes advantage of the strong increase in the efficiency of Raman signal generation caused by a local electric field enhancement near plasmonic (typically gold and silver) nanostructures. In this condensed review, we describe the most important types of SERS-based nanosensors for genetic studies and comment on their potential for becoming diagnostic tools.
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Affiliation(s)
- Edyta Pyrak
- Faculty of Chemistry, University of Warsaw, 1 Pasteur St., 02-093 Warsaw, Poland; (E.P.); (J.K.)
- Nencki Institute of Experimental Biology of Polish Academy of Sciences, 3 Pasteur St., 02-093 Warsaw, Poland
| | - Jan Krajczewski
- Faculty of Chemistry, University of Warsaw, 1 Pasteur St., 02-093 Warsaw, Poland; (E.P.); (J.K.)
| | - Artur Kowalik
- Holy Cross Cancer Center, 3 Stefana Artwińskiego St., 25-734 Kielce, Poland
| | - Andrzej Kudelski
- Faculty of Chemistry, University of Warsaw, 1 Pasteur St., 02-093 Warsaw, Poland; (E.P.); (J.K.)
| | - Aleksandra Jaworska
- Faculty of Chemistry, University of Warsaw, 1 Pasteur St., 02-093 Warsaw, Poland; (E.P.); (J.K.)
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8
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Lu G, Forbes TZ, Haes AJ. SERS detection of uranyl using functionalized gold nanostars promoted by nanoparticle shape and size. Analyst 2018; 141:5137-43. [PMID: 27326897 DOI: 10.1039/c6an00891g] [Citation(s) in RCA: 60] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
The radius of curvature of gold (Au) nanostar tips but not the overall particle dimensions can be used for understanding the large and quantitative surface-enhanced Raman scattering (SERS) signal of the uranyl (UO2)(2+) moiety. The engineered roughness of the Au nanostar architecture and the distance between the gold surface and uranyl cations are promoted using carboxylic acid terminated alkanethiols containing 2, 5, and 10 methylene groups. By systematically varying the self-assembled monolayer (SAM) thickness with these molecules, the localized surface plasmon resonance (LSPR) spectral properties are used to quantify the SAM layer thickness and to promote uranyl coordination to the Au nanostars in neutral aqueous solutions. Successful uranyl detection is demonstrated for all three functionalized Au nanostar samples as indicated by enhanced signals and red-shifts in the symmetric U(vi)-O stretch. Quantitative uranyl detection is achieved by evaluating the integrated area of these bands in the uranyl fingerprint window. By varying the concentration of uranyl, similar free energies of adsorption are observed for the three carboxylic acid terminated functionalized Au nanostar samples indicating similar coordination to uranyl, but the SERS signals scale inversely with the alkanethiol layer thickness. This distance dependence follows previously established models assuming that roughness features associated with the radius of curvature of the tips are considered. These results indicate that SERS signals using functionalized Au nanostar substrates can provide quantitative detection of small molecules and that the tip architecture plays an important role in understanding the resulting SERS intensities.
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Affiliation(s)
- Grace Lu
- University of Iowa, Department of Chemistry, Iowa City, IA 52242, USA.
| | - Tori Z Forbes
- University of Iowa, Department of Chemistry, Iowa City, IA 52242, USA.
| | - Amanda J Haes
- University of Iowa, Department of Chemistry, Iowa City, IA 52242, USA.
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9
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Luan J, Morrissey JJ, Wang Z, Derami HG, Liu KK, Cao S, Jiang Q, Wang C, Kharasch ED, Naik RR, Singamaneni S. Add-on plasmonic patch as a universal fluorescence enhancer. LIGHT, SCIENCE & APPLICATIONS 2018; 7:29. [PMID: 30839611 PMCID: PMC6107004 DOI: 10.1038/s41377-018-0027-8] [Citation(s) in RCA: 37] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/19/2017] [Revised: 04/09/2018] [Accepted: 04/25/2018] [Indexed: 05/13/2023]
Abstract
Fluorescence-based techniques are the cornerstone of modern biomedical optics, with applications ranging from bioimaging at various scales (organelle to organism) to detection and quantification of a wide variety of biological species of interest. However, the weakness of the fluorescence signal remains a persistent challenge in meeting the ever-increasing demand to image, detect, and quantify biological species with low abundance. Here, we report a simple and universal method based on a flexible and conformal elastomeric film with adsorbed plasmonic nanostructures, which we term a "plasmonic patch," that provides large (up to 100-fold) and uniform fluorescence enhancement on a variety of surfaces through simple transfer of the plasmonic patch to the surface. We demonstrate the applications of the plasmonic patch in improving the sensitivity and limit of detection (by more than 100 times) of fluorescence-based immunoassays implemented in microtiter plates and in microarray format. The novel fluorescence enhancement approach presented here represents a disease, biomarker, and application agnostic ubiquitously applicable fundamental and enabling technology to immediately improve the sensitivity of existing analytical methodologies in an easy-to-handle and cost-effective manner, without changing the original procedures of the existing techniques.
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Affiliation(s)
- Jingyi Luan
- Department of Mechanical Engineering and Materials Science, Institute of Materials Science and Engineering, Washington University in St. Louis, St Louis, MO 63130 USA
| | - Jeremiah J. Morrissey
- Department of Anesthesiology, Washington University in St. Louis, St. Louis, MO 63110 USA
- Siteman Cancer Center, Washington University in St. Louis, St. Louis, MO 63110 USA
| | - Zheyu Wang
- Department of Mechanical Engineering and Materials Science, Institute of Materials Science and Engineering, Washington University in St. Louis, St Louis, MO 63130 USA
| | - Hamed Gholami Derami
- Department of Mechanical Engineering and Materials Science, Institute of Materials Science and Engineering, Washington University in St. Louis, St Louis, MO 63130 USA
| | - Keng-Ku Liu
- Department of Mechanical Engineering and Materials Science, Institute of Materials Science and Engineering, Washington University in St. Louis, St Louis, MO 63130 USA
| | - Sisi Cao
- Department of Mechanical Engineering and Materials Science, Institute of Materials Science and Engineering, Washington University in St. Louis, St Louis, MO 63130 USA
| | - Qisheng Jiang
- Department of Mechanical Engineering and Materials Science, Institute of Materials Science and Engineering, Washington University in St. Louis, St Louis, MO 63130 USA
| | - Congzhou Wang
- Department of Mechanical Engineering and Materials Science, Institute of Materials Science and Engineering, Washington University in St. Louis, St Louis, MO 63130 USA
| | - Evan D. Kharasch
- Department of Anesthesiology, Washington University in St. Louis, St. Louis, MO 63110 USA
- Siteman Cancer Center, Washington University in St. Louis, St. Louis, MO 63110 USA
- Department of Biochemistry and Molecular Biophysics, Washington University in St. Louis, St. Louis, MO 63110 USA
- The Center for Clinical Pharmacology, St. Louis College of Pharmacy and Washington University School of Medicine, St. Louis, MO USA
| | - Rajesh R. Naik
- 711th Human Performance Wing, Air Force Research Laboratory, Wright-Patterson Air Force Base, Dayton, OH 45433 USA
| | - Srikanth Singamaneni
- Department of Mechanical Engineering and Materials Science, Institute of Materials Science and Engineering, Washington University in St. Louis, St Louis, MO 63130 USA
- Siteman Cancer Center, Washington University in St. Louis, St. Louis, MO 63110 USA
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10
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Shen Y, Gee MY, Greytak AB. Purification technologies for colloidal nanocrystals. Chem Commun (Camb) 2018; 53:827-841. [PMID: 27942615 DOI: 10.1039/c6cc07998a] [Citation(s) in RCA: 48] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Almost all applications of colloidal nanocrystals require some type of purification or surface modification process following nanocrystal growth. Nanocrystal purification - the separation of nanocrystals from undesired solution components - can perturb the surface chemistry and thereby the physical properties of colloidal nanocrystals due to changes in solvent, solute concentrations, and exposure of the nanocrystal surface to oxidation or hydrolysis. For example, nanocrystal quantum dots frequently exhibit decreased photoluminescence brightness after precipitation from the growth solvent and subsequent redissolution. Consequently, purification is an integral part of the synthetic chemistry of colloidal nanocrystals, and the effect of purification methods must be considered in order to accurately compare and predict the behavior of otherwise similar nanocrystal samples. In this Feature Article we examine established and emerging approaches to the purification of colloidal nanoparticles from a nanocrystal surface chemistry viewpoint. Purification is generally achieved by exploiting differences in properties between the impurities and the nanoparticles. Three distinct properties are typically manipulated: polarity (relative solubility), electrophoretic mobility, and size. We discuss precipitation, extraction, electrophoretic methods, and size-based methods including ultracentrifugation, ultrafiltration, diafiltration, and size-exclusion chromatography. The susceptibility of quantum dots to changes in surface chemistry, with changes in photoluminescence decay associated with surface chemical changes, extends even into the case of core/shell structures. Accordingly, the goal of a more complete description of quantum dot surface chemistry has been a driver of innovation in colloidal nanocrystal purification methods. We specifically examine the effect of purification on surface chemistry and photoluminescence in quantum dots as an example of the challenges associated with nanocrystal purification and how improved understanding can result from increasingly precise techniques, and associated surface-sensitive analytical methods.
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Affiliation(s)
- Yi Shen
- Department of Chemistry and Biochemistry, University of South Carolina, Columbia, SC 29208, USA.
| | - Megan Y Gee
- Department of Chemistry and Biochemistry, University of South Carolina, Columbia, SC 29208, USA.
| | - A B Greytak
- Department of Chemistry and Biochemistry, University of South Carolina, Columbia, SC 29208, USA. and USC Nanocenter, University of South Carolina, Columbia, SC 29208, USA
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11
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Xi W, Shrestha BK, Haes AJ. Promoting Intra- and Intermolecular Interactions in Surface-Enhanced Raman Scattering. Anal Chem 2017; 90:128-143. [DOI: 10.1021/acs.analchem.7b04225] [Citation(s) in RCA: 50] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Affiliation(s)
- Wenjing Xi
- Department of Chemistry, University of Iowa, Iowa City, Iowa, 55242 United States
| | - Binaya K. Shrestha
- Department of Chemistry, University of Iowa, Iowa City, Iowa, 55242 United States
| | - Amanda J. Haes
- Department of Chemistry, University of Iowa, Iowa City, Iowa, 55242 United States
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12
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Qiu TA, Torelli MD, Vartanian AM, Rackstraw NB, Buchman JT, Jacob LM, Murphy CJ, Hamers RJ, Haynes CL. Quantification of Free Polyelectrolytes Present in Colloidal Suspension, Revealing a Source of Toxic Responses for Polyelectrolyte-Wrapped Gold Nanoparticles. Anal Chem 2017; 89:1823-1830. [DOI: 10.1021/acs.analchem.6b04161] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Affiliation(s)
- Tian A. Qiu
- Department
of Chemistry, University of Minnesota, 207 Pleasant Street SE, Minneapolis, Minnesota 55455, United States
| | - Marco D. Torelli
- Department
of Chemistry, University of Wisconsin—Madison, 1101 University Avenue, Madison, Wisconsin 53706, United States
| | - Ariane M. Vartanian
- Department
of Chemistry, University of Illinois at Urbana−Champaign, 600 S. Mathews Avenue, Urbana, Illinois 61801, United States
| | - Nathan B. Rackstraw
- Department
of Chemistry, University of Minnesota, 207 Pleasant Street SE, Minneapolis, Minnesota 55455, United States
| | - Joseph T. Buchman
- Department
of Chemistry, University of Minnesota, 207 Pleasant Street SE, Minneapolis, Minnesota 55455, United States
| | - Lisa M. Jacob
- Department
of Chemistry, University of Illinois at Urbana−Champaign, 600 S. Mathews Avenue, Urbana, Illinois 61801, United States
| | - Catherine J. Murphy
- Department
of Chemistry, University of Illinois at Urbana−Champaign, 600 S. Mathews Avenue, Urbana, Illinois 61801, United States
| | - Robert J. Hamers
- Department
of Chemistry, University of Wisconsin—Madison, 1101 University Avenue, Madison, Wisconsin 53706, United States
| | - Christy L. Haynes
- Department
of Chemistry, University of Minnesota, 207 Pleasant Street SE, Minneapolis, Minnesota 55455, United States
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13
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Ma C, Trujillo MJ, Camden JP. Nanoporous Silver Film Fabricated by Oxygen Plasma: A Facile Approach for SERS Substrates. ACS APPLIED MATERIALS & INTERFACES 2016; 8:23978-84. [PMID: 27551811 DOI: 10.1021/acsami.6b08191] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/17/2023]
Abstract
Nanoporous metal films are promising substrates for surfaced-enhanced Raman scattering (SERS) measurement, owing to their homogeneity, large surface area, and abundant hot-spots. Herein, a facile procedure was developed to fabricate nanoporous Ag film on various substrate surfaces. Thermally deposited Ag film was first treated with O2 plasma, resulting in porous Ag/AgxO film (AgxO-NF) with nanoscale feature. Sodium citrate was then used to reduce AgxO to Ag, forming nanoporous Ag film (AgNF) with similar morphology. The AgNF substrate demonstrates 30-fold higher Raman intensity than Ag film over polystyrene nanospheres (d = 600 nm) using 4-mercaptobenzoic acid (4-MBA) as the sensing molecule. Comparing with ordinary Raman measurement on 4-MBA solution, an enhancement factor of ∼6 × 10(6) was determined for AgNF. The AgNF substrate was evaluated for benzoic acid, 4-nitrophenol, and 2-mercaptoethanesulfonate, showing high SERS sensitivity for chemicals that bind weakly to Ag surface and molecules with relatively small Raman cross section at micromolar concentration. In addition to its simplicity, the procedure can be applied to various materials such as transparency film, filter paper, hard polystyrene film, and aluminum foil, revealing similar Raman sensitivity. By testing the durability of the substrate, we found that the AgxO films can be stored in ambient conditions for more than 90 days and still deliver the same SERS intensity if the films are treated with sodium citrate before use. These results demonstrate the advantage of the proposed approach for mass production of low-cost, sensitive, and durable SERS substrates. The transferable nature of these AgNF to different flexible surfaces also allows their easy integration with other sensing schemes.
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Affiliation(s)
- Chaoxiong Ma
- Department of Chemistry and Biochemistry, University of Notre Dame , Notre Dame, Indiana 46556, United States
| | - Michael J Trujillo
- Department of Chemistry and Biochemistry, University of Notre Dame , Notre Dame, Indiana 46556, United States
| | - Jon P Camden
- Department of Chemistry and Biochemistry, University of Notre Dame , Notre Dame, Indiana 46556, United States
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14
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Xu LJ, Lei ZC, Li J, Zong C, Yang CJ, Ren B. Label-Free Surface-Enhanced Raman Spectroscopy Detection of DNA with Single-Base Sensitivity. J Am Chem Soc 2015; 137:5149-54. [DOI: 10.1021/jacs.5b01426] [Citation(s) in RCA: 317] [Impact Index Per Article: 35.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Affiliation(s)
- Li-Jia Xu
- State Key Laboratory of Physical Chemistry of Solid Surfaces, Collaborative Innovation Center of Chemistry for Energy Materials, The MOE Key Laboratory of Spectrochemical Analysis & Instrumentation, ‡Department of Chemistry, §Key Laboratory of Chemical Biology of Fujian Province, and ∥Department of Chemical Biology, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen 361005, China
| | - Zhi-Chao Lei
- State Key Laboratory of Physical Chemistry of Solid Surfaces, Collaborative Innovation Center of Chemistry for Energy Materials, The MOE Key Laboratory of Spectrochemical Analysis & Instrumentation, ‡Department of Chemistry, §Key Laboratory of Chemical Biology of Fujian Province, and ∥Department of Chemical Biology, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen 361005, China
| | - Jiuxing Li
- State Key Laboratory of Physical Chemistry of Solid Surfaces, Collaborative Innovation Center of Chemistry for Energy Materials, The MOE Key Laboratory of Spectrochemical Analysis & Instrumentation, ‡Department of Chemistry, §Key Laboratory of Chemical Biology of Fujian Province, and ∥Department of Chemical Biology, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen 361005, China
| | - Cheng Zong
- State Key Laboratory of Physical Chemistry of Solid Surfaces, Collaborative Innovation Center of Chemistry for Energy Materials, The MOE Key Laboratory of Spectrochemical Analysis & Instrumentation, ‡Department of Chemistry, §Key Laboratory of Chemical Biology of Fujian Province, and ∥Department of Chemical Biology, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen 361005, China
| | - Chaoyong James Yang
- State Key Laboratory of Physical Chemistry of Solid Surfaces, Collaborative Innovation Center of Chemistry for Energy Materials, The MOE Key Laboratory of Spectrochemical Analysis & Instrumentation, ‡Department of Chemistry, §Key Laboratory of Chemical Biology of Fujian Province, and ∥Department of Chemical Biology, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen 361005, China
| | - Bin Ren
- State Key Laboratory of Physical Chemistry of Solid Surfaces, Collaborative Innovation Center of Chemistry for Energy Materials, The MOE Key Laboratory of Spectrochemical Analysis & Instrumentation, ‡Department of Chemistry, §Key Laboratory of Chemical Biology of Fujian Province, and ∥Department of Chemical Biology, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen 361005, China
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15
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Volkert AA, Pierre MCS, Shrestha B, Haes AJ. Implications of sample aging on the formation of internally etched silica coated gold nanoparticles. RSC Adv 2015. [DOI: 10.1039/c4ra15443f] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Local refractive index sensitivity modelling using the plasmonic properties of gold nanospheres assists in the elucidation of the nanoparticle-rattle formation as a function of sample age and storage conditions.
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16
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Huang D, Cui J, Chen X. A morpholinium surfactant crystallization induced formation of Au nanoparticle sheet-like assemblies with uniform SERS activity. Colloids Surf A Physicochem Eng Asp 2014. [DOI: 10.1016/j.colsurfa.2014.05.027] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
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17
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Wolosiuk A, Tognalli NG, Martínez ED, Granada M, Fuertes MC, Troiani H, Bilmes SA, Fainstein A, Soler-Illia GJAA. Silver nanoparticle-mesoporous oxide nanocomposite thin films: a platform for spatially homogeneous SERS-active substrates with enhanced stability. ACS APPLIED MATERIALS & INTERFACES 2014; 6:5263-5272. [PMID: 24621107 DOI: 10.1021/am500631f] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
We introduce a nanoparticle-mesoporous oxide thin film composite (NP-MOTF) as low-cost and straightforward sensing platforms for surface-enhanced Raman Spectroscopy (SERS). Titania, zirconia, and silica mesoporous matrices templated with Pluronics F-127 were synthesized via evaporation-induced self-assembly and loaded with homogeneously dispersed Ag nanoparticles by soft reduction or photoreduction. Both methods give rise to uniform and reproducible Raman signals using 4-mercaptopyridine as a probe molecule. Details on stability and reproducibility of the Raman enhancement are discussed. Extensions in the design of these composite structures were explored including detection of nonthiolated molecules, such as rhodamine 6-G or salicylic acid, patterning techniques for locating the enhancement regions and bilayered mesoporous structures to provide additional control on the environment, and potential size-selective filtration. These inorganic oxide-metal composites stand as extremely simple, reproducible, and versatile platforms for Raman spectroscopy analysis.
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Affiliation(s)
- Alejandro Wolosiuk
- Gerencia Química, Centro Atómico Constituyentes, Comisión Nacional de Energía Atómica (CNEA) , Av. Gral Paz 1499 B1650KNA San Martín, Buenos Aires, Argentina
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18
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Jiang X, Yang M, Meng Y, Jiang W, Zhan J. Cysteamine-modified silver nanoparticle aggregates for quantitative SERS sensing of pentachlorophenol with a portable Raman spectrometer. ACS APPLIED MATERIALS & INTERFACES 2013; 5:6902-6908. [PMID: 23820578 DOI: 10.1021/am401718p] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
Cysteamine-modified silver nanoparticle aggregates has been fabricated for pentachlorophenol (PCP) sensing by surface-enhanced Raman spectroscopy (SERS) using a portable Raman spectrometer. The cysteamine monolayers could preconcentrate PCP close to the substrate surface through the electrostatic interaction, which makes the SERS detection of PCP possible. Moreover, the Raman bands of cysteamine could be used as the internal spectral reference in the quantitative analysis. Qualitative detection of PCP was carried out by SERS without any sample pretreatment. Quantitative analysis of PCP was further realized based on the prepared substrate, as the log-log plot of normalized SERS intensity of PCP versus its concentrations exhibits a good linear relationship. The SERS signals collected on 20 randomly selected points show that the relative standard deviation of the normalized Raman intensity is 5.8%, which indicates the substrate had good uniformity. The PCP sensor also shows good long-term stability in the analyte solution. The substrate was cyclic immersed into PCP and methanol solution; after several cycles, the sensor still had good adsorption to PCP, which revealed the sensor has good reusability. Coupling with a portable Raman spectrometer, the cysteamine-modified silver nanoparticle aggregates have the potential to be used for in situ and routine SERS analysis of PCP in environmental samples.
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Affiliation(s)
- Xiaohong Jiang
- Key Laboratory of Colloid and Interface Chemistry, Ministry of Education, Department of Chemistry, Shandong University, Jinan 250100, China
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