Download or read book Generation and Optical Properties of Silver Surface Enhanced Raman Scattering Substrates written by Peter Christian Andersen and published by . This book was released on 2003 with total page 252 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Chemical Resonance Effects in Surface enhanced Raman Scattering of Nucleic Acid Silver Composites written by Lindsay Michelle Freeman and published by . This book was released on 2016 with total page 132 pages. Available in PDF, EPUB and Kindle. Book excerpt: Although surface-enhanced Raman spectroscopy (SERS) has been a valuable tool for chemical detection, the understanding of the contributions of the chemical enhancement effect in nucleic acid-silver composites remains limited. Nucleic acid-silver composites have unique optical properties such as fluorescence and enhanced Raman generation, and thus need to be further analyzed and characterized. In this dissertation, the static polarizability chemical effect is used to determine the preferential binding sites of nucleic acids to silver nanoparticles. The binding configuration dictates the optical properties, so it is imperative to determine which atoms are binding to the silver structures. Time-dependent density functional theory simulations are used to calculate the Raman frequencies of several systems and are then quantitatively compared to experimental measurements. The approximate composition of the binding sites for each nucleic acid to silver films is determined using the simulated Raman correlation spectroscopy process. In the second part of the dissertation, the charge-transfer effect in nucleic acid-silver composites is harnessed in order to selectively enhance or reduce the SERS signals via wavelength selection. Depending on the molecular properties of the nucleic acids, the optimal excitation wavelength shifts from visible to near-infrared. The properties can be taken advantage of to better control the systems under study. The charge-transfer effect is further understood by utilizing a thin film of aluminum oxide to prevent electron transfer from occurring, and thus enabling the calculation of the order of magnitude of the charge-transfer effect. The characterization of nucleic acid-silver composites is imperative to fully understanding the unique and exciting properties that these systems provide. While SERS has been limited in terms of DNA detection or sequencing, the restrictions have been caused by insufficient information. This dissertation offers additional information on the systems and explains the discrepancies seen in previous measurements of nucleic acid-silver composites.

Download or read book Surface Enhanced Vibrational Spectroscopy written by Ricardo Aroca and published by John Wiley & Sons. This book was released on 2006-05-01 with total page 260 pages. Available in PDF, EPUB and Kindle. Book excerpt: Surface Enhanced Vibrational Spectroscopy (SEVS) has reached maturity as an analytical technique, but until now there has been no single work that describes the theory and experiments of SEVS. This book combines the two important techniques of surface-enhanced Raman scattering (SERS) and surface-enhanced infrared (SEIR) into one text that serves as the definitive resource on SEVS. Discusses both the theory and the applications of SEVS and provides an up-to-date study of the state of the art Offers interpretations of SEVS spectra for practicing analysts Discusses interpretation of SEVS spectra, which can often be very different to the non-enhanced spectrum - aids the practicing analyst

Download or read book Surface Enhanced Raman Scattering New Theoretical Approaches Materials and Strategies written by Ivano Alessandri and published by Frontiers Media SA. This book was released on 2020-03-25 with total page 175 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Water soluble Vitamin Assays in Human Nutrition written by G.F.M. Ball and published by Springer. This book was released on 2012-11-05 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: ...this is a valuable addition to the food analyst;s library. It brings together a well balanced account of the methods available an the literature cited will provide the analyst with all the details needed for setting up water-soluble vitamin assays and further reading to understand why these vitamins are important to those concerned with human nutrition. ' - International Journal of Food Science and Technology This book is of practical use as a tool and reference work of laboratory managers, senior analysts and laboratory technicians in food and vitamin manufactrurinf companies, for those in govenment and research institutes and for medical researchers, public analyst and nutritionist, It can also be recommended for a broad audience including lectures, students of natural sciences and food technologist. - lesbensm Wiss und Technol.'I recommend Water-soluble vitamins Assays in Human Nutrition not only to scientist in academia and industry and students in all food related fields as a valuable and easily used reference... it wll most likely be the first book I reach for when the inevitable question arises.April 1994Price: 115.00UK

Download or read book Frontiers of Surface Enhanced Raman Scattering written by Yukihiro Ozaki and published by John Wiley & Sons. This book was released on 2014-02-19 with total page 466 pages. Available in PDF, EPUB and Kindle. Book excerpt: A comprehensive presentation of Surface-Enhanced Raman Scattering (SERS) theory, substrate fabrication, applications of SERS to biosystems, chemical analysis, sensing and fundamental innovation through experimentation. Written by internationally recognized editors and contributors. Relevant to all those within the scientific community dealing with Raman Spectroscopy, i.e. physicists, chemists, biologists, material scientists, physicians and biomedical scientists. SERS applications are widely expanding and the technology is now used in the field of nanotechnologies, applications to biosystems, nonosensors, nanoimaging and nanoscience.

Download or read book Spark Ablation written by Andreas Schmidt-Ott and published by CRC Press. This book was released on 2019-12-19 with total page 292 pages. Available in PDF, EPUB and Kindle. Book excerpt: Spark ablation has been used worldwide for decades. However, in many fields, the special properties of nanoparticles, which come into play especially for sizes

Download or read book Fabrication of Surface Enhanced Raman Scattering Substrates by Controlled Assembly and Morphology Tuning of Gold Nanoparticles written by Agampodi Swarnapali De Silva Indrasekara and published by . This book was released on 2014 with total page 142 pages. Available in PDF, EPUB and Kindle. Book excerpt: The design and fabrication of nanoparticles (NPs) and NP assemblies to sustain intense electromagnetic field enhancement for surface enhanced Raman scattering (SERS)-based imaging and sensing have recently gained significant attention. In SERS, the intrinsic optical properties of plasmonic NPs are used to overcome the relatively low Raman cross-sections and thereby increase sensitivity. Sharp features in anisotropic NPs and interparticle gaps within NP assemblies have been identified as the locations where the highest SERS enhancements can be achieved, also known as "hot spots". Many attempts have been reported that deal with the bottom-up assembly of NPs to achieve highly reproducible, sensitive, and well characterized SERS substrates, but it still remains a challenge to attain monodisperse, highly reproducible "hot spots" and directional assembly. The focus of this dissertation is to develop synthetic protocols for controlled engineering of NPs with SERS "hot spots", and thereby to contribute to the advancement of SERS-based sensing and imaging applications. In this dissertation, the development of SERS substrates has evolved from dimers of spherical gold NPs (SP), to star-shaped gold NPs (ST), and finally to assembled superstructures of ST and SPs. The kinetically controlled assembly of SPs into dimers was achieved by using Raman active dithiolated linker molecules, with the highest yield reported for this method to the best of our knowledge, leading to SERS tags with a reproducible SERS enhancement on the order of 105. NP dimers, surface-functionalized to target U87 glioblastoma cancer cells, demonstrated a fast, reliable, and selective SERS-based detection of the diseased cells that outperforms fluorescence. The morphology of the STs was modified to possess longer and sharper spikes with a narrower tip curvature thereby increasing the electromagnetic field localization at the tips. SERS substrates were designed by periodically and reproducibly immobilizing STs on a planar substrate with high surface coverage and limited to no clustering, thus enabling femtomolar detection of organic analytes with an outstanding 109 SERS enhancement. Finally, the core-satellite assemblies of ST with SPs were achieved through conjugation linker chemistry. These assemblies demonstrated SERS enhancement of two orders of magnitudes greater than isolated STs thereby improving the sensitivity of potential SERS-based imaging and sensing applications.

Download or read book Plasmonic Porous Ceramics for Molecule Detection Via Surface enhanced Raman Scattering written by Tongwei Guo and published by . This book was released on 2024 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: A plasmonic porous ceramic can be defined as a three-dimensional porous ceramic matrix with embedded plasmonic nanoparticles. Like regular ceramics, this material class shows advantages like high temperature and pressure stability, chemically inertness, along with dielectric properties. Plasmonic porous ceramics have a high potential for a broad range of applications in various fields, for example ultrasensitive chemical detection under high temperature/high-pressure conditions, for biomarker detection in biological systems or for highly efficient energy generation through plasmonic photothermal heating. In general, plasmonic materials are developed because of their ability of confining and manipulating electromagnetic radiation, which enables highly sensitive and rapid detection of molecules, for example via surface-enhanced Raman spectroscopy (SERS). Typical plasmonic nanoparticles used for SERS are gold and silver nanoparticles. Because of the high density of mobile electrons, plasmonic nanoparticles (Au, Ag nanoparticles) can couple with the electromagnetic radiation of wavelengths that are far larger than the nanoparticles themselves. Light absorption and scattering by plasmonic nanoparticles can be tailored by varying their size, geometry and relative positions. This thesis aims to present the new concept of plasmonic porous ceramic by introducing plasmonic nanostructures in open-cell foam ceramics and to investigate application possibilities of this substrate due to its advanced optical properties. These optical properties of the plasmonic porous ceramic lead to significant magnification of the Raman scattering signal, that enables this substrate serving as SERS substrate and providing molecule “fingerprint” for sensitive and real-time detection. Therefore, the first cornerstone of this work is proof-of-principle of plasmonic porous ceramics. Open porous ceramic structures based on zirconia-toughened alumina (ZTA) were processed, sintered and functionalized with silver nanoparticles. The Raman enhancement of the plasmonic structures was analyzed as a function of the amount of deposited silver nanoparticles, pore diameter and strut diameter of the ceramic structure using the probe molecule pyridine. Flat substrates of the same chemical composition and non-porous fragments of the porous structure were used for comparison. The Raman signal is found to be significantly augmented by the porous structure compared to that collected on flat substrates with similar composition. Accordingly, the plasmonic porous ceramics were supposed to be well suited as 3D SERS substrates, allowing real-time Raman sensing of trace amounts of molecules.

Download or read book Improving Analytical Utility of Surface Enhanced Raman Spectroscopy Through Unique Lithographic Substrate Development written by Sabrina Marie Wells and published by . This book was released on 2012 with total page 173 pages. Available in PDF, EPUB and Kindle. Book excerpt: Surface enhanced Raman spectroscopy (SERS) has the potential to be a useful analytical technique due to large signal enhancements. Unfortunately, SERS has several drawbacks, including a lack of reproducibility, which inhibits it from being a practical option. These large signals often arise from "hot spots" of extremely high enhancement on nanofeatured metallic substrates, the most common being comprised of aggregated silver colloid. It is difficult to reproducibly create these hot spots due to the randomness of the colloid substrates. However, through controlled substrate fabrication, many problems associated with SERS analysis can be overcome. Electron beam lithography (EBL) combined with reactive-ion etching (RIE) was used to fabricate a wide variety of aggregate-like structures that allow for methodically surveying the system to determine if areas of high enhancement are present. Any well performing areas were then recreated consistently to produce areas of similar enhancement. While the aforementioned "combinatorial" approach has its advantages, simple structures are often easier to fabricate and theoretically model. As such, a single structure consisting of a metal disc on a silicon pillar was created. A variety of tests were performed on these structures to determine the overall utility of the simple pillar system. The system was found to possess extremely high enhancement, making it an ideal system to both theoretically model and test experimentally. The system also has strong enough overall signal to allow for potential analytical implications. Studies were also conducted to determine the feasibility of using a strong enhancing silicon nanopillar system to make analytical measurements without a metal surface present. A special fabrication process using EBL and RIE was used to created tall, high aspect ratio pillars of known diameters. These nanopillars were then observed to exhibit special optical properties not seen in bulk silicon. Aside from modest Raman enhancement, these structures also demonstrated the ability to enhance the signal of specific analytes similar to SERS. Surface enhanced fluorescence (SEF) was also observed for different analytes, allowing for a variety of potential analytical areas.

Download or read book A Chemical Free Approach for Increasing the Biochemical Surface enhanced Raman Spectroscopy SERS based Sensing Capabilities of Colloidal Silver Nanoparticles written by Kevin Michael Dorney and published by . This book was released on 2014 with total page 170 pages. Available in PDF, EPUB and Kindle. Book excerpt: The unique optoelectronic properties of silver nanoparticles (AgNPs) have led to their explosive use in a multitude of both research and industrial settings in recent years. Localized surface plasmon resonance (LSPR) exhibited by AgNPs has been exploited extensively as a nano-scale probe in a variety of spectroscopic detection modalities, particularly in surface-enhanced Raman spectroscopy (SERS). The SERS effect is highly dependent upon the LSPR interaction with optical laser frequencies, thus optimization of LSPR via specific control of AgNP dimensionality and composition of the surrounding medium is vital for increasing the efficacy of SERS-based nano-sensing. This work aimed to augment LSPR of AgNPs by applying the chemical free technique of tangential flow filtration (TFF) to a Creighton colloid of spherical AgNPs and specifically tailoring their size-distribution, concentration, and purity. First, a large batch of Creighton AgNPs (1-100 nm in diameter) were size-selected (20 nm and 12 nm in average diameter), concentrated, and purified via a three-step TFF procedure and characterized for effectiveness as SERS substrates in pre-resonance, resonance, and single-molecule resonance conditions for a Raman reporter, rhodamine 6G. The 20 nm AgNPs were found to have the highest surface enhancement factors (SEFs) in pre-resonance and single molecule resonance (SEFS of 2.1 x 10^6 and 2.5 x 10^10), while the 12 nm AgNPs yielded the highest SEFs in resonant conditions (2.0 x 10^6). The TFF procedure was then introduced to a diverse class of undergraduate and graduate students in an Experimental Nanomaterials and Nanoscience course to demonstrate the versatility of the proposed method for both gold nanoparticles and AgNPs, as well as the ease of applicability for use in different research disciplines and settings. Lastly, the 20 nm TFF-obtained AgNPs were employed for the sub-nanomolar biochemical detection of a potent apoptotic metabolite, chelerythrine (CET), in human lens epithelial cell extracts. The TFF-fractionated AgNP colloid allowed for quantification of CET content within several cell compartments via a reproducible calibration curve extending over five orders of magnitude (10^-5 to 10^-10 M in CET concentration). The results of these aims offer strong evidence that TFF can be 1) utilized to yield SERS substrates capable of extending detection limits and increasing spectral signals, 2) easily adapted for a variety of nanoparticle colloids as well as research and industrial settings, and 3) employed to obtain AgNPs that facilitate trace biochemical SERS-based detection even in extensive biological matrices.

Download or read book Metal Nanoparticles and Clusters written by Francis Leonard Deepak and published by Springer. This book was released on 2017-11-17 with total page 431 pages. Available in PDF, EPUB and Kindle. Book excerpt: ​This book covers the continually expanding field of metal nanoparticles and clusters, in particular their size-dependent properties and quantum phenomena. The approaches to the organization of atoms that form clusters and nanoparticles have been advancing rapidly in recent times. These advancements are described through a combination of experimental and computational approaches and are covered in detail by the authors. Recent highlights of the various emerging properties and applications ranging from plasmonics to catalysis are showcased.

Download or read book Surface Enhanced Raman Scattering written by Zhong-Qun Tian and published by John Wiley & Sons Incorporated. This book was released on 2010-06-14 with total page 400 pages. Available in PDF, EPUB and Kindle. Book excerpt: Surface-Enhanced Raman Spectroscopy: Principles, Experiments, and Applications is a comprehensive, up to date, and balanced treatment of the theoretical and practical aspects of Surface-Enhanced Raman Scattering (SERS), a useful branch of spectroscopy for several areas of science. This book describes the basic principles of SERS, including SERS mechanisms, performing SERS measurements, and interpreting data. Also emphasized are applications in electrochemistry; catalysis; surface processing and corrosion; Self-Assemble-Layer and L-B Films; polymer science; biology; medicine and drug analysis; sensors; fuel cells; forensics; and archaeology. It is an essential guide for student and professional analytical chemists.

Download or read book Surface Enhanced Raman Spectroscopy written by Sebastian Schlücker and published by John Wiley & Sons. This book was released on 2011-09-19 with total page 97 pages. Available in PDF, EPUB and Kindle. Book excerpt: Covering everything from the basic theoretical and practical knowledge to new exciting developments in the field with a focus on analytical and life science applications, this monograph shows how to apply surface-enhanced Raman scattering (SERS) for solving real world problems. From the contents: * Theory and practice of SERS * Analytical applications * SERS combined with other analytical techniques * Biophysical applications * Life science applications including various microscopies Aimed at analytical, surface and medicinal chemists, spectroscopists, biophysicists and materials scientists. Includes a Foreword by the renowned Raman spectroscopist Professor Wolfgang Kiefer, the former Editor-in-Chief of the Journal of Raman Spectroscopy.

Download or read book Determining the Electronic Properties of Surface Enhanced Raman Spectroscopy Substrates written by Liam David Whelan and published by . This book was released on 2015 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Surface Enhanced Raman Spectroscopy (SERS) is an ultra-sensitive technique for optical detection of target analytes. Our work focuses on detecting oil in water using SERS, with this thesis using phenanthrene as a model compound. SERS is a technique which takes advantage of the optical properties of metal substrates to greatly increase the intensities of adsorbed analytes' vibrational modes. The rapid development of novel materials as SERS active substrates requires an efficient screening method. SERS Enhancement Factor (EF) does correlate somewhat with surface morphology and UV-Vis absorption, however we present a technique which shows an even stronger correlation and is ultimately a better screening tool: Kelvin Probe Force Microscopy (KPFM). This technique maps the electronic properties of a substrate to its surface morphology. This thesis covers two classes of SERS substrates: annealed bimetallic systems and nanosphere patterned mono- and bimetallic systems. The ability to directly map the electronic properties of a substrate to its morphological properties is of critical importance in determining a key link between the macroscale SERS sensor response and the microscale substrate structure. Our major findings indicate that when Au/Cr nanostructured films' work function is near the calculated and experimental values for the HOMO-LUMO gap of the target analyte, phenanthrene, the observed SERS intensity reaches a maximum.

Download or read book Principles of Surface Enhanced Raman Spectroscopy written by Eric Le Ru and published by Elsevier. This book was released on 2008-11-17 with total page 688 pages. Available in PDF, EPUB and Kindle. Book excerpt: SERS was discovered in the 1970s and has since grown enormously in breadth, depth, and understanding. One of the major characteristics of SERS is its interdisciplinary nature: it lies at the boundary between physics, chemistry, colloid science, plasmonics, nanotechnology, and biology. By their very nature, it is impossible to find a textbook that will summarize the principles needed for SERS of these rather dissimilar and disconnected topics. Although a basic understanding of these topics is necessary for research projects in SERS with all its many aspects and applications, they are seldom touched upon as a coherent unit during most undergraduate studies in physics or chemistry. This book intends to fill this existing gap in the literature. It provides an overview of the underlying principles of SERS, from the fundamental understanding of the effect to its potential applications. It is aimed primarily at newcomers to the field, graduate students, researchers or scientists, attracted by the many applications of SERS and plasmonics or its basic science. The emphasis is on concepts and background material for SERS, such as Raman spectroscopy, the physics of plasmons, or colloid science, all of them introduced within the context of SERS, and from where the more specialized literature can be followed. Represents one of very few books fully dedicated to the topic of surface-enhanced Raman spectroscopy (SERS) Gives a comprehensive summary of the underlying physical concepts around SERS Provides a detailed analysis of plasmons and plasmonics

Download or read book Surface Enhanced Raman Scattering written by Richard Chang and published by Springer Science & Business Media. This book was released on 2013-11-11 with total page 424 pages. Available in PDF, EPUB and Kindle. Book excerpt: In the course of the development of surface science, advances have been identified with the introduction of new diagnostic probes for analytical characterization of the adsorbates and microscopic structure of surfaces and interfaces. Among the most recently de veloped techniques, and one around which a storm of controversy has developed, is what has now been earmarked as surface enhanced Raman scattering (SERS). Within this phenomenon, molecules adsorbed onto metal surfaces under certain conditions exhibit an anomalously large interaction cross section for the Raman effect. This makes it possible to observe the detailed vibrational signature of the adsorbate in the ambient phase with an energy resolution much higher than that which is presently available in electron energy loss spectroscopy and when the surface is in contact with a much larger amount of material than that which can be tolerated in infrared absorption experiments. The ability to perform vibrational spectroscopy under these conditions would lead to a new understanding about the chemical identity, geome try, and bonding of adsorbed material at a level previously unacces sible. It is for these reasons that the last few years have brought an explosion of activity surrounding the exploitation of SERS. The search for the origines) of the anomalous enhancement has given rise to a research sub-activity of its own. Efforts to explain the en hancement have led to an increased understanding of the whole range of phenomena associated with the interaction of photons with adsor bates and metal surfaces.