Surface Enhanced Raman Spectroscopy (SERS) has demonstrated significant benefit in the identification of biological molecules. In this paper we have examined how to identify and differentiate the 150 kDa protein myeloperoxidase (MPO) from its corresponding antibody (Ab) and their immunocomplex through the use of SERS. The SERS signal of these biological molecules was enabled by 40 nm gold nanoparticles. The SERS spectra for both MPO and the Ab (an IgG molecule) demonstrated results consistent with previous published work on the Raman spectra of MPO and IgG antibodies. The immunocomplex SERS spectra showed peak shifts and intensity variations that could be attributed to conformational changes that occur during immunocomplex formation. Several key spectral areas have been identified which correspond to specific amino acids being shielded from undergoing resonance while new amino acid residues are made visible in the SERS spectrum of the immunocomplex and could be a result of conformational binding. These results indicate that SERS can be used to identify binding events and distinguish an immunocomplex from its individual components.

Elisabeth S. Papazoglou

Sundar Babu

David R. Hansberry

Sakya Mohapatra

Chirag Patel

SERS study on myeloperoxidase and its immunocomplex: Identification of binding interactions

Drop coating deposition Raman (DCDR) microspectroscopy was used to investigate interaction of the complexed cationic copper 5,10,15,20-tetrakis(1-methyl-4-pyridyl) porphyrin (CuP) and phosphorothioate analog of dT15 oligonucleotide with liposomes, the lipid composition of which imitated the natural plasmatic membrane. Great advantage of dried drops on DCDR plates over a solution sample is that the specific drying process on the special hydrophobic surface efficiently separates liposomes from small species in the solvent. In our case, liposomes with bound CuP/oligonucleotide complexes formed a ring at the edge part of the dried drop while dried solution of this complex remained inside this ring. High quality spectra measured from the ring by using Raman confocal microspectrometer revealed unperturbed arrangement of lipid chains by the drying process, partial binding of the CuP/oligonucleotide complexes to liposomes, and a certain reorientation of lipid chains as a consequence of this interaction.

E. Kocišová

M. Procházka

J. Štepánek

P. Mojzeš

Interaction of porphyrin/oligonucleotide complex with liposomes studied by drop coating deposition Raman spectroscopy

The effect of calcium, magnesium, strontium and barium ions on the electronic structure of m-nitrobenzoates was studied. The FT-IR spectra of m-nitrobenzoic acid and its salts were registered, assigned and analyzed. Characteristic shifts and changes in intensities of bands along the metal series were observed. The structures of m-nitrobenzoic acid and its calcium, magnesium, strontium and barium salts were optimized at the B3LYP/LANL2DZ level. Geometric aromaticity indices, atomic charges, dipole moments and energies were also calculated.

Mariola Samsonowicz

Molecular structure of calcium, magnesium, strontium and barium m-nitrobenzoates

Synthetic eumelanin produced using 5,6-dihydroxyindole-2-carboxylic acid as precursor and H2O2/horseradish peroxidase as oxidative reagent, in form of dry powder, has been investigated under photoexcitation by TR-EPR spectroscopy. The formation of spin polarized radical pairs from triplet excited states of melanin has been observed both in absence and in presence of oxygen and has been followed as a function of the temperature in the range 140–290 K. The triplet mechanism explains the observed polarization pattern in net emission. In the presence of oxygen new radical pairs are formed by interaction of melanin with molecular oxygen.

Fosca Conti

Lucia Panzella

Alessandra Napolitano

Marco d&#x1fbd;Ischia

Antonio Toffoletti

Time-resolved EPR investigation of oxygen and temperature effects on synthetic eumelanin

In the present contribution we present a new procedure for the Mean Square Displacement (MSD) determination from Elastic Incoherent Neutron Scattering (EINS) where the connection between the Self-Distribution Function (SDF) and the measured EINS intensity profile is highlighted. We show how the SDF procedure allows both the total and the partial MSD evaluation, through the total and the partial SDFs. The procedure is applied on EINS data collected, by the IN13 backscattering spectrometer (ILL, Grenoble), on aqueous mixtures of sucrose and trehalose.

Salvatore Magaz&#249;

Federica Migliardo

Antonio Benedetto

Miguel Gonzalez

Claudia Mondelli

Self-distribution-function procedure in elastic incoherent neutron scattering for biosystems molecular motion characterization

Investigations on the structure and function of biomolecules often depend on the availability of topological information to build up structural models or to characterize conformational changes during function. Electron paramagnetic resonance (EPR) spectroscopy in combination with site&#x2013;directed spin labeling (SDSL) allow to determine intra- and intermolecular distances in the range from 4&#x2013;70 &#xc5;, covering the range of interest for biomolecules. The approach does not require crystalline samples and is well suited also for molecules exhibiting intrinsic flexibility. This article is intended to give an overview on pulsed EPR in conjunction with SDSL to study protein interactions as well as conformational changes, exemplified on the tRNA modifying enzyme MnmE.

Sabine B&#xf6;hme

Heinz-J&#xfc;rgen Steinhoff

Johann P. Klare

Accessing the distance range of interest in biomolecules&#x3a; Site-directed spin labeling and DEER spectroscopy

In this work the effect of sodium(I), calcium(II), lanthanum(III) and thorium(IV) ions on the electronic structure of cinnamic acid (phenylacrylic acid) was studied. In this research: infrared (FT-IR), Raman (FT-Raman), nuclear magnetic resonance (1H, 13C NMR) were used. In the series of Na(I)→ Ca(II)→ La(III)→ Th(IV) cinnamates: (1) systematic shifts of several bands in the FT-IR and FT-Raman spectra, and (2) regular chemical shifts of protons 1H and 13C nuclei were observed.

M. Kalinowska

W. Lewandowski

R. Swislocka

E. Regulska

The FT-IR, FT-Raman, 1H and 13C NMR study on molecular structure of sodium(I), calcium(II), lanthanum(III) and thorium(IV) cinnamates

Structure and functioning of chromatin is determined by interactions of DNA with numerous nuclear proteins. The most abundant and yet not completely understood non-histone chromosomal proteins are those belonging to a High Mobility Group (HMG) namely HMGB1. The interplay of this protein on DNA with linker histone H1 and other proteins determines both structure and functioning of the chromatin. A combination of UV and IR absorption and circular dichroism (CD) spectroscopy was applied to investigate the structure and formation of large supramolecular DNA–protein complexes. This combination of techniques was used to overcome limitations of UV-CD (ECD) spectroscopy due to considerable light scattering in such solutions. Based on the analysis of FTIR and UV circular dichroism spectra and AFM imaging the interaction of DNA with high-mobility group non-histone chromatin protein HMGB1 and linker histone H1 was studied.

Alexander Polyanichko

Helmut Wieser

Structural organization of DNA–protein complexes of chromatin studied by vibrational and electronic circular dichroism

Our objective is to develop a simple monitoring technique for rapid, sensitive and quantitative drugs detection in body fluids, with no reagent added and no need for qualified professionals. The user-friendly automatic Fluo-imager will (a) measure the full-range 3D fluorescence map of the inserted fluid sample, (b) determine the chemical nature and concentration of the drugs and (c) transfer the results through internet to the diagnosis center. For these goals the fluorescence measurement data will be examined by neuronal network-pattern recognition software. The software identifies the chemical nature and the appropriate concentration of the drug by comparison of the obtained 3D pattern with the contents of the data bank. One of the problems in the approach under consideration is the high optical density of body fluids in the UV region, which raises difficulties in the fluorescence measurements. In this paper, we have attempted to overcome this problem by means of preliminary dilution. Nevertheless, the problem of subtraction of the fluid fluorescence background still needs to be addressed.

Natalia V. Strashnikova

Arcady P. Gershanik

Nona Papiashvili

Daniel Khankin

Rivka Cohen-Luria

Shlomo Mark

Yehoshua Kalisky

Abraham H. Parola

Towards instantaneous quantitative fluoroimaging drugs determination in body fluids with no added reagents

Two-dimensional electronic spectroscopy is a sensitive probe of solvation dynamics. Using a pump–probe geometry with a pulse shaper [Optics Express 15 (2007), 16681-16689; Optics Express 16 (2008), 17420-17428], we present temperature dependent 2D spectra of laser dyes dissolved in glass-forming solvents. At low waiting times, the system has not yet relaxed, resulting in a spectrum that is elongated along the diagonal. At longer times, the system loses its memory of the initial excitation frequency, and the 2D spectrum rounds out. As the temperature is lowered, the time scale of this relaxation grows, and the elongation persists for longer waiting times. This can be measured in the ratio of the diagonal width to the anti-diagonal width; the behavior of this ratio is representative of the frequency–frequency correlation function [Optics Letters 31 (2006), 3354–3356]. Near the glass transition temperature, the relaxation behavior changes. Understanding this change is important for interpreting temperature-dependent dynamics of biological systems.

K. L .M. Lewis

J. A. Myers

F. Fuller

P. F. Tekavec

J. P. Ogilvie

Two-dimensional electronic spectroscopy signatures of the glass transition

About this journal

Journal of Spectroscopy publishes research into the theory and application of spectroscopy across all disciplines, including biology, chemistry, engineering, earth sciences, medicine, materials science, physics, and space science.

Journal profile

Meet the editorial board

Chief Editor&nbsp;Dr Daniel Cozzolino&nbsp;is based at the University of Queensland, Australia. His research focuses on the developments of chemometric and spectroscopic methods for use in agriculture and food applications.

Editor spotlight

Submit your proposal

Do you think there is an emerging area of research that really needs to be highlighted? Or an existing research area that has been overlooked or would benefit from deeper investigation? Raise the profile of a research area by leading a Special Issue.

Special Issues

Author guidelines

Editorial board

Databases and indexing

title

Journal of Spectroscopy publishes research into the theory and application of spectroscopy across all disciplines, including biology, chemistry, engineering, earth sciences, medicine, materials science, physics, and space science.

description

https://images.hindawi.com/journals/jspec/jspec.banner.jpg

twitter:card

twitter:description

twitter:site

twitter:title

twitter:url

twitter:image

Journal of Spectroscopy | Hindawi

Journal of Spectroscopy

This Issue is now open for submissions.
Papers are published upon acceptance, regardless of the Special Issue publication date.

Call for papers

A. Cupane