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Real-time polymerase chain reaction (RT-PCR) Saliva biomarkers Tumor mixus (TM) Salivary gland tumor The paper concentrates on the role of saliva in the early diagnosis of salivary gland tumor. Due to the still not fully understood etiology of head and neck cancer, the fundamental objective of this study is to find tumor markers of salivary gland tumor progression. This work demonstrates the feasibility of Attenuated Total Reflection Fourier Transform Infrared spectroscopy (ATR-FTIR) to track spectral variations between saliva samples derived from healthy volunteers and from salivary gland tumor (tumor mixus, TM) patients. Furthermore, a Real-Time Polymerase Chain Reaction (RT-PCR) has been used to detect a selected genes expression associated with neoplasm changes. The obtained results imply that spectral signals attributed to the amide I/II (secondary structure of protein), carbohydrates and inorganic phosphates oscillations are the most sensitive to alterations associated with the salivary gland cancer progression. Several spectroscopic biomarkers have been indicated as potential predictors of salivary gland tumor development. Additionally, the RT-PCR results reveal the increased level of Bcl-2 factor in salivary gland tumor patients' samples which may be related to inhibition of apoptosis process and increasing uncontrolled cell proliferation. Such combination of physico-chemical methods is a unique approach towards better understanding the tumor's etiology and early diagnosis problem. Based on the promising findings presented in this article, it could be concluded that saliva fluid has a great potential to be used as a first-line diagnostic tool in patients with suspicion of salivary gland tumor.

This report describes the first detailed characterization of the molecular structure of Lu AA33810, a selective Y5 receptor antagonist, and its behavior at the solid/liquid interface after conjugation with gold nanoparticles (GNPs). Physicochemical characterization, including imaging by scanning electron microscopy as well as electrophoretic mobility and dynamic light scattering measurements, was performed to determine the morphology, electrokinetic properties and range of stability of the GNPs. A comprehensive vibrational analysis, employing Raman spectroscopy, Fourier transform infrared absorption, surface-enhanced Raman spectroscopy, and surface-enhanced infrared absorption methods, is reported. The experimental data are supported by density functional theory calculations. It is implied that the Thz and Phe rings determine the adsorption geometry of Lu AA33810 on the studied GNPs and adopt a tilted orientation, exposing the interaction between the Thz free electron pair and the metallic nanosubstrates. The analysis also provides evidence for strong interaction between the free electron pairs located on the oxygen atoms of the SO2 fragment of methanesulfonamide and the GNPs. The results provide important insight into designing new compounds with agonistic or antagonistic properties toward the Y5 receptor.

An investigation of a numismatic collection of silver denarii from the early Piast dynasty was conducted using Fourier-transform infrared spectroscopy. The studied coins, minted between 995 and 1020 AD under the rules of Boleslaus the Brave and Mieszko II Lambert, belong to the collection of the National Museum in Kraków. Fourier-transform infrared spectroscopy imaging and mapping have been used for recording a visual image of the surface chemistry based on vibrational spectra and accurately representing the distribution of chemical compounds, respectively. Additionally, scanning electron microscopy coupled to energy-dispersive X-ray analysis was used to study the surface topography of the coins and characterize their elemental composition. Differences in the distribution of the identified chemical compounds were detected in heterogeneous areas of the denarii. Corrosion effects, associated to many factors including the alloy composition, the metallographic structure, the manufacturing processes, and the environment were also observed and identified. KEYWORDSBoleslaus the Brave, Fourier-transform infrared spectroscopy, FT-IR, numismatic studies, scanning electron microscopy coupled to energy-dispersive X-ray analysis, SEM/EDX, silver coins 1 | INTRODUCTION Nowadays, due to the need for high sensitivity, reliability and nondestructiveness, several analytical methods are continuously been developed to study cultural heritage objects, including numismatic collections. Vibrational spectroscopy methods (infrared absorption spectroscopy and Raman spectroscopy), X-ray fluorescence (XRF), and ion beam analysis techniques (particle-induced X-ray emission [PIXE], particle-induced γ-ray emission, and Rutherford backscattering spectrometry) are the most commonly used in this area and allow for high sensitivity and reliable identification. [1][2][3][4][5][6][7][8][9][10][11][12][13][14][15] These kinds of studies are useful to enrich the discussion on many historical aspects, such as coinage production, provenance of raw materials, forgeries, and conservation treatments. [16][17][18][19][20] In the previously published paper, we have already described the voltammetry of immobilized particles study of a series of 20 denarii from Boleslaus the Brave and Mieszko II Lambert. 21 The analytical results can offer complementary information to archaeologists, art historians, and conservation professionals, interested in finding a correlation between the chemical composition of the coins and their historical, economical, and political aspects.Additionally, numismatic objects have a higher survival rate in comparison to other types of historic artifacts. Therefore, in the last few years there has been an increasing interest in the field of physicochemical analysis of historic coins. However, the analysis can be difficult because of chemical changes and corrosion processes caused by different human and natural factors, which noticeably alter the surface composition of the objects. 22,23 In a previous paper, 16 XRF analysis was performed...

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This work presents near-infrared Raman spectroscopy (FT-RS) and surface-enhanced Raman scattering (SERS) studies of three pyridine-α-hydroxymethyl biphenyl phosphine oxide isomers: (diphenylphosphoryl)(pyridin-2-yl)methanol (α-Py), (diphenylphosphoryl)(pyridin-3-yl)methanol (β-Py), and (diphenylphosphoryl)(pyridin-4-yl)methanol (γ-Py) adsorbed onto colloidal and roughened in oxidation-reduction cycles silver surfaces. The molecular geometries in the equilibrium state and vibrational frequencies were calculated by density functional theory (DFT) at the B3LYP 6-311G(df,p) level of theory. The results imply that the most stable structure of the investigated molecules is a dimer created by two intermolecular hydrogen bonds between the H atom of the α-hydroxyl group (in up (HOU) or down (HOD) stereo bonds position) and the O atom of tertiary phosphine oxide (═O) of the two monomers. Comparison the FT-RS spectra with the respective SERS spectra allowed us to predict the orientation of the hydroxyphosphonate derivatives of pyridine that depends upon both the position of the substituent relative to the ring N atom (in α-, β-, and γ-position, respectively) and the type of silver substrate.

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A novel approach of combining conventional infrared spectroscopy (IR) and atomic force microscopy (AFM) is presented to better understand the behavior of a drug adsorbed on a metal substrate at the nanoscale level. Tip-enhanced infrared nanospectroscopy (TEIRA) was used for the first time to investigate Lu AA33810, a selective brain-penetrating Y5 receptor antagonist, after immobilization on gold nanoparticles (GNPs). Here, a gold coated AFM tip and gold substrate were used to obtain the near-field electromagnetic field trapping effect. Because of the huge signal enhancement, it was possible to obtain the spectral information regarding the self-assembled monolayer of the investigated molecule. The effect of two orthogonal polarizations (p-and s-polarization modulations) of the excitation laser beam on the spectral patterns is also discussed. The results show that there is a strong relationship between the state of polarization of the incident radiation and the relative infrared band intensities. Another factor affecting the observed spectral differences is the topology of the metal substrate, which may result in the induction of a cross-polarization effect. The performed analysis indicates that the C-C bond from the cyclohexyl group is oriented almost parallel to the metal surface. Conversely, the p-and s-polarized spectral variations suggest that the O=S=O angle is high enough to enable the simultaneous interaction of both oxygen atoms with the GNPs.