Five analogues of a novel group of boron derivatives of aminophosphonic acids-N-benzylamino-(3-boronphenyl)-S-methylphosphonic acid (m-PhS), N-benzylamino-(4-boronphenyl)-S-methylphosphonic acid (p-PhS), N-benzylamino-(2-boronphenyl)-R-methylphosphonic acid (o-PhR), N-benzylamino-(3-boronphenyl)-R-methylphosphonic acid (m-PhR), and N-benzylamino-(4-boronphenyl)-R-methylphosphonic acid (p-PhR)-were studied using Fourier transform infrared (FT IR), Fourier transform Raman (FT RS), and surface-enhanced Raman (SERS) spectroscopies. Analysis of obtained FT IR and FT RS spectra show that all investigated compounds in the solid state exist as dimeric species formed by an H-bonding interaction between -B(OH)(2) moieties of each monomer. In addition, comparison of the wavenumbers, intensities, and broadness of bands from the FT Raman and SERS spectra allowed information to be obtained regarding the adsorption geometry of the investigated compounds immobilized onto an electrochemically roughened silver substrate.

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This paper shows systematic spectroscopic studies using Fourier-transform infrared absorption (FT-IR), Fourier-transform Raman (FT-Raman), and surface-enhanced Raman (SERS) in an aqueous silver sol of fluoro and formyl analogues of phenylboronic acids: 2-fluorophenylboronic acid (2-F-PhB(OH)2), 3-fluorophenylboronic acid (3-F-PhB(OH)2), 4-fluorophenylboronic acid (4-F-PhB(OH)2), 2-formylphenylboronic acid (2-CHO-PhB(OH)2), 3-formylphenylboronic acid (3-CHO-PhB(OH)2), and 4-formylphenylboronic acid (4-CHO-PhB(OH)2). To produce an extensive table of vibrational spectra, density functional theory (DFT) calculations with the B3LYP method at the 6-311++G(d,p) level of theory were performed for the ground state geometry of the most stable species, dimers in cis-trans conformation. On the basis of the SERS spectral profile, the adsorption modes of the phenylboronic acid isomers were proposed. The type of substituent and its position in the phenyl ring have a strong influence on the geometry of isomers on the silver nanoparticle's surface. This effect was especially evident in the case of 4-CH-PhB(OH)2, for which dearomatization of the phenyl ring took place upon adsorption.

The application of metal nanoparticles as an efficient drug delivery system is one of the directions of cancer therapy development. However, this strategy requires precise information about how the drug interacts with the applied nanocarrier. In this study, atomic force microscopy combined with infrared spectroscopy (AFM-IR) was used for the first time to investigate the erlotinib adsorption structure on two different types of 15 nm metal nanoparticle mono-layers, namely, silver nanoparticle (AgNP) and gold nanoparticle (AuNP) mono-layers. Because the metal nanoparticles are loosely bound samples, only the tapping AFM-IR mode is suitable for the collection of IR maps and spectra for such a system. The obtained results indicated the relevance of the AFM-IR technique for characterizing drug interactions with a metal mono-layer surface. The investigated drug interacts with the AgNPs mainly through phenyl rings and methoxy moieties, while quinazoline, amino, and ethoxy moieties appear to be farther from the surface. For the AuNPs, the interaction occurs through both the phenyl ring and the quinazoline moiety. Additionally, the aliphatic groups of erlotinib directly participate in this interaction. The novelty of the present work is also related to the use of the tapping AFM-IR mode to study metal NP mono-layers with a drug adsorbed on them. The collected IR maps for the most enhanced erlotinib bands show specific areas with very high signal intensity. The connection between these areas and the "hot spots" typical for the surface plasmon resonance phenomenon of metals is considered. KEYWORDSmetal nanoparticle mono-layer, drug's adsorption, infrared nanospectroscopy, atomic force microscopy, erlotinib

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.

In this study, we present surface‐enhanced Raman spectroscopy (SERS) investigations for the erlotinib adsorbed onto silver nanoparticles (AgNPs). The observed spectral patterns, namely, changes in width and wavenumber of the SERS bands in comparison with these occurring in the corresponding Raman spectrum suggest how the investigated drug interacts with the applied metal nanoparticles. Moreover, the physicochemical investigations including transmission electron microscope, UV–Vis spectroscopy, and electrophoretic mobility measurements were used for characterization of the nanoparticles and erlotinib/nanoparticles stability. Briefly, the performed measurements suggest that the erlotinib strong interacts with the applied AgNPs. Additionally, the studied interaction seems to be the strongest for the acetylene moiety, which undergoes deprotonation. Also the –CNH and –OCH3 groups play an important role in the erlotinib–metal nanoparticles interaction. This is opposite for the CH2, which is only in certain distance from this nanosurface. In the case of the aromatic rings the two different ways of interaction were recognized. The phenyl ring interacts rather weak with the AgNPs and is oriented perpendicular onto the surface. Whereas, the quanizoline moiety only participates in this interaction with more or less tilted orientation with regards to the AgNPs. On the other hand, the SERS analysis for the different erlotinib concentration indicates that the discussed interaction is sensitive for the drug dilution.

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