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FTIR Study of Multifunctional Coatings

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EN
Nanoparticles of hydroxyapatite (HAp) or tricalcium phosphates (TCP) connected with fibrous phase create biomimetic system between the natural fibrous and ceramic materials building a bone. Chemical bonding between the implant and host tissue takes place through the phosphate layer, which is created on the bioactive implant surface when in contact with the body fluids environment. The Fourier transform infrared spectroscopy can yield microstructural information on the segment level complementary to the morphological information acquired from X-ray scattering as well as electron microscopy. The Fourier transform infrared method is applied to study thin films on different substrates. Moreover, the Fourier transform infrared microscope technique allows to obtain surface and cross-section maps in reflection and transmission modes. This leads to visualization of chemical imaging between substrates and films. In this work, the coatings with different addition of nanohydroxyapatite were deposited by electrodeposition method on titanium and Ti6Al4V alloys. Additionally, sublayers, such as TiO_2, were used to increase hydroxyapatite coating adhesion. The selection of suspension composition, depositing time and layer heat treatment conditions have the conclusive influence on the films parameters. All these experimental parameters were monitored during the sample preparation procedure. Changes in phase composition of biomaterials were determined by the Fourier transform infrared reflection technique based on focal plane array detection system. It has been found that results obtained by the Fourier transform infrared spectroscopy show the differences between the studied samples as well as that optimum time of HAp deposition was 90 s.
EN
Vibrational spectroscopy has been extensively used for in vitro and in vivo investigations of degradation mechanism and kinetics of different biomedical materials as well as it has been used to characterize the crystalline and amorphous domains in bio-mineralization process. Infrared and Raman spectroscopy methods are valuable tools in the biomaterials engineering allowing to study processes occurring during their preparation. In vitro tests, where the materials are immersed in simulated body fluids and/or artificial saliva, were used to evaluate the biocompatibility of biomaterials. This kind of tests are a wide range of repeatable and reproducible methods, which are regulated by international standards for commercial use and scientific development of new materials and products. The aim of this work was to examine phase composition of materials applied in dentistry. The bioactivity of such biomaterials was studied by immersing the samples in synthetic body fluid and artificial saliva. The changes were determined by the Fourier transform infrared and Raman microspectroscopy as well as scanning electron microscopy. It was found that results obtained by vibrational spectroscopy show the differences between the studied samples. Chemical reactions occurring during incubation of cements in artificial saliva as well as in synthetic body fluid result in formation of phosphates which deposit on the cement surface.
EN
In this study, the Fourier-transform infrared absorption and the Raman spectroscopies for analysis of corrosion products formed on the Fe and Cu metal surfaces after deposition in the chloride containing solution, were used. The obtained spectral patterns show that main constituent species of the corrosion products for Fe metal sample is lepidocrocite, while in the case of Cu surface there is formed mainly paratacamite. The obtained results confirm that application of vibrational spectroscopic methods is precise tool for identification and analysis of the corrosion products.
EN
The single cell gel electrophoresis method, known as comet assay, is a rapid and sensitive technique for testing novel chemicals and nanoparticles for genotoxicity, monitoring environmental contamination with genotoxins and human biomonitoring. In our studies we check the applicability of this method for the evaluation of biocompatibility of modified (MWNF) and non-modified multi-walled carbon nanotubes (MWNT) as well as potential genotoxicity of mercury(II) nitrate. The obtained results enabled us to conclude that the presence of Hg(NO₃)₂ (p<0.001) and MWNT (p<0.04) cause a significantly higher level of DNA damage in comparison to functionalised nanomaterials MWNF. It was implied that for the three investigated agents only mercury significantly enhanced genotoxic effect of X-ray exposure (p<0.001) and inhibition of radio-induced DNA damage repair. On the contrary, the presence of MWNF have no influence on cellular repair efficiencies, while incubation with MWNT causes apoptosis and consequently results in lack of attached cells. In conclusion, our results confirmed the genotoxicity of mercury and non-modified carbon nanotubes as well as the biocompatibility of modified nanotubes. Additionally, we proved the usefulness of comet method for the evaluation of genotoxicity and DNA repair under the influence of different compounds and nanomaterials.
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Analysis of Human Lenses by Raman Microspectroscopy

76%
EN
A cataract is an opacity (clouding) of the normally clear lens which develops as a result of aging, metabolic disorders, trauma or heredity. The number of patients with cataract is increasing exponentially. This disease requires surgical intervention, to remove the cloudy lens and to introduce the eye lens polymer. In this work we will present analyses of degraded parts of human lens. Experimental materials were obtained from the lens removed during surgical intervention. These biological samples were measured using Almega XR Confocal Raman spectrometer (Thermo Scientific) with an excitation source of 785 nm laser line. The Raman vibrations in the spectral region of 650-1750 cm¯¹ were analyzed. The difference spectra revealed an excess of tryptophan, tyrosine, phenylalanine, β-sheet conformation, and molecules or molecular groups.
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EN
Carbon nanoforms due to their unique properties can be applied in many areas also in medicine. This article presents preliminary genotoxicity studies of electrospun carbon nanofibers (ECNF). This material, apart from its numerous applications, may also be a candidate for use in medical therapy and diagnostics. Polyacrylonitrile (PAN) nanofibers received in the electrospinning process were carbonized and thereafter subjected to oxidation treatment (ECNF-F). Both types of fibres were analyzed with regard to genotoxic influence on the fibroblast line cells using comet assay. Additionally, comet assay experiments were conducted on biocompatible carbon nanotubes with a hydrophilic surface. The results indicate the key role of the oxidation process in the functionalization of carbon nanoparticles intended for medical purposes.
EN
The infrared spectromicroscopy is a quite recent technique rapidly developing thanks to the availability of new instruments and new brilliant synchrotron radiation sources in different areas and in particular to biomedical researches. In order to achieve a diffraction limited spatial resolution in tissue samples, we performed experiments at SINBAD, the synchrotron infrared beamline of the Laboratori Nazionali di Frascati. We characterized the chemical composition of prostate tissue samples taken from patients affected by prostate cancer disease. Different sizes of the pinholes were considered for the measurements. In the case of prostate tissue sections the results show the possibility to determine the intensity ratio of the CH_2 and CH_3 bands set at 2930 cm^{-1} and 2960 cm^{-1}, respectively. Experiments were also performed with a pinhole of 5 μm of diameter and the differences in both histological and chemical compositions of such samples were determined.
EN
Preliminary studies on the sediments collected from water meters of Krakow water supply system were performed in the cooperation with the Municipal Water Supply and Sewage. Creation and deposition of sediments on the measuring devices installed in the water supply system is a serious technological and economical problem for water companies, defectively operating for this reason water meters must be replaced. It is evident that knowledge of the chemical and phase composition of sediments is an important step towards resolving the problem of impurities in water supply systems. Four different samples of sediments, coming from water meters, were investigated using the proton-induced X-ray emission, the X-ray diffraction, the Fourier transform infrared and Raman spectroscopy. The X-ray methods revealed presence of amorphous and fine-crystalline phases as well as high content of iron-based compounds. As a crystalline phase, the most frequently appeared: goethite, lepidocrocite, iron oxides (hematite, maghemite, magnetite), calcium carbonate, and quartz. In one of the samples, the nanocrystalline phase was found and identified as hydrous iron oxyhydroxide ferrihydrite. Vibrational spectroscopy methods confirmed the composition of crystalline phases as well as enabled to estimate the abundance of amorphous phase in samples.
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