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Micro-Raman spectroscopy is widely used for non-invasive tissue diagnosis and detection, as it provides detailed information about biomolecular composition, structure, and interaction of tissue. In this work, micro-Raman spectroscopy was used to investigate non-cancerous and cancerous nasopharyngeal tissues. The obtained nasopharyngeal tissue samples in vitro are divided into two groups: cancerous (n=12, undifferentiated non-keratinizing carcinomas) and non-cancerous (n=10, 7 chronic inflammations, 2 lymphomas and 1 lymphocytosis). Firstly, we analyzed the Raman spectra in the fingerprint (FP, 400-1800cm-1) region acquired. Preliminary results showed that there are some spectral differences in different pathological conditions. Furthermore, Raman spectra from cancerous and non-cancerous nasopharyngeal tissue in the high wavenumber region (HW, 2800-3100cm-1) were also reported for the first time. After detailed analysis, we achieved significant differences in Raman bands at 2854, 2874, 2934, and 3067cm-1 between cancerous and non-cancerous nasopharyngeal tissues. This study demonstrates that both fingerprint and high wavenumber regions of micro-Raman spectroscopy have the potential for the early detection of nasopharyngeal carcinomas.

Raman spectroscopy is a promising tool for detection of virus infection in live cells. In the present study, we demonstrate its feasibility to observe dynamic reaction of the live cell infected by virus. The Raman spectra of the adenovirus infected live cell (293 HEK) are analyzed by comparing with those of control cells. Principal component analysis (PCA) is employed also to analyze the spectra in detail. A band at 1650 cm-1 increases its intensity in the spectra measured at 24 hours after the virus infection. The infection of the virus is also examined by immune-staining and transmission electron microscope (TEM), and the virus infection is confirmed with these method also. It should be noted that the present technique does not require specifying the type of virus in advance.

A small, computer-controller drawdown bar device for coating glass-slide size substrates with thin films was designed and constructed. A variety of thin films of DNA-CTMA were fabricated. The results of electrical characterization and micro-Raman spectroscopy studies are reported.

Grodziec collection of stained glass panels consists of fourteen objects depicting figures of saints. Probably they belong to one, uniform set from the one of Lower Silesia churches. Recently eight of them, already after conservatory treatment, are exhibited in Jagiellonian University Museum of Collegium Maius in Krakow, while remaining six, which will be restored in nearest future, are stored in the National Museum in Wroclaw. This paper presents the results of the investigation of composition and corrosion products of glass from three panels of Wroclaw group. Since comparative analysis of historic glass composition is vital for its dating, to obtain the possibly full set of composition data with particular stress on light elements identification, the multi technique approach was necessary. The physicochemical analysis was carried out by X-ray fluorescence (XRF), micro-Raman spectroscopy and scanning electron microscopy with energy dispersive X-ray spectrometer (SEM/EDX). The study revealed that some of stained glasses have composition characteristic of northern medieval glass (potash-lime-silicate) while other pieces could be dated on 16th or 19th century. This confirms the suggestion from the former historic and scientific investigation of Krakow's set that the Wroclaw panels may be of the same medieval origin as the Krakow's ones and that they were already restored, at least in 19th c. The possibility of working on the whole set of panels from the Grodziec collection opens up the opportunity for conducting exceptional scientific study which will lead to the definitive designation of the provenance of this important collection, its history and age.

Confocal resonance Raman (RR) spectra were collected from single proliferating cells and analyzed to detect spectral patterns that are cell-cycle dependent, as a consequence of cellular proliferation — normal or abnormal. The cells’ biochemical age at each time point was confirmed by immunohistochemical staining to identify the presence or absence of cellular components that appear and/or disappear as the cells proceed through the cell-cycle. The RR spectra were collected and compared for each time point as the cells proceeded through the cell cycle to determine what spectral vibrational patterns are cell-cycle dependent. In this study, the question is whether the cell-cycle dependent RR spectral patterns of the vibrational modes observed in proliferating normal and neoplastic single cells are due to a state of cancer or are simply the consequences of the cells’ changing internal biochemistry due to the process of cellular proliferation --- normal or abnormal.

Growth in the percentage of male infertility has caused extensive concerns. The fast and reliable method is urgently required for diagnosis of semen samples. In our study, micro-Raman spectroscopy was employed to characterize and differentiate the normal and abnormal semen samples based on the differences of their specific Raman spectra which originated from biochemical components. Our preliminary results demonstrate that micro-Raman spectroscopy combined with multivariate analysis methods has the potential of being used to detect and differentiate semen samples.

Advanced optical instruments are useful for analysis and manipulation of individual living cells and their internal structures. We have employed Raman microspectroscopic analysis for assessment of algal lipid body (LB) volume in vivo. Some algae contain β-carotene in high amounts in their LBs, including strains which are considered useful in biotechnology for lipid and pigment production. We have detected proportionality between the Raman vibrations of β-carotene and the LB volume. This finding may allow fast acquisition of LB volume approximation valuable e.g. for Raman microspectroscopy assisted cell sorting. We combine optical manipulation and analysis on a microfluidic platform in order to achieve fast, effective, and non-invasive sorting based on spectroscopic features of the individual living cells. The resultant apparatus could find its use in demanding biotechnological applications such as selection of rare natural mutants or artificially modified cells resulting from genetic manipulations.

An "in vitro" study of Raman spectra from oral human tissues is reported in order to the develop a diagnostic method suitable for "in vivo" oral pathology follow-up. The investigated pathology is Pemphigus Vulgaris (PV) for which new techniques for guiding and monitoring therapy would be particularly useful. Raman spectra were obtained in the wavenumber regions from 1000 to 1800 cm -1 and 2700 to 3200 cm -1 from tissues from patients at different stages of pathology (active PV, under therapy and in PV remission stage) as confirmed by histopathological and immunofluorescence analysis. Differences in the spectra depending on tissue illness stage arise in 1150-1250 cm -1 (amide III) and 1420-1450 cm -1 (CH 3 deformation) regions and around 1650 cm -1 (amide I) and 2930 cm -1 (CH 3 symmetric stretch). A wavelet deconvolution procedure was applied to the spectra for better discriminating among the three different stages of illness and a linear regression analysis was used to fully exploit the content of information of Raman spectra.

Biophotonics is a new and highly interdisciplinary scientific discipline comprising the application of light (i.e. innovative photonic tools) in life sciences. It is non exaggerated to say Biophotonics is on the way to solve the most important problems in biomedicine. In particular Raman microspectroscopy allows one to derive detailed and specific information on a molecular level which other photonic methods methods can only provide by a limited extent. Here we will present latest results of our own research dealing with the application and development of innovative Raman spectroscopic techniques for biomedical applications.

In this work, fast and reliable spectroscopic methods in combination with chemometric tools were developed for simultaneous determination of Acetylsalicylic Acid, Acetaminophen and Caffeine in commercial formulations. For the first-order multivariate calibration method (PLS-1), calibration and validation sets were constructed with 23 and 10 samples respectively according to a central composite design. The Micro-Raman, FTIR-HATR and UV absorption spectra in the region of 100-2000 cm -1 , 400-4400 cm -1 and 200-350 nm, respectively, were recorded. The % REP's (Percentage of relative error of prediction) was less than 18 for all used spectroscopic techniques. Subsequently, commercial pharmaceutical samples were analyzed with percentage of recovery between 90 and 117% for the three compounds.

We report the results of scanning micro-Raman spectroscopy obtained on Au-Ag nanowires for a variety of chemical warfare agent simulants. Rough silver segments embedded in gold nanowires showed enhancement of 105 - 107 and allowed unique identification of 3 of 4 chemical agent simulants tested. These results suggest a promising method for detection of compounds significant for security applications, leading to sensors that are compact and selective.

Nonlinear Raman microspectroscopy is a powerful tool for minimally invasive chemical analysis of cells and tissues. In this report we evaluate the state-of-the-art of this technology with an eye on potential clinical applications.

Nonlinear Raman microspectroscopy is a promising advanced spectroscopic technique capable of providing chemically specific information completely noninvasively. Signal collected from a microscopic volume can be acquired at a rate significantly exceeding the one for conventional Raman scattering imaging. In this report we analyze the current limitations from the point of view of the signal-to-noise optimization and propose several solutions to outstanding technical problems.

The importance of sensitive monitoring of changes in Raman spectra in particular for microelectronic applications is discussed here. We explore the practicality of using a data-scattering method to analyse Raman spectra, and to establish the dependence of changes observed in all the spectral function characteristics on the parameters of data-scatter such as scatter closeness and scatter radii using "Trace Miner" software. In addition to the analysis performed on model data, analysis on experimental Raman data is also discussed. The sensitivity of the approach is fully appreciated.

Raman spectroscopy has been employed to measure the varying concentrations of two oral bacteria in simple mixtures. Evaporated droplets of centrifuged mixtures of Streptococcus sanguis and Streptococcus mutans were analyzed via Raman microspectroscopy. The concentration of s. sanguis was determined based upon the measured Raman spectrum, using partial least squares cross-validation, with an r2 value of 0.98.

Micro-Raman spectroscopy is an important molecular spectroscopic technique for the non-destructive examination of objects of art. In this work, Raman spectra of a number of Azo-pigments are presented, which are important artists' pigments in contemporary artifacts. The Azo-pigments, being a group of cheap pigments with good painting properties, form an important subgroup of pigments that became available to the artists at the end of the 19th and the beginning of the 20th century. A classification for these Azo-pigments is presented, which is based on their chemical properties, reflected in their molecular Raman spectrum. It is shown that a close spectral examination can help in assigning the unknown pigment to a class of pigments and thus assist in the identification of the painting material.

The applicability of Raman scattering for the study of intact chromosomes and constituting compounds, such as DNA and its bases, has been investigated, using normal Raman and Surface Enhanced Raman microspectroscopy.