Synchrotron radiation in Novosibirsk: The first 13 years

We describe the development of activity at the Siberian Center for Synchrotron and Terahertz Radiation at Budker Institute of Nuclear Physics (BINP), SB RAS, since 1974, when the history of experiments with synchrotron radiation (SR) in the world was just beginning–there were no dedicated sources of radiation and works can be carried out at several nuclear centers in the world. BINP made a significant contribution to the development of synchrotron radiation sources, and SB RAS institutes did their part for development of SR application to problems of chemistry, catalysis, biology, geology and materials science. The experiments were made at VEPP-3/VEPP-4 installation.     

A first step towards practical single cell proteomics: a microfluidic antibody capture chip with TIRF detection

We have developed a generic platform to undertake the analysis of protein copy number from single cells. The approach described here is 'all-optical' whereby single cells are manipulated into separate analysis chambers using an optical trap; single cells are lysed by a shock wave caused by laser-induced microcavitation, and the protein released from a single cell is measured by total internal reflection microscopy as it is bound to micro-printed antibody spots within the device. The platform was tested using GFP transfected cells and the relative precision of the measurement method was determined to be 88%. Single cell measurements were also made on a breast cancer cell line to measure the relative levels of unlabelled human tumour suppressor protein p53 using a chip incorporating an antibody sandwich assay format. These results suggest that this is a viable method for measuring relative protein levels in single cells.     

Synchrotron radiation phase-contrast X-ray CT imaging of acupuncture points

Three-dimensional (3D) topographic structures of acupuncture points were investigated by using synchrotron radiation in-line X-ray phase contrast computerized tomography. Two acupuncture points, named Zhongji (RN3) and Zusanli (ST36), were studied. We found an accumulation of microvessels at each acupuncture point region. Images of the tissues surrounding the acupuncture points do not show such kinds of structure. This is the first time that 3D images have revealed the specific structures of acupuncture points.     

Soccer-playing metal oxide giant spheres: a first step towards patterning structurally well defined nano-object collectives

In context with the challenge to assemble giant molecules into patterns with limited size, molybdenum oxide giant spheres (with a molecular mass of about 16 kDa) could be 'kicked out' like soccer balls into the gas phase using matrix assisted laser desorption and ionization (MALDI) and detected by TOF mass spectrometry while cluster collectives ranging from dimers to pentamers were observed.     

同步辐射红外光谱技术在生物医用领域的应用

同步辐射作为一种新型红外光源,具有光谱宽、亮度高、分辨率高的特性,在生命科学领域具有广泛的应用。随着同步红外显微镜成像技术的不断发展,同步辐射红外光谱技术可以在原位探测亚细胞级别的生物化学变化,并保留细胞的生命特征。通过对蛋白质、核酸、磷脂等成分的定性和定量分析,可以了解骨细胞、神经细胞的病变,癌变细胞的活动情况以及植物细胞的营养状况等。同时,同步辐射红外光谱技术的应用范围正在不断扩展,其在药物释放的检测和生物化学过程的监控等方面也具有相当的应用前景。此外,在生物分子的分子间振动能级所处的远红外区,同步辐射红外光谱相比于常规红外光谱具有较高的信噪比。     

Unravelling ionization and fragmentation pathways of carotenoids using orbitrap technology: a first step towards identification of unknowns

Vegetables are a major source of carotenoids and carotenoids are identified as potentially important natural antioxidants that may aid in the prevention of several human chronic degenerative diseases. Characterization of carotenoids in organic biological matrices is a crucial step in any research valorization trajectory. This study reports for the first time the use of high mass resolution and exact mass orbitrap technology for the elucidation of carotenoid fragmentation pathways. This contributes to the generation of new tools for identifying unknown carotenoids based on fragmentation patterns. Two different chromatographic methods making use of different mobile phases resulted in the generation of different ion species because of the large influence of the mobile phase solvent composition on ionization. It was shown that depending on the molecular ion species that are generated (protonated ions or radical molecular ions), different fragments are formed when applying higher energy collisional dissociation. Fragmentation and the abundance of fragments provide valuable structural information on the type of functional groups, the polyene backbone and the location of double bonds in ring structures of carotenoids. Furthermore, coherence between specific substructures in the molecules and characteristic fragmentation patterns was observed allowing the assignment of fragmentation patterns for carotenoid substructures that can theoretically be extrapolated to carotenoids with similar (sub)structures. Differentiation between isomeric carotenoids by compound specific fragments could however not be made for all the isomeric groups under study. As a wide variety of isomeric forms of carotenoids exist in nature, the combination of good chromatographic separation with high resolution mass spectrometry and other complementary qualitative structure elucidation techniques such as a photo diode array detector and/or nuclear magnetic resonance spectroscopy are indispensable for unambiguous identification of unknown carotenoids. Copyright © 2013 John Wiley & Sons, Ltd.     

Use of synchrotron-radiation-based FTIR imaging for characterizing changes in cell contents

FTIR imaging of individual cells is still limited by the low signal-to-noise ratio obtained from analysis of such weakly absorbing organic matter when using a Globar IR source. In this study, we used FTIR imaging with a synchrotron radiation source and a focal plane array detector to determine changes in the cellular contents of cryofixed cells after culture for 48 h on Si(3)N(4) substrate. Several spectral differences were observed for cells deprived of glucose compared with control cells: a lower amide I-to-amide II ratio (P < 0.01); a different secondary structure profile of proteins (obtained from amide I spectral region curve fitting), with a significant increase in non-ordered structure components (P < 0.01); and a higher ν(C = C-H)/ν(as)(CH(3)) absorption ratio (P < 0.01), suggesting increased unsaturation of fatty acyl chains. Therefore, our study has shown that FTIR imaging with a synchrotron radiation source enables determination of several spectral changes of individual cells between two experimental conditions, which thus opens the way to cell biology studies with this vibrational spectroscopy technique.     

Synchrotron radiation excited X-ray fluorescence analysis using a graphite monochromator

Summary X-ray fluorescence analysis with monochromatic synchrotron radiation enables the direct analysis even of samples with a very strong matrix, while other methods require already a chemical pretreatment or preconcentration step. Because of free tunable excitation energy special elements or element groups of interest can be selectively excitated. The use of a graphite crystal for monochromatizing leads to a sufficient fluorescence intensity even for thin samples, because of a larger band width compared to other monochromator crystals. Nevertheless, a sufficient selectivity of the excitation will be achieved. Using a curved crystal focussing the beam in the horizontal plane of the storage ring, the intensity can be improved by a factor of about 20. The limits of detection for realistic samples (in this case aerosol samples are analysed) are in the range of 40 ng/ g. The results of the direct analysis of arsenic in aerosol samples are discussed and compared with an interlaboratory test.

---

Röntgenfluorescenzanalyse mit Synchrotronstrahlung unter Verwendung eines Graphitmonochromators

Zusammenfassung Röntgenfluorescenzanalyse mit monochromatisierter Synchrotronstrahlung erlaubt die Direktanalyse auch von stark matrixbeladenen Proben, bei denen bei anderen Methoden schon eine chemische Vorbehandlung oder Anreicherung notwendig wird. Die frei wählbare Monochromatorenergie erlaubt die selektive Anregung bestimmter Elemente oder Elementgruppen. Die Verwendung eines Graphitkristalls zur Monochromatisierung ergibt aufgrund der höheren Bandbreite gegenüber anderen Monochromatorkristallen auch bei dünnen Proben eine ausreichende Fluorescenzintensität bei gleichzeitig genügender Selektivität. Durch Verwendung eines gebogenen Graphitkristalls zur Fokussierung des Strahls in der horizontalen Ebene kann die Intensität noch einmal um den Faktor 20 gesteigert werden. Die Nachweisgrenzen von mit Aerosolen beaufschlagten Filtern liegen im Bereich von 40 ng/g. Die Ergebnisse der Analyse von Arsen in Aerosolproben werden diskutiert und mit den Ergebnissen einer Ringanalyse verglichen.

---

---

Dedicated to Prof. Dr. K. H. Lieser on the occasion of his 65th birthday     

In situ scanning FTIR microscopy and IR imaging of Pt electrode surface towards CO adsorption

In situ scanning FTIR microscopy was built up for the first time in the present work, which consists of an FTIR apparatus, an IR microscope, an X-Y mapping stage, and the specially designed electrochemical IR cell and computer software. It has been demonstrated that this new space-resolvdin situ IR technique can be used to study vibration properties of micro-area, and to perform IR imaging of electrode surface. The chemical image obtained using this technique for CO adsorption on Pt electrode illustrated, at a space-resolution of 10^-2 cm, the inhomogeneity and the distribu-tion of reactivity of micro-area of electrode surface. Project supported by the National Natural Science Foundation of China (Grant No. 29525307).     

In situ scanning FTIR microscopy and IR imaging of Pt electrode surface towards CO adsorption

In situ scanning FTIR microscopy was built up for the first time in the present work, which consists of an FTIR apparatus, an IR microscope, an X-Y mapping stage, and the specially designed electrochemical IR cell and computer software. It has been demonstrated that this new space-resolvd in situ IR technique can be used to study vibration properties of micro-area, and to perform IR imaging of electrode surface. The chemical image obtained using this technique fur CO adsorption on Pt electrode illustrated, at a space-resolution of 10~(-2) cm, the inhomogeneity and the distribution of reactivity of micro-area of electrode surface.     

A first step towards a quantum mechanical description of surface energy and diffusivity in the bubble model of positronium annihilation

In the bubble model of positronium annihilation in liquids, the inward contractile force on the bubble surface is described through classical surface tension of the liquids. In the present calculation, we adopted a simple quantum mechanical approach to describe the bubble surface energy in terms of the motion of a representative quasi-free electron outside the bubble. The bubble parameters (radius, potential, etc.) for different liquids obtained using the prescribed model are consistent with the results obtained using classical surface tension.     

Synchrotron FTIR spectroscopy of weak torsional bands: A case study of cis-methyl formate

The far infrared spectrum of cis-methyl formate has been recorded on the AILES beamline of the synchrotron SOLEIL using a Fourier transform infrared spectrometer coupled to a long path cell. The very weak fundamental band associated with the methyl-top torsion mode (ν(18)) was observed. The frequency analysis was performed using the "rho axis method", and the microwave and millimeter-wave data from the literature. A precise determination of the band origins (ν(18) (A) = 132.4303 cm(-1) and ν(18) (E) = 131.8445 cm(-1)) and of the barrier height [V(3) = 370.7398 (58) cm(-1)] have been obtained. The intensity of the ν(18) fundamental band was determined to be 3.4 × 10(-21) cm(-1)∕(molecule cm(-2)) at 297 K, equally shared among A-A and E-E transitions, thus leading to a dipole moment component μ(c) ((3)) equal to 0.0483 D. The results were compared with the ab initio calcula-tions of Senent et al. [Astrophys. J. 627, 567 (2005)].     

Natural products active against African trypanosomes: a step towards new drugs

This review covers compounds with activity on African trypanosomes (mainly Trypanosoma brucei subsp.,T congolense and T vivax) isolated from natural sources and is organized according to the structure of the etabolites (alkaloids, phenolic derivatives, quinones, terpenes and other metabolites). The literature from he mid-1980s up to June 2003 is reviewed and 89 references are cited.     

The first quantitative rating system of the antioxidant capacity of beauty creams via the Briggs-Rauscher reaction: a crucial step towards evidence-based cosmetics

Oxidative damage is the primary cause of skin aging. Skin care products are numerous and overwhelming, yet there is certain similarity among different formulations. Moisturizers are ubiquitous and the presence of particular added ingredients supports specific marketing claims. The antioxidant effects of botanical polyphenols possess tremendous marketing appeal, because oxidative stress is caused by an imbalance between the production of reactive oxygen species (ROS) and the skin ability to neutralize them. The concept of evidence-based cosmetics lacks a widely accepted method to estimate the antioxidant capacity of the beauty cream. This was the motive force of the present study: for the first time we put forth a quantitative rating system of skin care products. The overall antioxidant power of 75 widely used and advertised beauty creams was comparatively measured via the oscillating Briggs-Rauscher (BR) reaction. Many dermocosmetic products confirmed their ability to ensure protection against free radicals, even if differences among various creams are striking and often not correlated with the their price. The method we developed is simple and cheap and it can allow dermatologists and consumers to compare and choose effectively; on the other hand, producers can used this method to select the most active antioxidant cosmetic agent to optimise the product performance.     

Colored inks analysis and differentiation: a first step in artistic contemporary prints discrimination

Prints are the most popular artistic technique. Due to their manufacturing procedure, they are also one of the most frequently falsified types of artwork. In terms of their economic and historic value, the chemical analysis and characterisation of coloured inks and their principal constituent materials (pigments), together with the historical and aesthetic information available in the Catalogues Raisonées, are important tools in distinguishing originals from non-original prints.The chemical characterisation and discrimination of coloured inks has test in this study. Analysis using Fourier transform infrared spectroscopy (FTIR), Scanning electron microscopy (SEM) and X-ray diffraction (XRD) has been done on blue pigments and inks, due to this colour is one of the most representative for the presence of organic and inorganic materials in their composition. Conclusion obtained for this colour would demonstrate the capability of the approach when it is applied to any other coloured set of inks.     

Epitope mapping of allergen ovalbumin using biofunctionalized magnetic beads packed in microfluidic channels The first step towards epitope-based vaccines

Specific allergen immunotherapy is frequently associated with adverse reactions. Several strategies are being developed to reduce the allergenicity while maintaining the therapeutic benefits. Peptide immunotherapy is one such approach. Methods for the simple and rapid identification of immunogenic epitopes of allergens (i.e. allergenic epitopes) are ongoing and could potentially lead to peptide-based vaccines. An epitope extraction technique, based on biofunctionalized magnetic microspheres self-organized under a magnetic field in a channel of a simple microfluidic device fabricated from polydimethylsiloxane, was applied in the isolation and identification of prospective allergenic epitopes. Similarly to chromatographic column separations, the easily replaceable plug of self-organized beads in the channel benefits especially from an even larger surface-to-volume ratio and an enhanced interaction of the surfaces with passing samples. Ovalbumin, the major protein of egg white and a typical representative of food allergens, was selected as the model molecule. Highly resistant ovalbumin was at first efficiently digested by a magnetic proteolytic reactor with trypsin treated with l-1-tosylamido-2-phenylethyl chloromethyl ketone and the second step, i.e. capture of allergenic epitopes from the mixture of peptides, was performed by a magnetic immunoaffinity carrier with orientedly immobilized rabbit anti-ovalbumin IgG molecules. Captured peptides were released with 0.05% trifluoroacetic acid. The elution fractions were analyzed by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry. The peptide fragment of ovalbumin HIATNAVLFFGR (m/z: 1345.75, position: 371-382) was identified as a relevant allergenic epitope in this way. Such a microfluidic magnetic force-based epitope extraction technique applied in the epitope mapping of ovalbumin has the potential to be a significant step towards developing safe and cost-effective epitope-based vaccines.     

Immobilization of atrazine on gold,a first step towards the elaboration of an indirect immunosensor: characterization by XPS and PM‐IRRAS

As part of our long‐term goal to design a novel type of immunosensor based on IR transduction, we devised two strategies to immobilize derivatives of the herbicide atrazine on the surface of planar gold substrates. Both strategies take advantage of the well‐known formation of self‐assembled monolayers of thiolates via spontaneous chemisorption of thiols or disulphides on noble metal surfaces. The first strategy involved the direct chemisorption of a disulphide derivative of atrazine, while the second strategy was based on the covalent attachment of a polymer tethered with atrazine derivatives to a previously adsorbed thiolate carrying a carboxylic acid head group. The resulting organic thin films on gold were characterized by polarization modulation infrared reflection‐absorption spectroscopy (PM‐IRRAS) and XPS. The binding of a polyclonal anti‐atrazine antibody to both sensing layers was also tested and compared. It appeared that specific molecular recognition occurred only on the atrazine disulphide sensing layer. Copyright © 2006 John Wiley & Sons, Ltd.