Raman-Activated, Interactive Sorting of Isotope-Labeled Bacteria.

Due to its high spatial resolution, Raman microspectroscopy allows for the analysis of single microbial cells. Since Raman spectroscopy analyzes the whole cell content, this method is phenotypic and can therefore be used to evaluate cellular changes. In particular, labeling with stable isotopes (SIPs) enables the versatile use and observation of different metabolic states in microbes.

Schwertmannite formation at cell junctions by a new filament-forming Fe(II)-oxidizing isolate affiliated with the novel genus Acidithrix.

A new acidophilic iron-oxidizing strain (C25) belonging to the novel genus Acidithrix was isolated from pelagic iron-rich aggregates ('iron snow') collected below the redoxcline of an acidic lignite mine lake. Strain C25 catalysed the oxidation of ferrous iron [Fe(II)] under oxic conditions at 25 °C at a rate of 3.8 mM Fe(II) day(-1) in synthetic medium and 3.

Elemental analysis-aided Raman spectroscopic studies on Chinese cloisonné wares and painted enamels from the Imperial Palace.

Two kinds of enamels, including Chinese cloisonné wares from Fuwang chamber and gourd-shaped painted enamels decorations from the Forbidden City, in the Imperial Palace of China, are investigated by micro-Raman spectroscopy in combination with laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) and energy-dispersive X-ray fluorescence (EDXRF) in order to examine and analyze the composition of the glaze layer in each case. In this study the excitation is employed with either a NIR laser (785 nm) or a red laser (632.8 nm) in order to effectively eliminate the interference of background fluorescence and resonance effect.

Raman imaging with a fiber-coupled multichannel spectrograph.

Until now, spatially resolved Raman Spectroscopy has required to scan a sample under investigation in a time-consuming step-by-step procedure. Here, we present a technique that allows the capture of an entire Raman image with only one single exposure. The Raman scattering arising from the sample was collected with a fiber-coupled high-performance astronomy spectrograph.

Raman investigations of Upper Cretaceous phosphorite and black shale from Safaga District, Red Sea, Egypt.

The mineral composition of the Upper Cretaceous Duwi phosphorite deposits and underlying Quseir Variegated Shale from Safaga district, Red Sea Range, Egypt, was investigated by dispersive and Fourier transformed Raman spectroscopy. The only phosphorous containing mineral detected in the phosphorite deposits was carbonate fluorapatite. Often carbonate fluorapatite appears associated with calcium sulfate and seldom with calcium carbonate in the investigated samples.

Evaluation of Colloids and Activation Agents for Determination of Melamine Using UV-SERS.

UV-SERS measurements offer a great potential for environmental or food (detection of food contaminats) analytics. Here, the UV-SERS enhancement potential of various kinds of metal colloids, such as Pd, Pt, Au, Ag, Au-Ag core-shell, and Ag-Au core-shell with different shapes and sizes, were studied using melamine as a test molecule. The influence of different activation (KF, KCl, KBr, K(2)SO(4)) agents onto the SERS activity of the nanomaterials was investigated, showing that the combination of a particular nanoparticle with a special activation agent is extremely crucial for the observed SERS enhancement.

Temperature-dependent Raman study of the smectic to nematic phase transition and vibrational analysis using density functional theory of the liquid crystalline system 4-decyloxy benzoic acid.

Room-temperature Raman spectra of the thermotropic liquid crystalline system, 4-decyloxy benzoic acid (4DBA) have been recorded and the experimentally observed bands are assigned by density functional theory (DFT) for the first time. The C-O and C-C stretching and C-H in-plane bending modes of the phenyl ring and C=O stretching modes of the -COOH group are the marker bands for the smectic (S) --> nematic (N) and nematic (N) --> isotropic (I) transitions for this system. The temperature-dependent Raman spectra for these bands in the heating cycle clearly characterize the S-->N and the N-->I transition over a range <1 degree C, which is much better than the earlier range of 23 degrees C for S-->N and 26 degrees C for the N-->I transition.

Three-dimensional molecular mapping of a multiple emulsion by means of CARS microscopy.

Multiple emulsions consisting of water droplets dispersed in an oil phase containing emulsifier which is emulsified in an outer water phase (W/O/W) are of great interest in pharmacology for developing new drugs, in the nutrition sciences for designing functional food, and in biology as model systems for cell organelles such as liposomes. In the food industry multiple emulsions with high sugar content in the aqueous phase can be used for the production of sweets, because the high sugar content prevents deterioration. However, for these emulsions the refractive indexes of oil and aqueous phase are very similar.

UV Raman spectroscopy--a technique for biological and mineralogical in situ planetary studies.

We report on the great advantages of using deep UV Raman system for in situ planetary applications. Among them are to be mentioned: (I) higher scattering efficiency compared to VIS-IR Raman excitation wavelengths, (II) electronic resonance effects which increase the intrinsically weak Raman signal thus improving the S/N ratio of the detected Raman signals and (III) spectral separation of Raman and fluorescence signals. All these advantages are making UV Raman a valuable technique for in situ planetary applications.

UV Raman imaging--a promising tool for astrobiology: comparative Raman studies with different excitation wavelengths on SNC Martian meteorites.

The great capabilities of UV Raman imaging have been demonstrated on the three Martian meteorites: Sayh al Uhaymir, Dar al Gani, and Zagami. Raman spectra without disturbing fluorescence and with high signal-to-noise-ratios and full of spectral features were derived. This result is of utmost importance for the development of powerful instruments for space missions.