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Silver particles, predominantly with the size of 40–80 nm, were immersion deposited onto porous silicon to form substrates appropriate for the detection of organic molecules by surface‐enhanced Raman scattering technique. These substrates have been demonstrated for the first time to provide detection of phospholipid molecules represented by dipalmitoylphosphatidylcholine at concentrations as low as 10−12 M when a 532 nm laser wavelength is used and 10−11 M at 633 nm wavelength. Label‐free detection is realized at these conditions.

Surface-enhanced Raman spectroscopy (SERS) is a promising optical method for analyzing molecular samples of various nature. Most SERS studies are of an applied nature indicating a serious potential for their application in analytical practice. Dendrite-like nanostructures have great potential for SERS, but the lack of a method for their predictable production significantly limits their implementation. In this paper, a method for controllable obtaining spatially

Serial crystallography at last generation X-ray synchrotron sources and free electron lasers enabled data collection with micrometer and even submicrometer size crystals, which have resulted in amazing progress in structural biology. However, imaging of small crystals, which although is highly demanded, remains a challenge, especially in the case of membrane protein crystals. Here we describe a new extremely sensitive method of the imaging of protein crystals that is based on coherent anti-Stokes Raman scattering.

Phone: þ375 17 292 23 60Here we report the SERS spectroscopy study of the herring sperm DNA adsorbed on the silvered porous silicon. Porous silicon has been fabricated by an electrochemical anodic etching of a highly doped n-type silicon wafer. It has been shown that the following silver immersion deposition on porous silicon lead to the formation of a layer of silver nano-and microparticles assembled in a quasi-ordered array. Reflectance spectroscopy has revealed that the silver layer demonstrates the surface plasmon resonance band expanded to near-IR range. Preliminary SERS measurements with rhodamine 6G have showed that the silvered porous silicon is characterized by a very good reproducibility of the SERS signal and one-year shelf life. It has been found that the silvered porous silicon is SERSactive in relation to the herring sperm DNA under the excitation at 473, 633 and 785 nm. Collection of the SERS spectra of the DNA molecules in the random points of the silvered porous silicon has resulted in their weak reproducibility typical for the solid SERS substrates. However, the SERS mapping has helped to find the classical DNA spectra. In addition, the herring sperm DNA at an extremely low concentration of 1 mg mL À1 has been detected with the SERS substrate based on the silvered porous silicon.

The present study was aimed at revealing the influence of the mechanical stress induced by water molecule adsorption on the composition of crystalline phases in the ZrO2 + 3 mol% Y2O3-nanoparticles. Three basic methods were used to determine the phase transition: neutron diffraction, Raman microspectroscopic scanning, and X-ray diffraction. The fact of reversible phase-structural β → α transformation and the simultaneous presence of two polymorphic structural modifications (β is the phase of the tetragonal syngony and α of monoclinic syngony in nanosized particles (9 nm)) under normal physical conditions was established by these methods. An assumption was made regarding the connection of the physical mechanism of transformation of the extremely nonequilibrium surface of nanoparticles with electronic exchange of the material of the near-surface layer of nanoparticles with the adsorption layer through donor–acceptor interaction. The principal possibility of creating direct-acting hydroelectric converters based on nanoscale YSZ (Yttria-Stabilized Zirconia) systems due to the reversible character of the considered effect was shown.

T HE DEVELOPMENT of modern bio-nanoelectronic technologies requires new hybrid organo-inorganic systems that have a specific functional purpose and allow work in the tissues of living organisms. The practical realization and scientific study of a hybrid twocomponent system in the form of DNA molecule fragments and nanoparticles of biocompatible ceramics was the goal of this work. The interaction of a DNA molecule with nanoparticles of a solid solution of the composition ZrO 2-3mol% Y 2 O 3 (YSZ) was studied using Raman scattering and transmission electron microscopy. Samples of YSZ oxide and hydroxide were investigated in triplicate at room temperature using LabRAM HR Evolution Horiba spectrometer and JEM 200A instrument. The effect of the force field of the surface of YSZ nanoparticles on the optical properties of the DNA molecule in the TRIS buffer solution was shown. The effects of increasing the intensity of spectral lines in the long-wavelength region 250-660 cm-1 (254 cm-1 , 322 cm-1 , 470 cm-1 , 663 cm-1). suppressing the intensity of spectral lines in the shortwave region 600-3300 cm-1 (604 cm-1 , 917 cm-1 , 951 cm-1 , 1256 cm-1 , 1302 cm-1 , 2767 cm-1 , 3180 cm-1 , 3241 cm-1 , 3285 cm-1), as well as shifting lines 519 cm-1 , 917 cm-1 , 1048 cm-1 , 1547 cm-1 and 1639 on 40-60 cm-1 in the shortwave region are established. From the standpoint of the theory of wave processes, a qualitative description of the detected Up-conversion effect was done. An assumption about the potential applicability of the YSZ nanoparticle surface-DNA nucleotide interfaces as a heterodyne frequency converter in molecular-and bio-electronic devices was made. Keywords: DNA in the electric field, immobilization of DNA molecules on the surface of semiconductors and dielectrics, Raman scattering, frequency modulation, heterodyne transfer of a frequency band, molecular electronics, bio-electronic, powder nanotechnologies.

The present study was aimed at revealing the influence of the mechanical stress induced by water molecules adsorption on the composition of crystalline phases in the ZrO2–3mol%Y2O3-nanoparticles. Three basic methods have been used to determine the phase transition: neutron diffraction, Raman microspectroscopic scanning, and X-ray diffraction. The fact of phase-structural β → α transformation and the simultaneous presence of two polymorphic structural modifications (β is the phase of the tetragonal syngony and α of monoclinic syngony in nanosized particles (9nm)) under normal physical conditions was established by these methods. Satisfactory consistency was achieved between the results obtained using different techniques.