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To investigate the expression of C-JNK, RANKL and OPG after SP600125 administration in cultured dental follicle cells (DFCs). TRAP staining and electron microscope were carried out on day 7 and 9 after coculture of BMMs and DFCs with a ratio of 5:1 in different groups. To determine the effects of SP600125 on the expression of C-JNK, RANKL and OPG mRNA and protein, cultured DFCs were divided into control group, DMSO group and SP600125 groups. Real-time PCR and Western blot analysis were performed to investigate the expression of the mRNA and protein, respectively. TRAP assay indicated that the number of multinucleated osteoclasts in the SP600125 group showed significant decrease compared with that of control (P

A solid-phase dendritic Ag nanostructure was synthesized in the presence of silk fibroin biomacromolecule and planted on the glass to form three-dimensional (3D) silvernanodendrite@glass film. When NO 3 - , Cl − and SO 4 2 - were added in the synthesis process of the film to study their influence on the Raman activity of this substrate using MB as probe molecule, it’s found that the substrate with Cl −1 gives the most intensive enhancement, and two ways were proposed to explain this phenomenon. Its superiority in practical application of surface-enhanced Raman scattering (SERS) was verified by analyzing the characteristic Raman spectrum of Sildenafil between 1150 cm −1 and 1699 cm −1 . Besides, the absorption mechanism of GSH on the film through the role of peptide bond was analyzed. GSH interacts strongly with the silver surface via the ν(C S) in two different conformers. The carboxyl and the amide groups are also involved in the adsorption process. In this experiment, we synthesized, studied and applied this as-growth substrate and found some information about its interaction with different molecular bonds and functional groups of peptide.

The paper further investigated the relationship between the modification of the surface chemistry and the enhancement mechanisms of borohydride-reduced silver particles (BRSC). The bands of residual ions die down while the anomalous bands increase gradually with the increasing of the concentration of Cl− and Br−. It means the residual ions are displaced gradually by the added Cl− or Br− and the two halides can lead to the aggregation of the BRSC to a certain extent. However, the most strongly binding anions – I−, cannot cause any aggregation of silver particles. From the detection of methylene blue (MB), the relationship between the modification of silver surface chemistry and the enhancement mechanisms was discussed. Chloride gives the greatest enhancement while the iodide gives the lowest enhancement among the different kinds of anions. There are also some anomalous bands in the SERS spectra of MB, and these anomalous bands were given rational explanation in this paper.

The surface enhanced Raman scattering (SERS) spectrum of methylene blue (MB) varies observably when using different kinds of silver colloids as SERS active substrates. The colloids were synthesized by three different methods. Sodium chloride, sodium sulfate, sodium nitrate were chosen as aggregating agents in this study. Three kinds of anions were performed on hydroxylamine-reduced silver colloid and the effect of the chloride anion was investigated in the three SERS-active colloids. From the results it can be concluded that the interaction between analyte and silver nanoparticles is different in different kinds of colloidal environments and the addition of anions also has a great influence on SERS spectrum. The effects on the SERS spectra were qualitatively explained through the study of SERS spectra for various silver colloids and aggregating agents in this paper.

The viability of the application of surface-enhanced Raman spectroscopy (SERS) to the semi-quantitative analysis of the triphenylmethane dye gentian violet was examined by using activated borohydride-reduced silver colloids. Raman and SERS spectra of aqueous solutions of gentian violet at different pH values were acquired for the first time and equally intense SERS signals were obtained at both acidic and alkaline pH values. Two maxima intensities observed in the pH profile revealed the presence of different ionization states of the dye. The pH conditions for SERS were optimized over the pH range 1 to 12 and the biggest enhancement for SERS of this charged dye was found to be at pH 2.0; thus, this condition was used for semi-quantitative analysis. A good linear correlation was observed for the dependence of the signal intensities of the SERS bands at 1620 cm−1 ( R = 0.999) and 1370 cm−1 ( R = 0.952) on dye concentration over the range 10−6 to 10−4 mol/L, using laser excitation at 514.5 nm. At concentrations of dye above 10−2 mol/L, the concentration dependence of the SERS signals is nonlinear. This is explained as due to the precipitation of metallic silver as well as due to saturation caused by complete coverage of the SERS substrate. A series of intensities of the band at 1620 cm−1 measured from dye molecules proved that the single-molecule limit of gentian violet is attained at the concentration of 10−9 mol/L.

Surface enhanced Raman scattering (SERS) is potentially tool in the characterization of biomolecules such as amino acids, complicated peptides and proteins, and even tissues or living cells. Amino acids and short peptides contain different functional groups. Therefore, they are suitable for the investigations of the competitive-interactions of these functional groups with colloidal silver surfaces. In this paper, Normal Raman and SERS of amino acids Leucine and Isoleucine and short peptide Leu-Leu were measured on the silver colloidal substrate. Raman shifts that stem from different vibrational mode in the molecular inner structure, and the variations of SERS of the samples were analyzed in this study. The results show that different connection of one methyl to the main chains of the isomer amino acids resulted in different vibration modes in the Normal Raman spectra of Leucine and Isoleucine. In the SERS spectra of the isomer amino acids, all frequency shifts are expressed more differently than those in Normal Raman spectra of solid state. Orientation of this isomer amino acids, as well as specific-competitive interactions of their functional groups with the colloidal silver surface, were speculated by detailed spectral analysis of the obtained SERS spectra. In addition, the dipeptide Leu-Leu, as the corresponding homodipeptide of Leucine, was also measured adsorbed on the colloidal silver surface. The SERS spectrum of Leu-Leu is different from its corresponding amino acid Leucine but both of them are adsorbed on the silver surface through the carboxylate moiety.

In Raman detection, the most popular solution for the samples is tri-distilled water. But the effect of aqueous solution is barely studied in Raman spectroscopy. In fact Raman spectroscopy of solid-state and liquid-state are obvious different. In addition, FWHM of Raman spectral peaks also change evidently. In this paper, several samples were selected for the experiment; including sodium nitrate, sodium nitrite, glucose and caffeine. By comparing the Raman spectroscopy of samples at different concentrations, it is found that the concentration of the sample can affect the strength of Raman spectroscopy, but it can hardly impact FWHM of Raman spectral peaks. By comparing the Raman spectroscopy of liquid-state with the Raman spectroscopy of solid-state, it is observed that the FWHM of some Raman spectral peaks varied obviously; that may be because when the sample was dissolved into the water, the crystal lattice structure was broken, and for some samples atom form became ion form in aqueous solution. Those structural variations caused the variation of the FWHM. The Raman spectroscopy of caffeine aqueous solution at very low concentration was also detected and analyzed. Compared with the Raman spectra of solid-state samples, it is found that some Raman spectral peaks disappeared when the sample was dissolved in water. It is possible that the low concentration of the sample result in the weakening of Raman signals and the disappearing of some weak Raman spectral peaks. Then Ag nanoparticles were added into the caffeine aqueous solution, the results suggest that surface enhanced Raman spectroscopy (SERS) not only can enhance the Raman spectral signal, but also can reduce the effect of aqueous solution. It is concluded that the concentration of sample only affects the strength of Raman spectroscopy; the aqueous solution can affect the FWHM of Raman spectral peaks; and SERS can reduce the effect of aqueous solution.

In this article, the relationship between the states of Ag core-Au shell (core-shell) nanoparticles (NP) and the intensity of Raman scattering of analytes dissolved in the water and adsorbed on the NP was studied. The core-shell NP were synthesised by coating Au layers over Ag seeds by the method of "seed-growth". To highlight the advantage of the core-shell NP, Ag colloid and Au colloid were chosen for contrasting. The analyte that were chosen for this testing were methylene blue (MB) for the reason that MB has very strong signal in surface-enhanced Raman scattering (SERS). The SERS activity of optimalizing states of Ag and Au colloids were compared with that of core-shell NP when MB was used as analyte. In this study, sodium chloride, sodium sulfate and sodium nitrate were used as aggregating agents for Ag, Au colloids and core-shell NP, because anions have a strong influence on the SERS efficiency and the stability of colloids. The results indicate that core-shell NP can obviously enhance the SERS of MB. The aim of this study is to prove that compared with the metal colloid, the core-shell NP is a high efficiency SERS active substrate.

Surface-Enhanced Raman scattering (SERS) are potentially important tools in the characterization of biomolecules such as amino acids, complicated peptides and proteins, and even tissues or living cells. Amino acids and small peptides contain different functional groups. Therefore, they are suitable for the investigations of the competitive-interactions of these functional groups with colloidal silver surfaces. SERS spectra of Phe and Gly-Gly are measured in colloidal silver solutions in this paper. Orientation of the samples, as well as specific-competitive interactions of their functional groups with the colloidal silver surface, were predicted by detailed spectral analysis of the obtained SERS spectra. In addition, using SERS measurement obtained in different time we discuss an existing controversy regarding the adsorption mechanism of Gly-Gly on the silver surface.

In this paper, Surface-enhanced Raman scattering (SERS) spectra of phenylalanine were studied for borohydride- reduced silver colloid using different aggregating agents, and the effects on SERS of aggregation on this colloid environments were analysed. The choice of aggregating agent greatly influences the aggregation of colloid and the surface-enhanced Raman spectroscopy of the analyte. Sodium chloride, sodium sulfate, sodium nitrate, potassium chloride and calcium chloride were used as aggregating agents. The results show that the surface- enhanced Raman spectroscopy of phenylalanine varies observably when different kinds and concentration of aggregating agents are used. Sodium chloride gave the most intense bands among the three kinds of sodium salts for phenylalanine with the borohydride-reduced silver colloid. It can be concluded that chloride ions are mainly responsible for the aggregation of nanoparticles in this silver colloid. Potassium chloride and calcium chloride were used as aggregating agents to contrast the effect of different cations in colloid silver. It was found that a new peak emerged and the intensity of SERS spectrum decreased when calcium chloride were used as aggregating agent. The results indicate that not only the anions but also the cations influence the SERS of analyte. Through the study of SERS spectra for phenylalanine with different kinds of aggregating agents, the application of SERS technique in the field of biochemistry may be expanded.

SERS spectroscopy was employed to study the interaction of the antitumoral drug paclitaxel with human serum albumin. The normal Raman spectrum of the paclitaxel was shown in this study for the first time. There were some differences existing in the surface-enhanced Raman scattering (SERS) spectrum of paclitaxel and its human serum albumin (HSA), which demonstrated that there was high bioaffinity of paclitaxel to human serum albumin. And it was also found that there existed some differences in the SERS of the paclitaxel/HSA complexes at different pH values, which may indicated some significant information on the binding site, by which paclitaxel binds to human serum albumin. It can provide significant instruction in the synthesis of the drug and in improving the therapeutic efficacy of this drug.

In the present paper, the surface enhanced Raman scattering (SERS) technique was employed to study the SERS spectra of biotin molecules formed on the silver surface. The adsorption geometries of biotin molecules on the silver surface were analyzed based on the SERS data. It can be found that most vibration modes show a Raman shift in silver sol after the addition of sodium chloride solution. In addition, The Raman signals of biotin become weaker and weaker with the increase of the concentration of sodium chloride. This may be due to that the interaction between chloride ions and silver particles is stronger than the interaction between biotin molecules and silver particles. When the concentration of sodium chloride in silver colloid is higher than 0.05mol/L, superfluous chloride ions may form an absorption layer so that biotin can not be adsorbed on silver surface directly. The changes in intensity and profile shape in the SERS spectra suggest different adsorption behavior and surface-coverage of biotin on silver surface. The SERS spectra of biotin suggest that the contribution of the charge transfer mechanism to SERS may be dominant.

In this study, surface-enhanced Raman scattering(SERS)spectra of vitamin E were obtained on colloidal silver(Ag). Alpha-(-) tocopherol which is the only form that is recognized to meet human requirements was selected to study. The analytes (±)- -tocopherol were dissolved in chloroform (CHCl3) and the silver colloid was poured into the compound. Silver colloid was reduced by hydroxylamine hydrochloride. The analytes were the supernatant after standing the mixture for the reason that chloroform have no signals in surface-enhanced Raman scattering in the Ag colloid, and it would not affect the determination of the (±)- -tocopherol. The Normal Raman and SERS spectrum of Vitamin E were contrastively studied to realize how the vitamin E stuck to the silver nanoparticles. The results show the fat-soluble substances can be analysed by SERS. The spectra indicate that the molecules are adsorbed on the surface through the COO- groups by the simultaneous involvement of a and -type coordination. These results suggest some important criteria for consideration in SERS measurements and also provide important insights into the problem of predicting SERS activities for different fat-soluble substances.