We have developed biocompatible, photostable, and multiplexing-compatible surface-enhanced Raman spectroscopic tagging material (SERS dots) composed of silver nanoparticle-embedded silica spheres and organic Raman labels for cellular cancer targeting in living cells. SERS dots showed linear dependency of Raman signatures on their different amounts, allowing their possibility for the quantification of targets. In addition, the antibody-conjugated SERS dots were successfully applied to the targeting of HER2 and CD10 on cellular membranes and exhibited good specificity. SERS dots demonstrate the potential for high-throughput screening of biomolecules using vibrational information.

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We have developed multifunctional fluorescent surface enhanced Raman spectroscopic tagging material (F-SERS dots) composed of silver nanoparticle-embedded silica spheres with fluorescent organic dye and specific Raman labels for multiplex targeting, tracking, and imaging of cellular/molecular events in the living organism. In this study, F-SERS dots fabricated with specific target antibodies (BAX and BAD) were employed for the detection of apoptosis. The F-SERS dots did not show any particular toxicity in several cell lines. The F-SERS dots could monitor the apoptosis effectively and simultaneously through fluorescent images as well as Raman signals in both cells and tissues with high selectivity. Our results clearly demonstrate that F-SERS dots can be easily applicable to multiplex analysis of diverse cellular/molecular events important for maintaining cellular homeostasis.

In order to determine on the anti-complement activity of triterpenes, following eleven triterpenoides were isolated from the fruits of the Zizyphus jujuba MILL: ceanothane-type triterpenes: colubrinic acid (1), zizyberenalic acid (11); lupane-type triterpenes: alphitolic acid (2), 3-O-cis-p-coumaroyl alphitolic acid (3), 3-O-trans-pcoumaroyl alphitolic acid (4), betulinic acid (7), betulonic acid (9); and oleanane-type triterpenes: 3-O-cis-pcoumaroyl maslinic acid (5), 3-O-trans-p-coumaroyl maslinic acid (6), oleanolic acid (8), oleanonic acid (10). These compounds were examined for their anti-complement activity against the classical pathway of the complement system. Among them, compounds 5, 6, and 8 exhibited significant anti-complement activity with IC 50 values of 101.4, 143.9, and 163.4 m mM, respectively, whereas the ceanothane-type and the lupane-type triterpenes were inactive. This suggests that the oleanane-structure plays an important role in inhibiting the hemolytic activity of human serum against erythrocytes.

A new type of encoded bead, which uses surface-enhanced Raman scattering (SERS), is described for multiplex immunoassays. Silver nanoparticles were embedded in sulfonated polystyrene (PS) beads via a polyol method, and they were used as SERS-active substrates. Raman-label organic compounds such as 4-methylbenzenethiol (4-MT), 2-naphthalenethiol (2-NT), and benzenethiol (BT) were then adsorbed onto the silver nanoparticles in the sulfonated PS bead. Although only three kinds of encoding have been demonstrated here, various combinations of these Raman-label organic compounds have the potential to give a large number of tags. The Raman-label-incorporated particles were then coated with a silica shell using tetraethoxyorthosilicate (TEOS) for chemical stability and biocompatibility. The resulting beads showed unique and intense Raman signals for the labeled organic compounds. We demonstrated that SERS-encoded beads could be used for multiplex detection with a model using streptavidin and p53. In our system, the binding event of target molecules and the type of ligand can be simultaneously recognized by Raman spectroscopy using a single laser-line excitation (514.5 nm).

The MeOH extracts from approximately 200 Korean plants were investigated in an ongoing search for natural products with potent antioxidant activity. Among them, the MeOH extract of the rhizome of Dryopteris crassirhizoma NAKAI (Aspidiaceae) had a significant antioxidant effect on the 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging activity. D. crassirhizoma is a pteridophyte and its rhizome is a well known Chinese crude drug, which has been used clinically in Korea, Japan, and China as a vermicide. 1) In addition, phloroglucinol derivatives (albaspidin, aspidin, flavaspidic acids, and dryocrassin) and kaempferol acetyl rhamnosides (crassirhizomosides A-C and sutchuenoside A) have been isolated from this plant source previously. 2,3) The phloroglucinol derivatives possessed antibacterial, 4) antitumor promoting, 5) nitric oxide inhibitory, 6) and anti-reverse transcriptase activities. 7) More recently, we reported the antibacterial activity of the phloroglucinol derivatives from this plant. 8) However, the antioxidant activity of the phloroglucinol derivatives isolated from D. crassirhizoma has not been reported. The aim of this study was to evaluate the antioxidant activity of the compounds isolated from D. crassirhizoma. MATERIALS AND METHODSPlant Rhizome of Dryopteris crassirhizoma was collected in Mt. Sulak, Korea in July 2002 and identified by Prof. Ki-Hwan Bae, College of Pharmacy, Chungnam National University, Korea. A voucher specimen (CNU 1011) was deposited in the herbarium of the College of Pharmacy, Chungnam National University, Korea.Isolation of Flavaspidic Acids PB (1) and AB (2) The dried rhizome (1 kg) of D. crassirhizoma was extracted with MeOH (3 l, 48 hϫ2) at room temperature and the MeOH solution was then concentrated to dryness in vacuo to afford a dark brown syrupy residue (150 g). The MeOH extract was suspended in H 2 O (1 l) and then shaken with EtOAc (1 lϫ2). The EtOAc-soluble fraction (80 g) was subjected to column chromatography on silica gel and eluted with hexane (10% acetone) and increasing amount of acetone to 80% acetone. Eight fractions (each 1 l) were collected. These fractions were tested in DPPH radical scavenging assay in vitro as a model for antioxidant activity. The fractions 5 and 6 showed antioxidant activity. A combined fraction of fractions 5 and 6 (8 g) was subjected to column chromatography on Sephadex LH-20 using MeOH to afford two compounds: flavaspidic acid PB (1, 300 mg), and flavaspidic acid AB (2, 150 mg).Flavaspidic Acid PB (1 DPPH Radical Scavenging Activity DPPH radical scavenging activity was measured according to the procedure described by Takao et al. 9) Ten microliters of each sample, dissolved in DMSO, was prepared in a 96 well plate and then 190 ml of 200 mM ethanolic DPPH solution was added. The mixture was incubated at room temperature for 30 min and the absorbance of the reaction mixture was measured at 517 nm. DPPH radical scavenging activity (%) is expressed as follows:DPPH radical scavenging activity (%)ϭ(A control ϪA sample )/A control ϫ...

The medicinal and physicochemical properties of nanoscale materials are strong functions of the particle size and the materials used in their synthesis. The nanoparticle shape also contributes significantly to their medicinal properties. Several shapes ranging from oval, spherical, rods, to teardrop structures may be obtained by chemical methods. Triangular and hexagonal nanoparticles have been synthesized by using a pine cone extract (PCE). Here, we report the discovery that PCE, when reacted with silver nitrate ions, yields a high percentage of thin, flat, single-crystalline nanohexagonal and nanotriangular silver nanoparticles. The nanohexagonal and nanotriangular nanoparticles appear to grow by a process involving rapid reduction with assembly at room temperature at a high pH. The nanoparticles were characterized by UV–Vis absorption spectroscopy, SEM-EDS, TEM, FTIR, and X-ray diffraction analyses. The anisotropy of the nanoparticle shape results in large near-infrared absorption by the particles. Highly anisotropic particles are applicable in various fields, including agriculture and medicine. The obtained silver nanoparticles (Ag NPs) had significant antibacterial action on both Gram classes of bacteria associated with agriculture. Because the Ag NPs are encapsulated with functional group-rich PCE, they can be easily integrated in various applications.

Immunoassays using nanomaterials have been rapidly developed for the analysis of multiple biomolecules. Highly sensitive and biocompatible surface enhanced Raman spectroscopy-active nanomaterials have been used for biomolecule analysis by many research groups in order to overcome intrinsic problems of conventional immunoassays. We used fluorescent surface-enhanced Raman spectroscopic dots (F-SERS dots) to detect biomolecules in this study. The F-SERS dots are composed of silver nanoparticle-embedded silica nanospheres, organic Raman tagging materials, and fluorescent dyes. The F-SERS dots demonstrated highly sensitive, selective, and multifunctional characteristics for multiplex targeting, tracking, and imaging of cellular and molecular events in the living organism. We successfully applied F-SERS dots for the detection of three cellular proteins, including CD34, Sca-1, and SP-C. These proteins are simultaneously expressed in bronchioalveolar stem cells (BASCs) in the murine lung. We analyzed the relative expression ratios of each protein in BASCs since external standards were used to evaluate SERS intensity in tissue. Quantitative comparisons of multiple protein expression in tissue were first attempted using SERS-encoded nanoprobes. Our results suggested that immunoassays using F-SERS dots offered significant increases in sensitivity and selectivity. Such immunoassays may serve as the primary next-generation labeling technologies for the simultaneous analysis of multiple biomolecules.