In this study, gold nanoparticles (AuNPs) were synthesised using green chemistry to decorate multi-walled carbon nanotubes (MWCNTs) made from walnut shells transmission electron microscopy, field-emission scanning electron microscopy (FESEM), atomic force microscopy and fourier transforms infrared spectroscopy were used to diagnose MWCNTs and AuNPs. MWCNT-COOAu, MWCNT-COO and MWCNT-Au were diagnosed by Raman, energy dispersive X-ray analysis and FESEM. The effect of AuNPs, MWCNT-COO, MWCNT-COOAu and MWCNT-Au on pure and serum alkaline phosphatase (ALP) enzyme activity was studied in vitro using the enzyme-substrate 4-nitrophenyl disodium orthophosphate. For pure enzymes, Vmax slightly increased as the concentration of MWCNT-Au, MWCNT-COOAu and MWCNTCOO increased, whereas the Vmax values decreased as the concentration of AuNPs increased. The inhibition type for all NPs varied. For serum ALP enzyme, the Vmax values for Au-based NPs decreased as the concentration of NPs increased. The Vmax values exceeded the standard value at the concentrations of 25, 50 and 75 ppm for MWCNT-Au and MWCNT-COOAu, whereas the Vmax values increased over the standard value for all concentrations of AuNPs.

Due to the globalization of food supply have been growing, there have been a great demands for food safety and quality assuarance for on-site detection. On-site detetction isuue is the process should be fast, simple, user-friendly and require minimal equipments. Herein, we developed a Radial chromatography (RC) biosensor integrated with the immuno-gold nanoparticles-coated magnetic nanoparticle (AuNPs@Fe3O4) for specific separation and detection of the target bacteria, E. coli O157:H7, in sample. The immuno-AuNPs@Fe3O4 specifically binds to E.coli O157:H7 creating AuNP@Fe3O4-E.coli complexes and captured bacteria were concentrated by magnet. The complex can be identified with inner ring derived from the difference of mobility of free AuNPs@Fe3O4 on the RC sensor. Our results show that AuNPs@Fe3O4 based RC sensor has high sensitivity to the target bacteria over non-target bacteria with a detection limit of 103 CFU/ml. Our system offers a rapid and sensitive means of detecting E.coli O157:H7 with naked eyes, which can be applied to the field diagnosis.

In this study, we synthesize silica-core gold-satellite nanoparticles (SGNPs) for the surface-enhanced Raman scattering (SERS) based sensing applications. They consist of gold satellite nanoparticles (AuNPs) fixed on the silica core nanoparticles, which sizes of AuNPs can be tunned by varying the amount of reactants (growth solution and reducing agent). Their surface plasmon resonance (SPR) properties were characterized by using UV-vis spectroscopy, showing that the growth of AuNPs on silica cores leads to the light absorption in the longer wavelength region. Furthermore, the size increase of AuNPs exhibited the dramatic change in SERS activity due to the formation of hot spots. The optimized SGNPs showing enhancement factor ~3.8x106 exhibited a detection limit of rhodamine 6G (R6G) as low as 10-8M. These findings suggest the importance of size control of SGNPs and their SPR properties to develop highly efficient SERS sensors.

We demonstrated size control of Au nanoparticles by heat treatment and their use as a catalyst for single-walled carbon nanotube (SWNTs) growth with narrow size distribution. We used uniformly sized Au nanoparticles from commercial Au colloid, and intentionally decreased their size through heat treatment at 800 oC under atmospheric Ar ambient. ST-cut quartz wafers were used as growth substrates to achieve parallel alignment of the SWNTs and to investigate the size relationship between Au nanoparticles and SWNTs. After the SWNTs were grown via chemical vapor deposition using methane gas, it was found that a high degree of horizontal alignment can be obtained when the particle density is low enough to produce individual SWNTs. The diameter of the Au nanoparticles gradually decreased from 3.8 to 2.9 nm, and the mean diameter of the SWNTs also changed from 1.6 to 1.2 nm for without and 60 min heat treatment, respectively. Raman results reconfirmed that the prolonged heat treatment of nanoparticles yields thinner tubes with narrower size distribution. This work demonstrated that heat treatment can be a straightforward and reliable method to control the size of catalytic nanoparticles and SWNT diameter.

Two dimensional (2D) arrays of noble metal nanoparticles are widely used in the sensing of nanoscale biological and chemical events. Research in this area has sparked considerable interest in many fields owing to the novel optical properties, e.g., the localized surface plasmon resonance, of these metallic nanoarrays. In this paper, we report successes in fabricating 2D arrays of gold nano-islands using nanosphere lithography. The reproducibility and the effectiveness of the nano-patterning method are tested by means of spin coating and capillary force deposition. We found that the capillary force deposition method was more effective for nanospheres with diameters greater than 600 nm, whereas the spin coating method works better for nanospheres with diameters less than 600 nm. The optimal deposition parameters for both methods were reported, showing about 80% reproducibility. In addition, we characterize gold nano-island arrays both geometrically with AFM as well as optically with UV-VIS spectrometry. The AFM images revealed that the obtained nano-arrays formed a hexagonal pattern of truncated tetrahedron nano-islands. The experimental and theoretical values of the geometric parameters were compared. The 2D gold nano-arrays showed strong LSPR in the absorption spectra. As the nano-islands increased in size, the LSPR absorption bands became red-shifted. Linear dependence of the plasmon absorption maximum on the size of the gold nano-islands was identified through the increment in the plasmon absorption maximum rate for a one nanometer increase in the characteristic length of the nano-islands. We found that the 2D gold nano-arrays showed nearly seven-fold higher sensitivity of the absorption spectrum to the size of the nano-islands as compared to colloidal gold nano-particles.

Aqueous gold nanoparticle dispersion was synthesized by chemical reduction method using diethanolamine as reducing agent and polyethyleneimine as dispersion stabilizer. The synthesis conditions for the stable dispersion of the gold nanoparticle suspension were determined by changing the amount of the reducing agent and dispersant during the wet chemical synthesis procedures. The face centered cubic lattice structure of the gold nanoparticles was confirmed by using X-ray diffraction and the morphologies of the nanoparticles were observed by transmission electron microscope. The synthesized gold nanoparticle dispersion was concentrated by evaporating the dispersion medium at room temperature followed by the addition of ethyleneglycol as humectant for the increase of the elastic properties to obtain gold nanoparticle inks for direct ink writing process. The line patterns were obtained with the gold nanoparticle inks during the writing procedures and the morphologies of the fine patterns were observed by scanning electron microscope.

신생혈관 형성은 세포의 성장 및 상처 치유 과정에서 중요한 현상이다. 그러나 성장인자의 불균형은 시각 및 면역질환과 같은 다양한 질환을 야기한다. 이러한 질환을 치료하는 방법 중 신생혈관 형성을 억제하는 것이 중요한 방법 중 하나이다. AuNPs의 기능과 기전이 신생혈관 형성에 있어서 아직 밝혀진 바가 없다. 현재 PEDF가 항신생혈관 형성 물질로 제안되고 있다. 본 연구에서 우리는 AuNPs가 BRECs에서 VEGF로 유도된 세포의 증식 및 이동, 신

본 연구는 BRECs에서 AGEs로 유도된 세포의 이동 및 침윤에 있어서 AuNP의 역할에 관한 연구이다. 소 망막으로부터 내피세포를 분리하고, 세포 생존율은 MTT assay로 확인하였다. Wound migration assay는 BRECs의 이동력을 확인하기 위해 수행하였다. Tube formation은 on-gel system을 통해 확인하였다. AuNP의 apoptosis 유도는 caspase-3 assay를 통해 확인하였다. AGE-BSA은 세

Background : Anemarrhena asphodeloides has efficacy such as anti-fungal, anti-cancerous, anti-inflammatory, anti-diabetic, Anti-UV etc. Metal nanoparticles are used for photo imaging, cancer resection and drug delivery etc in medical field. Therefore A. asphodeloides nanoparticles will be expected better efficacy for therapeutic properties in medical field. Methods and Results : The water extract of A. asphodeloides mediated the synthesis of Aa-AgNPs and Aa-AuNPs. Their characterized by several physicochemical techniques such as UV-Vis spectrophotometry, FE-TEM, EDX spectroscopy, SAED pattern, DLS size analysis, XRD analysis, and FTIR analysis. Both Aa-Ag/AuNPs were evaluated for cytotoxicity towards 3T3-L1, A549, HT29 and MCF7. Aa-AgNPs and Aa-Au NPs were found to be spherical, face-centered cubic nanocrystals with hydrodynamic diameter of 190 and 258 ㎚. In vitro cytotoxic analysis revealed that up to 50 ㎍/㎖-1 concentration Aa-Au NPs did not exhibit any toxicity on 3T3-L1, HT29 and MCF7 cell lines, while being specifically cytotoxic to A549 cell line. On the contrary, Aa-Ag NPs displayed a significantly higher toxicity in all cell lines specially MCF7 cell line. ROS generation was not affected by Aa-Au NPs, but Aa-AgNPs has a higher potential to induce oxidative stress in A549 cells than HT29 and MCF7 cells. Aa-Au NPs have the potential for anticancer agent during lung cancer treatment. Aa-AgNPs is also exhibited to inhibit cell migration by induce oxidatie stress. Conclusion : The Aa-Au/AgNPs might have the anticancer potential and might be effective in the lung cancer therapy, however further evaluation is must needed.

Green synthesis of gold nanoparticles(GNPs) considered more ecofriendly and cost effective than other chemical methods use of dangerous reagents and solvents, improved material and energy efficiency and enhanced design of non-toxic products. In this study, we developed a green synthesis method for using Caulis in Taeniam (BCT). BCT were characterized by UV-vis, Zetasizer, TEM, XRD, and FTIR. The antioxidant activity of BCT was determined by DPPH and ABTS radical-scavenging assays, and heme oxygenase-1 induction in RAW 264.7 macrophages. The resulting BCT appeared spherical with an average diameter of 67.171.39 nm The aAntioxidant activity was increased in a dependent manner. To conclude, the green synthesis of BCT-GNPs was successful, and it appers to be useful in the for future applications.