An effective and inexpensive method is developed to fabricate periodic arrays by sacrificial colloidal monolayer template route by chemical deposition and further physical deposition. By a colloidal template induced precursor solution dipping strategy, different periodic arrays of semi-hollow sphere array, inverse opal with monolayer pore arrays and hole arrays are obtained under different conditions. After magnetron sputtering deposition, their morphologies are changed to novel micro/nanostructured arrays of honeycomb-shaped arrays, hollow cavity arrays, and regular network arrays due to multiple direction deposition of sputtering deposition and shadow effect. After coating a gold thin layer, these periodic micro/nanostructured arrays are used as SERS active substrates and demonstrate a very stable SERS performance compared with periodic arrays achieved by direct colloidal template-induced chemical deposition. Additionally, a honeycomb-shaped array displays better SERS enhancement than that of a hollow cavity array or a regular network array. After optimization of honeycomb-shaped arrays with different periodicities, an array with periodicity of 350 nm demonstrates much stronger SERS enhancement and possesses a low detection limit of 10(-11) M R6G. Such stable SERS performance is useful for practical application in portable Raman detecting devices to detect organic molecules.

Effects of nitrogen incorporation on the interface chemical bonding states, optical dielectric function, band alignment, and electrical properties of sputtering-derived HfTiO high-kgate dielectrics on GaAs substrates have been studied by angle resolved X-ray photoemission spectroscopy (ARXPS), spectroscopy ellipsometry (SE), and electrical measurements.

Their properties are usually dependent on morphologies and sizes, and hence the fabrication of controllable uniform micro/nanostructured arrays on a large-scale becomes more important. Conventional methods for obtaining periodical nanostructured arrays are lithographic techniques including laser lithography, [ 26,27 ] electron-beam lithography, [28][29][30] X-ray lithography, [ 31 ] atomic force microscope lithography, [ 32 ] scanning tunneling microscopy technology, [ 33 ] and so on. However, these techniques can not be afforded to most laboratories because of their high processing costs and lower production effi ciency. [ 34 ] In recent decades, with fast development of colloidal science and self-assembly technology, large-scaled monolayer colloidal crystals can be fabricated using highly monodispersed colloidal spheres. [ 35 ] Based on this achievement, another alternative method, colloidal lithography, has been well developed to fabricate multiform periodic micro/nanostructured arrays (i.e., nanoparticle arrays, nanobowl arrays, nanoring arrays, and nanopillar arrays) using these monolayer colloidal crystals as templates or masks [36][37][38][39] by chemical routes including solution-dipping strategy, wet chemical etching, and electrochemical deposition. [40][41][42][43] Such periodic micro/nanostructured array fi lms generally have special rough surfaces, which can be used as SERS-active substrates for detection and identification of organic molecules with trace concentrations. Although chemical routes based on colloidal templates possess advantages of the simple operation, low processing costs, it is still quite diffi cult to achieve micro/nanostructured arrays with very uniform morphology on large-scale by above routes. If these micro/ nanostructured arrays are applied as active substrates in SERS detection, the intensity of SERS spectra in different areas on the sample will fl uctuate in a large range, leading to the failure in practical applications. Whereas other parallel routes, based on physical process method, such as sputtering deposition, pulsed laser deposition, thermal evaporation deposition, atomic layer deposition, and so on, combining with monolayer colloidal crystals template can well resolve these problems. [ 44 ] SERS enhancement activities are mainly dependent on chemical enhancement or local electromagnetic fi eld enhancement at nanoscaled protrusions and cavities. For the latter case, the Periodic hexagonal spherical nanoparticle arrays are fabricated by a sacrificial colloidal monolayer template route by chemical deposition and further physical deposition. The regular network-structured arrays are fi rst templated by colloidal monolayers and then they are changed to novel periodic spherical nanoparticle arrays by further sputtering deposition due to multiple direction deposition and shadow effect between adjacent nanoparticles. The nanogaps between two adjacent spherical nanoparticles can be well tuned by controlling deposition time. Such periodic nanoparticle arrays with gold coatings ...

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This paper describes an effective chiral base-catalyzed biomimetic transamination of α-keto esters using simple benzyl amines. A wide variety of α-amino esters containing various functional groups can be synthesized in high enantioselectivity and reasonable yield.

Nitrogen-containing bisphosphonates (N-BP), including zoledronic acid (ZOL) and alendronate (ALD), have been proposed as sensitisers in γδ T cell immunotherapy in pre-clinical and clinical studies. Therapeutic efficacy of N-BPs is hampered by their rapid renal excretion and high affinity for bone. Liposomal formulations of N-BP have been proposed to improve accumulation in solid tumours. Liposomal ALD (L-ALD) has been suggested as a suitable alternative to liposomal ZOL (L-ZOL), due to unexpected mice death experienced in pre-clinical studies with the latter. Only one study so far has proven the therapeutic efficacy of L-ALD, in combination with γδ T cell immunotherapy, after intraperitoneal administration of γδ T cell resulting in delayed growth of ovarian cancer in mice. This study aims to assess the in vitro efficacy of L-ALD, in combination with γδ T cell immunotherapy, in a range of cancerous cell lines, using L-ZOL as a comparator. The therapeutic efficacy was tested in a pseudo-metastatic lung mouse model, following intravenous injection of γδ T cell, L-ALD or the combination. In vivo biocompatibility and organ biodistribution studies of L-N-BPs were undertaken simultaneously. Higher concentrations of L-ALD (40–60 μM) than L-ZOL (3–10 μM) were required to produce a comparative reduction in cell viability in vitro, when used in combination with γδ T cells. Significant inhibition of tumour growth was observed after treatment with both L-ALD and γδ T cells in pseudo-metastatic lung melanoma tumour-bearing mice after tail vein injection of both treatments, suggesting that therapeutically relevant concentrations of L-ALD and γδ T cell could be achieved in the tumour sites, resulting in significant delay in tumour growth.

This communication describes a chiral base-catalyzed asymmetric [1,3]-proton shift of trifluoromethyl ketimines, giving a wide variety of trifluoromethyl aldimines containing various functional groups with up to 94% ee.

The pathogenesis of rheumatoid arthritis (RA) is related to the inhibition of osteoblast differentiation.