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101.
Buxboim A Bar-Dagan M Frydman V Zbaida D Morpurgo M Bar-Ziv R 《Small (Weinheim an der Bergstrasse, Germany)》2007,3(3):500-510
We have developed a biochip platform technology suitable for controlled cell-free gene expression at the micrometer scale. A new hybrid molecule, "Daisy", was designed and synthesized to form in a single step a biocompatible lithographic interface on silicon dioxide. A protocol is described for the immobilization of linear DNA molecules thousands of base pairs long on Daisy-coated surfaces with submicrometer spatial resolution and up to high densities. On-chip protein synthesis can be obtained with a dynamic range of up to four orders of magnitude and minimal nonspecific activity. En route to on-chip artificial gene circuits, a simple two-stage gene cascade was built, in which the protein synthesized at the first location diffuses to regulate the synthesis of another protein at a second location. We demonstrate the capture of proteins from crude extract onto micrometer-scale designated traps, an important step for the formation of miniaturized self-assembled protein chips. Our biochip platform can be combined with elastomeric microfluidic devices, thereby opening possibilities for isolated and confined reaction chambers and artificial cells in which the transport of products and reagents is done by diffusion and flow. The Daisy molecule and described approach enables groups not proficient in surface chemistry to construct active biochips based on cell-free gene expression. 相似文献
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Microelectromechanical systems (MEMS) are poised to bring the next technology revolution. At present, many of these are fabricated
from silicon using lithographic techniques developed in the microelectronics industry. Due to the large surface area to volume
ratio on the micrometer scale, surface forces, such as adhesion and friction, are often detrimental to the fabrication and
operation of MEMS devices. Thus, one of the key issues in MEMS is surface engineering to reduce adhesion and friction. Here,
we present a general strategy for the efficient assembly of organic layers directly onto the silicon surface in both vacuum
environment and solution phases via the robust Si–N or Si–O linkage. This is achieved by the reaction between an amine or
alcohol functional group and a chlorinated Si surface. The resulting surface assemblies are thermally stable. Characterization
by interfacial force microscope (IFM) reveals that these assemblies have very low surface energy and are mechanically stable.
This revised version was published online in September 2006 with corrections to the Cover Date. 相似文献
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Eunil Hahm Ahla Jo Eun Ji Kang Sungje Bock Xuan-Hung Pham Hyejin Chang Bong-Hyun Jun 《International journal of molecular sciences》2021,22(21)
To study the distance-dependent electromagnetic field effects related to the enhancement and quenching mechanism of surface-enhanced Raman scattering (SERS) or fluorescence, it is essential to precisely control the distance from the surface of the metal nanoparticle (NP) to the target molecule by using a dielectric layer (e.g., SiO2, TiO2, and Al2O3). However, precisely controlling the thickness of this dielectric layer is challenging. Herein, we present a facile approach to control the thickness of the silica shell on silver nanoparticle-assembled silica nanocomposites, SiO2@Ag NPs, by controlling the number of reacting SiO2@Ag NPs and the silica precursor. Uniform silica shells with thicknesses in the range 5–40 nm were successfully fabricated. The proposed method for creating a homogeneous, precise, and fine silica coating on nanocomposites can potentially contribute to a comprehensive understanding of the distance-dependent electromagnetic field effects and optical properties of metal NPs. 相似文献
107.
V. V. Tsukruk 《Advanced materials (Deerfield Beach, Fla.)》2001,13(2):95-108
Research advances in molecular coatings from functional polymeric and organic molecules designed as molecular lubricants or molecular glues for micro‐ and nanodevices are presented here, with a focus on organized molecular films from amphiphilic molecules, molecules with reactive ends and functional oligomers. The interfacial properties of molecular coatings critical for their lubrication (see Figure) or adhesive performance at the nanoscale are discussed in conjunction with results on molecular structure and morphology of these coatings. Examples of the latest developments in the field of nanocomposite molecular coatings and applications of molecular lubrication concepts for computer hard drives are presented. 相似文献
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阐述了装配式装修的概念、优势和BIM技术在装配式装修行业的应用现状.结合BIM软件,从族库建立、参数化建模、碰撞检查、施工图出图、工程算量等方面提出了装配式装修设计的技术路线.以全装配式装修研发实验房项目为例,详细介绍了装配式装修BIM设计过程,验证了技术思路的可行性与合理性,为推动BIM技术在装配式装修行业的应用提供... 相似文献
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