微流体

Abstract(#br)The hydrophobic characteristics of PDMS and non-specific protein adsorption are major drawbacks for its application in biosensing. Here we have combined surface oxidation by plasma and chemical binding of polyvinyl alcohol (PVA) to obtain long-term stability of hydrophilic PDMS surfaces. Mercaptopropyltrimethoxisilane and aminopropyltrimethoxisilane were used as adhesives between the plasma-oxidized PDMS surface and the PVA, immobilized at room temperature.

Abstract(#br)An experimental investigation was conducted to study the relative hydrodynamic and thermal performance of microfluidic, constructal-based, self-similar bifurcated flow channel arrangements with branching angles of 90°. The complexity of the microchannel arrangement was varied from zero to three bifurcation levels while the heat transfer area was held constant for all complexity levels. Constraining the area facilitates comparison of the thermal performance of test sections of different complexities.

Abstract(#br)A microfluidic device containing a constructal-based branched flow structure with an externally controllable complexity was developed and tested in this study. The device was fabricated in the form of a 10\u003cce:hsp sp=\"0.25\"/\u003emm square by 9\u003cce:hsp sp=\"0.25\"/\u003emm high monolithic silicon/polydimethylsiloxane (PDMS) test section which contains three interconnected flow channels in a tee configuration.

Abstract(#br)This article reports on the fabrication of a disposable bio-nano-chip (BNC), a microfluidic device composed of polydimethylsiloxane (PDMS) and thiolene-based optical epoxy which is both cost-effective and suitable for high performance immunoassays.

Abstract(#br)Here we present a capillary-driven microfluidic chip for “one-step” immunoassays. The chip allows for easy modification of several assay parameters such as the flow rates of sample, the volumes of samples for tests, and the type of reagents and receptors for detecting analytes. We therefore term such a chip a multiparametric chip and illustrate this concept with the integration and release of anti-C-reactive protein (CRP) detection antibodies (dAbs) together with splitting flow of samples containing CRP across lines of anti-CRP capture antibodies (cAbs).

Abstract(#br)We present the application of a composite material, consisting of a ferromagnetic neodymium powder and a silicone elastomer, alone to realize a microfluidic network with pressure sensitive passive valves. The mixing ratio of the composite and the degree of magnetization can be utilized to adjust the switching point of each single valve. By combining differently adjusted valves within a microfluidic network it is possible to realize a sort of liquid logic and to control the flow in the network just by changing the inward flow respectively pressure.

Abstract(#br)Investigations on surface properties of poly(dimethylsiloxane) (PDMS) are justified by its large application ranges especially as coating polymer in fluidic devices. At a micrometer scale, the liquid dynamics is strongly modified by interactions with a solid surface. A crucial parameter for this process is microchannel wettability that can be tuned by acting on surface chemistry and topography. In literature, a number of multi-step, time and cost consuming chemical and physical procedures are reported.

Abstract(#br)We recently developed a novel composite photopolymerizable material which allows the holographic recording of diffraction gratings with optimal optical and mechanical properties (high diffraction efficiency, transparency and spatial resolution, low shrinkage, long time stability). This material was successfully used to produce a low cost and easy to make optically pumped, organic distributed feedback laser, working on the first diffraction order of a high quality Bragg grating doped with a photoluminescent dye.

摘要 聚二甲基硅氧烷( PDMS )是一种硅橡胶，具有良好的柔韧性、光学透明性和生物相容性。因此，在硅玻璃等透明材料上制备柔性微光学元件，可以为微流控领域的应用提供可能。我们用质子束( PBW ) ( 1.0 MeV束)在硅玻璃上制备了具有曲面的PDMS微结构。我们发现，硅玻璃上13μm厚的PDMS薄膜仅对600 nC / mm2以上的质子注量敏感，而使用硅衬底时，对4.0 nC / mm2的质子注量敏感。基于PBW过程中硅玻璃表面充电导致有效灵敏度降低的假设，采用Au溅射的方法对硅玻璃表面进行镀膜。在2.0 nC / mm2的条件下，我们可以观察到金包硅玻璃上PDMS的形成。在半透明镀金硅玻璃上制备了高度为13 μm，直径为40 μm的弯曲PDMS结构阵列。

Abstract(#br)Pancreatic islet transplantation is a promising method for treatment of type 1 diabetes mellitus. However, transplanted islets can be destroyed due to host immune reactions. To immunologically protect transplanted islets, here an immunoprotective microfiber including islets by using a polydimethylsiloxane (PDMS)-based microfluidic device is newly designed. A cylindrical-flow channel in the microfluidic platform is used for producing collagen-alginate composite (CAC) fibers. This enables mass production and uniform diameter distribution (\u003c250 μm) without protruding islets.