微流体

Abstract(#br)Polydimethylsiloxane (PDMS) is one of the most widely used materials for the fabrication of microfluidic devices. The uncomplicated integration of ion-exchange membranes, such as Nafion ® , would facilitate manifold electrochemical processes in microfluidics. However, the Nafion ionomer does not directly bond with cross-linked PDMS and the assembly of the membrane and PDMS substrate still remains a technological challenge.

Abstract(#br)Loop-mediated isothermal amplification (LAMP) is a DNA amplification approach characterized by high sensitivity and specificity. In “digital LAMP”, small quantities of both template DNA and reagents are encapsulated within a droplet or microwell, allowing for analysis of precious nucleic acid samples in shorter amounts of time relative to traditional DNA amplification protocols (e.g., PCR) with an improved limit of detection. In this study, an integrated, self-driven microfluidic chip was designed to carry out digital LAMP.

Abstract(#br)It is of great importance to understand biochemical system's behavior toward environmental perturbation during the development of living organisms. Here a microfluidic platform for Drosophila embryo's online development and observation is presented. The system is capable of developing the embryo's anterior and posterior halves controlled at different temperature environments, and it can be easily coupled with a confocal microscope for real-time image acquisition.

Abstract(#br)Coupling infrared (IR) spectroscopy to microfluidic devices provides a powerful tool for characterizing complex chemical and biochemical reactions. Examples of microfluidic devices coupled with infrared spectroscopy have been limited, however, largely due to the difficulties associated with fabricating systems in common infrared transparent materials like CaF 2 . Recent reports have shown that polydimethylsiloxane (PDMS) can be used as an IR transparent substrate when fabricated with thin layers.

Abstract(#br)We present a self-discretization and zero-water-loss microfluidic digital PCR (dPCR) device to enable low-cost and robust quantitative nucleic acid assays. In this device, a thin void is integrated beneath the reaction chamber array. By utilizing the permeability of polydimethylsiloxane (PDMS) film, the integrated void serves a dual function: vacuum “accumulator” and hydration “reservoir”.

This work reports on diverse technologies implemented for fabricating microfluidic devices such as biomedical micro sensors, micro pumps, bioreactors and micro separators. UV depth lithography and soft lithography were applied in the fabrication processes using different materials, for example SU-8, polydimethylsiloxane (PDMS), silicon, glass and ceramics. Descriptions of the fabrication process of completed devices and their performance are provided. Experimental tests and results are presented where available.

本文报道了一种由PDMS (聚二甲基硅氧烷)微腔、金属电极、驻极体板组成的新型能量采集器装置液室单元。在微流体腔中，由于气-液界面介电常数的变化，K掺杂到氧化硅层中，形成驻极体中的固定电荷并极化产生电能。我们预见心跳作为外部振动源，将液体泵入液细胞单元中。可以产生电流给肌萎缩侧索硬化症的膈肌节拍器等小型植入式医用电子充电。

AbstractThe polymer polydimethylsiloxane (PDMS) is widely used to build microfluidic devices compatible with cell culture. Whilst convenient in manufacture, PDMS has the disadvantage that it can absorb small molecules such as drugs. In microfluidic devices like “Organs-on-Chip”, designed to examine cell behavior and test the effects of drugs, this might impact drug bioavailability. Here we developed an assay to compare the absorption of a test set of four cardiac drugs by PDMS based on measuring the residual non-absorbed compound by High Pressure Liquid Chromatography (HPLC).

Highlights•A microfluidic platform was designed for single cells trapping.•Trapping mechanism is based on the automatic variation of hydraulic resistance.•Presenting platform allowed a single cell trapping efficiency of around 40%.•A chaotic mixing element was integrated to deliver patterns of particles to cells.;AbstractTraditionally, in vitro investigations on biology and physiology of cells rely on averaging the responses eliciting from heterogeneous cell populations, thus being unsuitable for assessing individual cell behaviors in response to external stimulations.

Abstract\n\t\t\t\t\n\t\t\t\t\tA novel, miniaturized, high-efficiency photocatalytic cell, able to work in dynamic conditions, has been designed and validated in this study. Microfluidic channels were molded out of polydimethylsiloxane (PDMS) by means of standard soft lithography techniques, so as to work as photocatalytic cells, where the coupling of anatase titanium dioxide thin films and platinum electrodes, allows an electrically assisted photocatalytic reaction to produce dissolved oxygen gas from the water content of flowing fluid (e.g. blood).