微流控芯片基片与盖片一体化注塑成型研究

针对微流控芯片基片与盖片的结构特点,提出了定模先行抽芯机构,设计制造了微流控芯片基片与盖片一体化注塑成型模具,并进行注塑成型试验研究.结果表明:定模先行抽芯机构可以有效解决盖片上圆孔状储液池成型与脱模的技术难题,如何使微通道复制完全是微流控芯片基片注塑成型的主要技术难点;模具温度对提高微通道复制度起决定性作用,注射速度和熔体温度是次要因素,而注射压力相对其他因素影响力较差,但必须保持在一个较高的水平,依此形成塑料微流控芯片的注塑成型工艺规范.     

PDMS微流控电泳芯片的快速制备

采用Protel软件绘制微流控沟道的形状,利用电路板制作技术加工出模具.该芯片由PDMS基片和PDMS盖片组成,微流控沟道位于基片上,深度和宽度分别为75μm和100μm,由盖片对其进行密封.考察了有绝缘漆模具和无绝缘漆模具制作的芯片的电泳分离情况.在所制作的PDMS微流控电泳芯片上对用异硫氰酸酯荧光素标记的氨基酸进行了电泳分离,当信噪比S/N=3时,最小检测浓度达到0.8×10-11mol/L.     

塑料微流控芯片的注塑成型

有别于传统的微流控芯片压塑成型方法,本文提出注塑成型加工塑料微流控芯片的新工艺.采用UV-LIGA技术制作成型微通道的型芯,设计制造了微流控芯片注塑模具.充模试验表明,如何使微通道复制完全是微流控芯片注塑成型的主要技术难点.模拟与理论分析表明,熔体在微通道处出现滞流现象是复制不完全的主要原因;搭建了可视化装置对此加以试验验证.利用正交试验方法进行充模试验,研究各工艺参数对微通道复制度的影响.试验表明模具温度对提高微通道复制度起决定性作用;注射速度和熔体温度是次要因素,而注射压力相对其他因素影响力较差,但必须保持在一个较高的水平.依此形成塑料微流控芯片的注塑成型工艺,对于宽80μm、深50μm截面的微通道而言,可使微通道复制度由70%提高到90%,满足使用要求.     

微流控技术在法医DNA快速检验方面的应用

微流控芯片技术因其微型化、自动化、高通量、集成化、快速等优势使得实验室研究产生革命性的变化,并在生物化学、医学等诸多领域得到广泛应用,但目前还没有基于微流控芯片技术的国产全集成自动化DNA分析仪。该文总结微流控技术在DNA提取、PCR扩增、电泳分离等DNA检验流程方面的研究现状与进展,尤其是在法医DNA快速检验方面的研究进展,同时介绍国内外全集成式DNA分析的研究状况。全集成与功能化是目前微流控技术研究的主流方向。未来,以微流控芯片为主导的全自动、便携式、集成化的DNA分析系统,将使得法医DNA检验从实验室走进案件现场甚至日常生活,实现真正的快速即时检验。     

微流控二维芯片电泳技术在蛋白质分离分析中的应用

微流控二维芯片电泳技术因其具有分离速度快、易于微型化和自动化、接口处死体积小、可极大地改善峰容量和分辨率等优点,而在复杂的蛋白质组学研究中展现出了巨大的潜力.文中针对蛋白质微流控二维芯片电泳分离原理、芯片的设计和制作、检测技术、分离分析条件的优化等进行了综述,按二维接口模式分类讨论了徼流控二维芯片电泳技术在蛋白质分离分...     

集成电化学检测三电极体系微流控芯片的研制

本文介绍了一种在单个PMMA衬底上集成Ag-Pt-Pt两种材料微电极的方法。PMMA是一种聚合物材料,而在聚合物材料上集成两种材料电极的微流控芯片制作,需集成不同材料的电极。电化学检测常采用三电极体系,且这三个电极往往是由不同材料组成的。工作电极和对电极一般采用贵金属材料。本文研究了一种在PMMA衬底上集成Pt-Pt-Ag三电极体系的微流控芯片方法。利用可逆键合法,将集成Pt-Pt-Ag三电极体系的PMMA衬底与一片带有检测池的PDMS盖片键合到一起,研制出了一种电化学检测微流控芯片。     

基于微流控芯片的一种蛋白检测方法

利用MEMS技术制作石英玻璃材料的微流控芯片,在自行研制的紫外可见吸收检测系统上,实现了芯片上对牛血清蛋白BSA、人免疫球蛋白IgG和人转铁蛋白TRF及它们的混合溶液的分离检测,结果重复性较好。实验提供了一种微流控芯片分离检测蛋白的手段,它是一种快速低成本的检测蛋白的方法。     

毛细管微流控芯片器件研究进展EI北大核心CSCD

毛细管微流控芯片是微流控芯片领域中重要的一部分,因其具有制备难度低、材料成本低、化学性能优良以及设计灵活的独特优势而得到了广泛的应用与研究。文中对毛细管微流控芯片的基本工作原理与制作方法进行了详细叙述,重点综述了近年来毛细管微流控芯片在液滴生成、纤维纺丝等领域中的研究进展与应用,最后对目前面临的问题进行了探讨,并展望了该技术未来在标准化、高通量及灵活性等方面应用的发展方向。     

光纤型PDMS电泳芯片的制作与研究

介绍了一种光纤型PDMS电泳芯片,该芯片主要由多模光纤,PDMS盖片和基片组成.通过浇注PDMS的方法制成电泳芯片,盖片上的微流控沟道和光纤沟道的深度分别为50 μm 和90 μm,基片上的光纤沟道的深度为40 μm,实现了微流控沟道中心和光纤的中心在同一个平面上.用蓝色发光二极管作为激发光源,以异硫氰酸酯荧光素为分离物质,在自制的电泳仪上对该芯片进行测试,最小检测浓度达到1.1×10-7 mol/L,信噪比S/N=3,在1.8×10-7 mol/L～4×10-5 mol/L范围内相关系数r=0.996,结果证实了该芯片的可行性.     

微流控技术发展对计量的新挑战

一、微流控技术简介 根据美国两院院士、哈佛大学乔治·怀特塞兹(George White sides)教授2006年刊登在国际顶级科学期刊《科学》上的文章中的定义,微流控(Microfluidics)是指针对极微量体积流体(10-9L～10-18L)进行操控的科学与技术.实现微流体操控的主要方法就是将流体限制在一个微米甚至纳米尺度的通道中,而这些通道的制作手段起源于制作微电子处理芯片的半导体工艺流程.最早提出微流控这个概念的是1990年在瑞士Ciba-Geigy公司做研究的Andreas Manz教授,他最初的设想是将微机电(MEMS)与分析化学相结合,从而做出一个类似芯片能将各种功能集成在一起的微型分析仪器.当时,这样的系统被称为微全分析系统,英文是Miniaturized total analysis systems,简称为MicroTAS或μTAS.     

Transition of MEMS technology to nanofabrication

The transition of MEMS technology to nano fabrication is a solution to the growing demand for smaller and high-density feature sizes in the nanometer scale. Nanoimprint lithography (NIL) techniques for fabricating micro- and nano-features are discussed including hot embossing lithography (HEL), UV Molding (UVM) and micro contact printing (microCP). Recent results in micro and nano-pattern transfer are presented where features ranged from < 100 nm to several centimeters. We also present a comparative study between standard glass microfluidic chips and their HEL counterparts by metrology. Hot-embossed microfluidic chips are shown to be faithful replicates of their parent stamps. NIL is presented as a promising avenue for low-cost, high throughput micro and nano-device fabrication.     

Microfluidic Approaches for Microactuators: From Fabrication,Actuation, to Functionalization

Microactuators can autonomously convert external energy into specific mechanical motions. With the feature sizes varying from the micrometer to millimeter scale, microactuators offer many operation and control possibilities for miniaturized devices. In recent years, advanced microfluidic techniques have revolutionized the fabrication, actuation, and functionalization of microactuators. Microfluidics can not only facilitate fabrication with continuously changing materials but also deliver various signals to stimulate the microactuators as desired, and consequently improve microfluidic chips with multiple functions. Herein, this cross-field that systematically correlates microactuator properties and microfluidic functions is comprehensively reviewed. The fabrication strategies are classified into two types according to the flow state of the microfluids: stop-flow and continuous-flow prototyping. The working mechanism of microactuators in microfluidic chips is discussed in detail. Finally, the applications of microactuator-enriched functional chips, which include tunable imaging devices, micromanipulation tools, micromotors, and microsensors, are summarized. The existing challenges and future perspectives are also discussed. It is believed that with the rapid progress of this cutting-edge field, intelligent microsystems may realize high-throughput manipulation, characterization, and analysis of tiny objects and find broad applications in various fields, such as tissue engineering, micro/nanorobotics, and analytical devices.     

基于SU-8负胶的微流体器件的制作及研究

采用SU-8结构释放并键合玻片制作了多层结构的微流体芯片,探讨了影响芯片气密性和沟道堵塞的因素,并通过荧光显示验证,提供了一种快速、低成本的塑性微流体器件制作方法.     

无机材料喷墨制备新方法的进展

近年来, 喷墨制备技术被用于无机材料复杂三维结构无模成型和材料芯片的制备中, 受到了国内外研究人员的广泛关注. 本文综述了喷墨制备技术在无机材料多个方面的研究进展, 包括不同驱动模式的喷墨设备选择, 材料墨水的性能、无机材料复杂结构和材料芯片喷墨制备过程中存在的问题以及目前研究的热点问题等. 并介绍了作者在喷墨制备应用研究方面的进展, 包括电极制作和制备材料芯片用电磁式喷墨打印设备的建立.     

利用CO2激光法快速制造PMMA基材的微流控分析芯片

提出一种广泛使用的CO2激光法,以直接读写烧蚀的方式,进行快速的聚甲基丙烯酸甲酯（PMMA）基材的微流控分析芯片的制造.利用此方法所制造的微流道,将以扫描电子显微镜（SEM）、原子力显微镜（AFM）及表面轮廓仪进行各项表面性质的分析.本文所发展的CO2激光烧蚀法,提供了一个可广泛使用及具有经济效应的PMMA基材的微流控分析芯片的制造方法.在此激光制程法中,微流控分析芯片的制造图案可由商业的套装软件绘制而成,再传输至激光系统中进行烧蚀微管道,结果显示利用离焦法的激光制程技术,在没有退火处理的情况下,就可以获得表面相当平滑的微流道,表面粗糙度小于4nm.     

微流控芯片制作及电特性研究

采用热压和键合的方法制作玻璃和有机聚合物(PMMA)芯片,对玻璃和PMMA芯片在高压直流电场作用下的伏安特性进行了研究和分析。实验表明,玻璃芯片的伏安线性区域为1100V,PMMA芯片为700V,由于玻璃的导热性能优于PMMA,所以玻璃芯片的伏安线性区域大于PMMA芯片。在此线性段内,根据基尔霍夫电流定律将芯片简化为等效电阻模型,研究了分离电压以及分离焦耳热对芯片分离效果的影响因素,为微流控芯片的优化设计提供了理论依据。     

Microfluidic Platforms toward Rational Material Fabrication for Biomedical Applications

The emergence of micro/nanomaterials in recent decades has brought promising alternative approaches in various biomedicine‐related fields such as pharmaceutics, diagnostics, and therapeutics. These micro/nanomaterials for specific biomedical applications shall possess tailored properties and functionalities that are closely correlated to their geometries, structures, and compositions, therefore placing extremely high demands for manufacturing techniques. Owing to the superior capabilities in manipulating fluids and droplets at microscale, microfluidics has offered robust and versatile platform technologies enabling rational design and fabrication of micro/nanomaterials with precisely controlled geometries, structures and compositions in high throughput manners, making them excellent candidates for a variety of biomedical applications. This review briefly summarizes the progress of microfluidics in the fabrication of various micro/nanomaterials ranging from 0D (particles), 1D (fibers) to 2D/3D (film and bulk materials) materials with controllable geometries, structures, and compositions. The applications of these microfluidic‐based materials in the fields of diagnostics, drug delivery, organs‐on‐chips, tissue engineering, and stimuli‐responsive biodevices are introduced. Finally, an outlook is discussed on the future direction of microfluidic platforms for generating materials with superior properties and on‐demand functionalities. The integration of new materials and techniques with microfluidics will pave new avenues for preparing advanced micro/nanomaterials with enhanced performance for biomedical applications.     

In-Plane Integration of Polymer Microfluidic Channels With Optical Waveguides– A Preliminary Investigation

The next major challenges for lab-on-a-chip (LoC) technology are 1) the integration of microfluidics with optical detection technologies and 2) the large-scale production of devices at a low cost. In this paper the fabrication and characterisation of a simple optical LoC platform comprising integrated multimode waveguides and microfluidic channels based on a photo-patternable acrylate based polymer is reported. The polymer can be patterned into both waveguides and microfluidic channels using photolithography. Devices are therefore both quick and cost-effective to fabricate, resulting in chips that are potentially disposable. The devices are designed to be highly sensitive, using an in-plane direct excitation configuration in which waveguides intersect the microfluidic channel orthogonally. The waveguides are used both to guide the excitation light and to collect the fluorescence signal from the analyte. The potential of the device to be used for fluorescence measurements is demonstrated using an aqueous solution of sodium fluorescein. A detection limit of 7 nM is achieved. The possibilities offered by such a device design, in providing a cost-effective and disposable measurement system based on the integration of optical waveguides with LoC technology is discussed.     

Preparation and application of microfluidic SERS substrate:Challenges and future perspectives

Surface-enhanced Raman spectroscopy(SERS), as a highly sensitive molecular analysis technique, can realize fast and non-destructive detection of the information of molecular bonds to identify the component of analytes by "fingerprint" identification. The preparation of SERS substrates plays an extremely important role in the development of SERS technology and the application of SERS detection. By integrating SERS enhancement substrates into microfluidic chips, researchers have developed the microfluidic SERS chips which expand the function of microfluidic chips and provide an efficient platform for on-site biochemical analysis equipped with the powerful sensing capability of SERS technique. In this paper, we will first briefly give a review of the current microfluidic SERS-active substrates preparation technology and present the perspective on the application prospects of microfluidic SERS-active substrates. And then the challenges in the preparation of microfluidic SERS-active substrates will be pointed out, as well as realistic issues of using this technology for biochemical application.