基于PMMA材料的微流控芯片批量注塑技术研究

微流控芯片可以操控微纳尺度上流体,借助尺度效应的帮助进行检测,具有检测过程迅速、检测准确、试剂消耗量小等特点,常应用于高效筛选、分析化学、食品安全、环境检测等领域。伴随微流控技术的发展,聚合物材料逐渐取代传统的玻璃、硅等材料成为微流控芯片的主流基体材料。面向聚甲基丙烯酸甲酯(PMMA)材质的微流控芯片,开展了设计、数值模拟仿真、注塑模具设计及微流控芯片注塑成型的全过程研究,对未来微流控芯片的大规模注塑制备具有一定借鉴意义,最后也对未来微流控芯片与注塑加工工艺相结合的发展趋势进行了展望。     

微流控芯片UV固化微流道复制精度研究

研究了一种改进型紫外光(UV)固化注射成型装置,利用线型紫外光源辐照加工微流控芯片,并对微流控芯片上的微流道的复制精度进行研究。结果表明,该工艺成型的微结构制品复制精度较好,在相同工艺条件下,制品上的微结构轮廓曲线重合度高;光源的扫描速率对制品的成型精度有重要的影响,适当的光源扫描速率下,制品的微结构轮廓复制精度较高;充模压力的大小对制品的复制精度也有一定影响。     

基于PMMA材料的微通道快速加工技术

近年来,基于聚合物的微加工制造技术已经成为微细加工领域的研究热点,已广泛应用于制备芯片实验室和微流控芯片。以热压技术为基础,研究利用加热电阻丝制备微流控芯片微通道的快速加工技术,并最终实现了基于聚甲基丙烯酸甲酯(PMMA)材料的微通道快速加工,获得了电阻丝压印微通道的最优条件,在电流1. 8 A、时间5s、压力为44. 59 N条件下获得的微通道宽度变形率约为8. 5%,深度变形量约为8. 9%,可以在2 h左右制备完成PMMA微流控芯片。最后,利用该加工技术制作了十字型流动聚焦型微流控芯片,可稳定生成34～74 nL范围内的微液滴,实验结果显示利用本快速加工技术所获得的微通道圆润光滑、性能稳定、键合密封牢固。     

基于离心力驱动微流控芯片的研究进展

离心力驱动微流控芯片具有制作成本低、集成度高等优势,是一种不可多得的微流体驱动技术,文中介绍了离心力驱动微流控芯片的驱动原理和加工方法并对其优缺点进行了比较,综述了离心式芯片在生物、医疗和化工等领域应用及发展前景。     

微流控芯片超声振动注射成型模具设计

针对目前微流控芯片注射成型中微通道充填困难、成型精度低等问题,研究超声振动辅助注射成型微流控芯片的方法,设计出微流控芯片超声振动模具。创新性地引入热流道系统,实现了超声振动系统与注射成型模具的有效集成;独特的流道和型腔布置实现了芯片的基片和盖片同模同时成型;改进的二次顶出机构实现了芯片的无损脱模。     

微流控芯片技术的现状与发展

简要叙述微流控芯片的定义及应用,介绍几种制作微流控芯片的方法,分析微流控芯片成型中的关键技术,如:压力、温度、时间等.综合国内外发展,结合当前微流控芯片的现状,提出微流控芯片在一些方面的尝试和探讨.     

PMMA微流控芯片最佳注射成型工艺的实验研究

以聚甲基丙烯酸甲酯(PMMA)为原料,通过注塑加工的方式制备微流控芯片,经过多次注塑实验得出影响PMMA微流控芯片成型质量的主要因素是:模具温度、保压压力、熔体温度和注射速度.在其他参数不变的情况下,通过正交实验和极差分析确定了PMMA微流控芯片注射成型的最佳工艺:熔体温度260℃,模具温度50℃,保压压力60 MPa...     

聚二甲基硅氧烷的性能特点及其典型应用

正聚二甲基硅氧烷PDMS因具有良好的机械性能、光学性能、化学稳定性和生物兼容性,且易于加工成型、价格低廉,近年来已成为一些工业领域里产品加工的首选材料。特别是制备微流控芯片由于自身内部的多孔分子网络允许小分子穿透,使得PDMS在对气体或其他小分子交换有需求的细胞培养类微流控芯片等芯片应用中脱颖而出。聚二甲基硅氧烷作为有机硅材料中的一种,由于其特殊结构和优异的性能,在建筑、汽车、电子电气、航空航天等     

基于CAE分析的工艺参数对微结构复制程度的影响

针对注射成型中微流控芯片中微结构复制不完全的情况,采用单因素法,利用Moldflow软件对微流控芯片抽象物理模型进行仿真分析,考察熔体温度、模具温度、保压压力、注射压力等4个工艺参数对微结构复制情况的影响。结果表明,熔体温度与模具温度的影响较大,保压压力的影响次之,注射压力的影响不显著。     

微流控芯片中微滴的形成及其在生物医学分析中应用

微流控芯片微滴技术具有可形成粒径均匀可控的微滴,能实现试剂快速混合、反应通量高、样品组分间无交叉污染等优点。综述微流控芯片中微滴的形成方法及微滴技术在生物分析及化学领域的应用研究进展。     

微流控芯片的紫外光固化注射成型工艺对微结构的影响

研制了紫外（UV）光固化注射成型机,对微流控芯片的微结构复制度进行了研究。结果表明,提高保压压力,填充能力得到提升,复制度提高;光照强度对微结构复制度影响较小,原因是光照强度对收缩总量的影响较小;低黏度树脂混合物有利于微结构的填充,但是黏度过低会使得收缩量变大,复制度反而降低;与传统注射成型相比,该方法复制度较高。     

Analysis of mold insert fabrication for the processing of microfluidic chip

The microfluidic chip has been used as an example to discuss different mold insert materials by micro hot‐embossing molding. For the mold insert, this study uses the SU‐8 photoresist to coat on the silicon wafer, then uses UV light to expose the pattern on the surface of SU‐8 photoresist, and coat the seed layer on the SU‐8 structure using thermal evaporation. The micro electroforming technology has been combined to fabricate the mold inserts (Ni, Ni‐Co) followed by replicating the microstructure from the metal mold insert by micro‐hot embossing molding. Different processing parameters (Embossing temperature, embossing pressure, embossing time, and demolding temperature) for the properties of COP film of microfluidic chip have been discussed. The results show that the most important parameter is the embossing temperature for replication properties of molded microfluidic chip. The demolding temperature is the most important parameter for surface roughness of the molded microfluidic chip. The Ni‐Co mold insert is the most suitable mold material for molded microfluidic chip by microhot embossing molding. The bonding temperature is the most important factor for the bonding strength of sealed microfluidic chip by tensile bonding test. POLYM. ENG. SCI., 2009. © 2008 Society of Plastics Engineers     

聚(双环戊二烯-co-环辛二烯)微流控芯片的制备

本文报道了聚(双环戊二烯-co-环辛二烯)微流控芯片的制备方法。引入环辛二烯作为共聚单体,与双环戊二烯通过开环易位聚合制备得到弹性共聚物。当环戊二烯与环辛烯的质量比是1 : 1时,制得共聚物的力学性能接近于聚二甲基硅氧烷(PDMS),弹性共聚物具有较高的微尺寸结构成型精度。利用聚双环戊二烯半固化凝胶的反应特性,实现共聚物与聚双环戊二烯基底之间的稳定键合。共聚物微流控芯片可以通过类似于PDMS的连接方式,实现简单、高效的密封连接。利用共聚物微流控芯片制得单分散的微液滴,控制连续相的流速即可实现微液滴尺寸的调变。关键词：聚双环戊二烯共聚物；环辛烯；弹性体；微流控芯片；单分散液滴；中图分类号：TQ630 文献标识码： A 文章编号：1003-5214 (2020) 01-0000-00     

Fabrication and Applications of Microfluidic Devices: A Review

Microfluidics is a relatively newly emerged field based on the combined principles of physics, chemistry, biology, fluid dynamics, microelectronics, and material science. Various materials can be processed into miniaturized chips containing channels and chambers in the microscale range. A diverse repertoire of methods can be chosen to manufacture such platforms of desired size, shape, and geometry. Whether they are used alone or in combination with other devices, microfluidic chips can be employed in nanoparticle preparation, drug encapsulation, delivery, and targeting, cell analysis, diagnosis, and cell culture. This paper presents microfluidic technology in terms of the available platform materials and fabrication techniques, also focusing on the biomedical applications of these remarkable devices.     

Fabrication of microfluidic chips using controlled dissolution of 3D printed scaffolds

Microfluidic chips are commonly fabricated using soft lithography, which often requires a clean room and micropatterning equipment. Recently, microfluidic chips are increasingly fabricated using 3D printing, but this technology is still limited in smallest channel printability, transparency, supports residue, and biocompatibility. In this work, a simple, fast, and inexpensive step is introduced to fabricate polydimethylsiloxane (PDMS) microfluidic chips using enhanced internal scaffold removal (eISR). It is found that final channel dimension decreases by 0.22 ± 0.02 μm/revolution with a 7% error using eISR. Surface topology is inspected after dissolution using scanning electron microscopy. A T-junction device, bifurcation channels, and curved channels are fabricated to demonstrate the usability of eISR in multiple applications. Compared to previous methods, eISR provides acrylonitrile–butadiene–styrene dissolution before PDMS casting to achieve thinner and smoother channels produced using a commercial 3D printer.     

Chemically functionalized graphene/polymer nanocomposites as light heating platform

Chemically functionalized graphene (CFG) is proposed as a novel nanoscale optical heater by uniformly dispersing it in poly(dimethylsiloxane) (PDMS) matrix. And subsequently, a simple, fast, and localized heating method on microfluidic chips is demonstrated. CFG is prepared through simultaneous modification and reduction of graphene oxide with dodecylamine by a solvothermal route. It is well dispersed in PDMS suspension to form uniform CFG/PDMS composite due to the presence of the long‐dodecyl chain. The obtained CFG/PDMS composites are readily made into microfluidic chips by standard soft lithography. The localized optical heating on the chip is realized by employing a conventional semiconductor laser as light source. The prepared chips with low to 0.05 wt% CFG contents can exhibit temperature increase (<1 min) at very low power illumination. The optical heating effects were observed not only under irradiation with long wavelength, but also under the wavelengths as short as 405 nm. Our studies illustrated that CFG/PDMS composite can serve as a practical optical heating platform for microfluidic chips with the advantages of simple, low cost, and high efficiency. POLYM. COMPOS., 37:1350–1358, 2016. © 2014 Society of Plastics Engineers     

三维复杂微流体纺丝芯片的封装研究

为了拓展微流体芯片的应用领域,以一种具有三层结构的多功能集成微流体纺丝芯片为例,利用去离子水和再生丝素蛋白水溶液,比较了环氧树脂粘合剂、硅胶粘合剂以及压敏胶对聚二甲基硅氧烷(PDMS)和纤维素膜的粘合效果,探讨了等离子处理、封装方式等三维复杂微流体芯片的封装技术,实现了多功能集成微流体纺丝芯片的有效封装,对具有类似结构的三维复杂微流体芯片的封装提供参考。     

Microinjection molding of plastic microfluidic chips including circular microchannels

In this study, a microfluidic chip prototype having circular microchannels was replicated by microinjection molding process, employing a modularized and sectioned micromold system (MSMS). In the viewpoint of microfluidic manipulation, a microchannel with circular cross‐section shows several advantages over a conventional rectangular and/or square microchannel. To achieve a mass production of the microchannels with circular or round cross‐sections, the micromold was designed and fabricated based on the concept of MSMS. It consisted of several micromold modules, each having half‐circular cross‐sectional microstructures on its one‐side surface. The modules were precisely manufactured by a deep X‐ray lithography using a synchrotron radiation and a subsequent nickel electroforming process. Then, the MSMS for a microinjection molding process was constructed by assembling the nickel modules. After the molding of plastic plate with open microchannels of half‐circular cross‐section, a thermal bonding of microinjection‐molded plates was carried out to produce the microfluidic chip prototype including the circular microchannels. Observation of the surface quality, measurement of cross‐sectional profiles, and microfluidic test were carried out, which verified the usefulness of the present fabrication process. POLYM. ENG. SCI., 54:42–50, 2014. © 2013 Society of Plastics Engineers