共查询到20条相似文献，搜索用时 735 毫秒
1.
Hiroaki Takehara Akira Nagaoka Jun Noguchi Takanori Akagi Takamasa Sakai Ung-il Chung Haruo Kasai Takanori Ichiki 《Biomicrofluidics》2013,7(5)
Hydrogels have several excellent characteristics suitable for biomedical use such as softness, biological inertness and solute permeability. Hence, integrating hydrogels into microfluidic devices is a promising approach for providing additional functions such as biocompatibility and porosity, to microfluidic devices. However, the poor mechanical strength of hydrogels has severely limited device design and fabrication. A tetra-poly(ethylene glycol) (tetra-PEG) hydrogel synthesized recently has high mechanical strength and is expected to overcome such a limitation. In this research, we have comprehensively studied the implementation of tetra-PEG gel into microfluidic device technology. First, the fabrication of tetra-PEG gel/PDMS hybrid microchannels was established by developing a simple and robust bonding technique. Second, some fundamental features of tetra-PEG gel/PDMS hybrid microchannels, particularly fluid flow and mass transfer, were studied. Finally, to demonstrate the unique application of tetra-PEG-gel-integrated microfluidic devices, the generation of patterned chemical modulation with the maximum concentration gradient: 10% per 20 μm in a hydrogel was performed. The techniques developed in this study are expected to provide fundamental and beneficial methods of developing various microfluidic devices for life science and biomedical applications. 相似文献
2.
Fabrication of microfluidic devices using polydimethylsiloxane 总被引：1，自引：0，他引：1
Polydimethylsiloxane (PDMS) is nearly ubiquitous in microfluidic devices, being easy to work with, economical, and transparent. A detailed protocol is provided here for using PDMS in the fabrication of microfluidic devices to aid those interested in using the material in their work, with information on the many potential ways the material may be used for novel devices. 相似文献
3.
This paper reports the use of microfluidic approaches for the fabrication of yeastosomes (yeast-celloidosomes) based on self-assembly of yeast cells onto liquid-solid or liquid-gas interfaces. Precise control over fluidic flows in droplet- and bubble-forming microfluidic devices allows production of monodispersed, size-selected templates. The general strategy to organize and assemble living cells is to tune electrostatic attractions between the template (gel or gas core) and the cells via surface charging. Layer-by-Layer (LbL) polyelectrolyte deposition was employed to invert or enhance charges of solid surfaces. We demonstrated the ability to produce high-quality, monolayer-shelled yeastosome structures under proper conditions when sufficient electrostatic driving forces are present. The combination of microfluidic fabrication with cell self-assembly enables a versatile platform for designing synthetic hierarchy bio-structures. 相似文献
4.
Danny Bavli Elishai Ezra Daniel Kitsberg Margarita Vosk-Artzi Shashi K. Murthy Yaakov Nahmias 《Biomicrofluidics》2016,10(2)
Cell-cell interactions play a key role in regeneration, differentiation, and basic tissue function taking place under physiological shear forces. However, current solutions to mimic such interactions by micro-patterning cells within microfluidic devices have low resolution, high fabrication complexity, and are limited to one or two cell types. Here, we present a microfluidic platform capable of laminar patterning of any biotin-labeled peptide using streptavidin-based surface chemistry. The design permits the generation of arbitrary cell patterns from heterogeneous mixtures in microfluidic devices. We demonstrate the robust co-patterning of α-CD24, α-ASGPR-1, and α-Tie2 antibodies for rapid isolation and co-patterning of mixtures of hepatocytes and endothelial cells. In addition to one-step isolation and patterning, our design permits step-wise patterning of multiple cell types and empty spaces to create complex cellular geometries in vitro. In conclusion, we developed a microfluidic device that permits the generation of perfusable tissue-like patterns in microfluidic devices by directly injecting complex cell mixtures such as differentiated stem cells or tissue digests with minimal sample preparation. 相似文献
5.
Three-dimensional microfluidics holds great promise for large-scale integration of versatile, digitalized, and multitasking fluidic manipulations for biological and clinical applications. Successful translation of microfluidic toolsets to these purposes faces persistent technical challenges, such as reliable system-level packaging, device assembly and alignment, and world-to-chip interface. In this paper, we extended our previously established fit-to-flow (F2F) world-to-chip interconnection scheme to a complete system-level assembly strategy that addresses the three-dimensional microfluidic integration on demand. The modular F2F assembly consists of an interfacial chip, pluggable alignment modules, and multiple monolithic layers of microfluidic channels, through which convoluted three-dimensional microfluidic networks can be easily assembled and readily sealed with the capability of reconfigurable fluid flow. The monolithic laser-micromachining process simplifies and standardizes the fabrication of single-layer pluggable polymeric modules, which can be mass-produced as the renowned Lego® building blocks. In addition, interlocking features are implemented between the plug-and-play microfluidic chips and the complementary alignment modules through the F2F assembly, resulting in facile and secure alignment with average misalignment of 45 μm. Importantly, the 3D multilayer microfluidic assembly has a comparable sealing performance as the conventional single-layer devices, providing an average leakage pressure of 38.47 kPa. The modular reconfigurability of the system-level reversible packaging concept has been demonstrated by re-routing microfluidic flows through interchangeable modular microchannel layers. 相似文献
6.
Edwards TL Harper JC Polsky R Lopez DM Wheeler DR Allen AC Brozik SM 《Biomicrofluidics》2011,5(4):44115-4411514
Herein is described the fabrication and use of a plastic multilayer 3-channel microfluidic fixture. Multilayer devices were produced by laser machining of plastic polymethylmethacrylate and polyethyleneterapthalate laminates by ablation. The fixture consisted of an array of nine individually addressable gold or gold/ITO working electrodes, and a resistive platinum heating element. Laser machining of both the fluidic pathways in the plastic laminates, and the stencil masks used for thermal evaporation to form electrode regions on the plastic laminates, enabled rapid and inexpensive implementation of design changes. Electrochemiluminescence reactions in the fixture were achieved and monitored through ITO electrodes. Electroaddressable aryl diazonium chemistry was employed to selectively pattern gold electrodes for electrochemical multianalyte DNA detection from double stranded DNA (dsDNA) samples. Electrochemical detection of dsDNA was achieved by melting of dsDNA molecules in solution with the integrated heater, allowing detection of DNA sequences specific to breast and colorectal cancers with a non-specific binding control. Following detection, the array surface could be renewed via high temperature (95 °C) stripping using the integrated heating element. This versatile and simple method for prototyping devices shows potential for further development of highly integrated, multi-functional bioanalytical devices. 相似文献
7.
Cancan Zhang Xiaolei Yu Sujian You Bo Cai Huiqin Liu Lingling Zhang Lang Rao Wei Liu Shi-Shang Guo Xing-Zhong Zhao 《Biomicrofluidics》2016,10(2)
We report on the feasible fabrication of microfluidic devices for ferroelectric polymers'' synthesis in a rapid and stable fashion. Utilizing micro-mixing and flow-focusing in microchannels, poly(vinylidene fluoride-trifluoroethylene) and copper phthalocyanine are uniformly dispersed in one hydrogel particle, which are then demonstrated to immediate and complete on-chip steady polymerization by moderate ultraviolet treatment. The advantage of our droplet-based microfluidic devices is generating versatile particles from simple spheres to disks or rods, and the lengths of particles can be precisely tuned from 30 to 400 μm through adjusting the flow rates of both disperse and oil phases. In addition, this mixed technique allows for the continuous production of dielectric microparticles with controlled dielectric properties between 10 and 160. Such a microfluidic device offers a flexible platform for multiferroic applications. 相似文献
8.
In this paper a method of electrospinning conducting and nonconducting biphasic Janus nanofibers using microfluidic polydimethylsiloxane (PDMS)-based manifolds is described. Key benefits of using microfluidic devices for nanofiber synthesis include rapid prototyping, ease of fabrication, and the ability to spin multiple Janus fibers in parallel through arrays of individual microchannels. Biphasic Janus nanofibers of polyvinylpyrrolidone (PVP)+polypyrrole (PPy)∕PVP nanofibers with an average diameter of 250 nm were successfully fabricated using elastomeric microfluidic devices. Fiber characterization and confirmation of the Janus morphology was subsequently carried out using a combination of scanning electron microscopy, energy dispersion spectroscopy, and transmission electron microscopy. 相似文献
9.
A simple method of fabricating mask-free microfluidic devices for biological analysis 总被引：1，自引：0，他引：1
We report a simple, low-cost, rapid, and mask-free method to fabricate two-dimensional (2D) and three-dimensional (3D) microfluidic chip for biological analysis researches. In this fabrication process, a laser system is used to cut through paper to form intricate patterns and differently configured channels for specific purposes. Bonded with cyanoacrylate-based resin, the prepared paper sheet is sandwiched between glass slides (hydrophilic) or polymer-based plates (hydrophobic) to obtain a multilayer structure. In order to examine the chip’s biocompatibility and applicability, protein concentration was measured while DNA capillary electrophoresis was carried out, and both of them show positive results. With the utilization of direct laser cutting and one-step gas-sacrificing techniques, the whole fabrication processes for complicated 2D and 3D microfluidic devices are shorten into several minutes which make it a good alternative of poly(dimethylsiloxane) microfluidic chips used in biological analysis researches. 相似文献
10.
This review article presents how microfluidic technologies and biological materials are paired to assist in the development of low cost, green energy fuel cell systems. Miniaturized biological fuel cells, employing enzymes or microorganisms as biocatalysts in an environmentally benign configuration, can become an attractive candidate for small-scale power source applications such as biological sensors, implantable medical devices, and portable electronics. State-of-the-art biofuel cell technologies are reviewed with emphasis on microfabrication compatibility and microfluidic fuel cell designs. Integrated microfluidic biofuel cell prototypes are examined with comparisons of their performance achievements and fabrication methods. The technical challenges for further developments and the potential research opportunities for practical cell designs are discussed. 相似文献
11.
This paper describes the main protocols that are used for fabricating microfluidic devices from glass and silicon. Methods for micropatterning glass and silicon are surveyed, and their limitations are discussed. Bonding methods that can be used for joining these materials are summarized and key process parameters are indicated. The paper also outlines techniques for forming electrical connections between microfluidic devices and external circuits. A framework is proposed for the synthesis of a complete glass/silicon device fabrication flow. 相似文献
12.
In this paper, we review the recent progress in the development of low-cost microfluidic devices based on multifilament threads and textiles for semi-quantitative diagnostic and environmental assays. Hydrophilic multifilament threads are capable of transporting aqueous and non-aqueous fluids via capillary action and possess desirable properties for building fluid transport pathways in microfluidic devices. Thread can be sewn onto various support materials to form fluid transport channels without the need for the patterned hydrophobic barriers essential for paper-based microfluidic devices. Thread can also be used to manufacture fabrics which can be patterned to achieve suitable hydrophilic-hydrophobic contrast, creating hydrophilic channels which allow the control of fluids flow. Furthermore, well established textile patterning methods and combination of hydrophilic and hydrophobic threads can be applied to fabricate low-cost microfluidic devices that meet the low-cost and low-volume requirements. In this paper, we review the current limitations and shortcomings of multifilament thread and textile-based microfluidics, and the research efforts to date on the development of fluid flow control concepts and fabrication methods. We also present a summary of different methods for modelling the fluid capillary flow in microfluidic thread and textile-based systems. Finally, we summarized the published works of thread surface treatment methods and the potential of combining multifilament thread with other materials to construct devices with greater functionality. We believe these will be important research focuses of thread- and textile-based microfluidics in future. 相似文献
13.
Mohammad M. N. Esfahani Mark D. Tarn Tahmina A. Choudhury Laura C. Hewitt Ashley J. Mayo Theodore A. Rubin Mathew R. Waller Martin G. Christensen Amy Dawson Nicole Pamme 《Biomicrofluidics》2016,10(1)
The ability to engage and inspire younger generations in novel areas of science is important for bringing new researchers into a burgeoning field, such as lab-on-a-chip. We recently held a lab-on-a-chip workshop for secondary school students, for which we developed a number of hands-on activities that explained various aspects of microfluidic technology, including fabrication (milling and moulding of microfluidic devices, and wax printing of microfluidic paper-based analytical devices, so-called μPADs), flow regimes (gradient formation via diffusive mixing), and applications (tissue analysis and μPADs). Questionnaires completed by the students indicated that they found the workshop both interesting and informative, with all activities proving successful, while providing feedback that could be incorporated into later iterations of the event. 相似文献
14.
In this work, we introduce a method for the soft-lithography-based fabrication of rigid microstructures and a new, simple bonding technique for use as a continuous-flow cell lysis device. While on-chip cell lysis techniques have been reported previously, these techniques generally require a long on-chip residence time, and thus cannot be performed in a rapid, continuous-flow manner. Microstructured microfluidic devices can perform mechanical lysis of cells, enabling continuous-flow lysis; however, rigid silicon-based devices require complex and expensive fabrication of each device, while polydimethylsiloxane (PMDS), the most common material used for soft lithography fabrication, is not rigid and expands under the pressures required, resulting in poor lysis performance. Here, we demonstrate the fabrication of microfluidic microstructures from off-stoichiometry thiol-ene (OSTE) polymer using soft-lithography replica molding combined with a post-assembly cure for easy bonding. With finite element simulations, we show that the rigid microstructures generate an energy dissipation rate of nearly 107, which is sufficient for continuous-flow cell lysis. Correspondingly, with the OSTE device we achieve lysis of highly deformable MDA-MB-231 breast cancer cells at a rate of 85%, while a comparable PDMS device leads to a lysis rate of only 40%. 相似文献
15.
Paul D Saias L Pedinotti JC Chabert M Magnifico S Pallandre A De Lambert B Houdayer C Brugg B Peyrin JM Viovy JL 《Biomicrofluidics》2011,5(2):24102
A broad range of microfluidic applications, ranging from cell culture to protein crystallization, requires multilevel devices with different heights and feature sizes (from micrometers to millimeters). While state-of-the-art direct-writing techniques have been developed for creating complex three-dimensional shapes, replication molding from a multilevel template is still the preferred method for fast prototyping of microfluidic devices in the laboratory. Here, we report on a "dry and wet hybrid" technique to fabricate multilevel replication molds by combining SU-8 lithography with a dry film resist (Ordyl). We show that the two lithography protocols are chemically compatible with each other. Finally, we demonstrate the hybrid technique in two different microfluidic applications: (1) a neuron culture device with compartmentalization of different elements of a neuron and (2) a two-phase (gas-liquid) global micromixer for fast mixing of a small amount of a viscous liquid into a larger volume of a less viscous liquid. 相似文献
16.
The development of widely applicable point-of-care sensing and diagnostic devices can benefit from simple and inexpensive fabrication techniques that expedite the design, testing, and implementation of lab-on-a-chip devices. In particular, electrodes integrated within microfluidic devices enable the use of electrochemical techniques for the label-free detection of relevant analytes. This work presents a novel, simple, and cost-effective bench-top approach for the integration of high surface area three-dimensional structured electrodes fabricated on polystyrene (PS) within poly(dimethylsiloxane) (PDMS)-based microfluidics. Optimization of PS-PDMS bonding results in integrated devices that perform well under pressure and fluidic flow stress. Furthermore, the fabrication and bonding processes are shown to have no effect on sensing electrode performance. Finally, the on-chip sensing capabilities of a three-electrode electrochemical cell are demonstrated with a model redox compound, where the high surface area structured electrodes exhibit ultra-high sensitivity. We propose that the developed approach can significantly expedite and reduce the cost of fabrication of sensing devices where arrays of functionalized electrodes can be used for point-of-care analysis and diagnostics. 相似文献
17.
Paper-based microfluidics are an increasingly popular alternative to devices with conventional open channel geometries. The low cost of fabrication and the absence of external instrumentation needed to drive paper microchannels make them especially well suited for medical diagnostics in resource-limited settings. Despite the advantages of paper microfluidics, many assays performed using conventional open channel microfluidics are challenging to translate onto paper, such as bead, emulsion, and cell-based assays. To overcome this challenge, we have developed a hybrid open-channel/paper channel microfluidic device. In this design, wick-driven paper channels control the flow rates within conventional microfluidics. We fabricate these hybrid chips using laser-micromachined polymer sheets and filter paper. In contrast to previous efforts that utilized external, macroscopic paper-based pumps, we integrated micro-scale paper and open channels onto a single chip to control multiple open channels and control complex laminar flow-pattern within individual channels. We demonstrated that flow patterns within the open channels can be quantitatively controlled by modulating the geometry of the paper channels, and that these flow rates agree with Darcy''s law. The utility of these hybrid chips, for applications such as bead-, cell-, or emulsion-based assays, was demonstrated by constructing a hybrid chip that hydrodynamically focused micrometer-sized polystyrene beads stably for >10 min, as well as cells, without external instrumentation to drive fluid flow. 相似文献
18.
Francesca Sapuppo Andreu Llobera Florinda Schembri Marcos Intaglietta Victor J. Cadarso Maide Bucolo 《Biomicrofluidics》2010,4(2)
We describe design and miniaturization of a polymeric optical interface for flow monitoring in biomicrofluidics applications based on polydimethylsiloxane technology, providing optical transparency and compatibility with biological tissues. Design and ray tracing simulation are presented as well as device realization and optical analysis of flow dynamics in microscopic blood vessels. Optics characterization of this polymeric microinterface in dynamic experimental conditions provides a proof of concept for the application of the device to two-phase flow monitoring in both in vitro experiments and in vivo microcirculation investigations. This technology supports the study of in vitro and in vivo microfluidic systems. It yields simultaneous optical measurements, allowing for continuous monitoring of flow. This development, integrating a well-known and widely used optical flow monitoring systems, provides a disposable interface between live mammalian tissues and microfluidic devices making them accessible to detection∕processing technology, in support or replacing standard intravital microscopy. 相似文献
19.
M. Tijero R. Díez-Ahedo F. Benito-Lopez L. Basabe-Desmonts V. Castro-López A. Valero 《Biomicrofluidics》2015,9(4)
This paper reports an innovative technique for reagents storage in microfluidic devices by means of a one-step UV-photoprintable ionogel-based microarray on non-modified polymeric substrates. Although the ionogel and the ink-jet printing technology are well published, this is the first study where both are used for long-term reagent storage in lab-on-a-chip devices. This technology for reagent storage is perfectly compatible with mass production fabrication processes since pre-treatment of the device substrate is not necessary and inkjet printing allows for an efficient reagent deposition process. The functionality of this microarray is demonstrated by testing the release of biotin-647 after being stored for 1 month at room temperature. Analysis of the fluorescence of the ionogel-based microarray that contains biotin-647 demonstrated that 90% of the biotin-647 present was released from the ionogel-based microarray after pumping PBS 0.1% Tween at 37 °C. Moreover, the activity of biotin-647 after being released from the ionogel-based microarray was investigated trough the binding capability of this biotin to a microcontact printed chip surface with avidin. These findings pave the way for a novel, one-step, cheap and mass production on-chip reagents storage method applicable to other reagents such as antibodies and proteins and enzymes. 相似文献
20.
Reginald Tran Byungwook Ahn David R. Myers Yongzhi Qiu Yumiko Sakurai Robert Moot Emma Mihevc H. Trent Spencer Christopher Doering Wilbur A. Lam 《Biomicrofluidics》2014,8(4)
Cell culture in microfluidic systems has primarily been conducted in devices comprised of polydimethylsiloxane (PDMS) or other elastomers. As polystyrene (PS) is the most characterized and commonly used substrate material for cell culture, microfluidic cell culture would ideally be conducted in PS-based microsystems that also enable tight control of perfusion and hydrodynamic conditions, which are especially important for culture of vascular cell types. Here, we report a simple method to prototype perfusable PS microfluidics for endothelial cell culture under flow that can be fabricated using standard lithography and wet laboratory equipment to enable stable perfusion at shear stresses up to 300 dyn/cm2 and pumping pressures up to 26 kPa for at least 100 h. This technique can also be extended to fabricate perfusable hybrid PS-PDMS microfluidics of which one application is for increased efficiency of viral transduction in non-adherent suspension cells by leveraging the high surface area to volume ratio of microfluidics and adhesion molecules that are optimized for PS substrates. These biologically compatible microfluidic devices can be made more accessible to biological-based laboratories through the outsourcing of lithography to various available microfluidic foundries. 相似文献