Rapid Fabrication of Custom Microfluidic Devices for Research and Educational Applications

Microfluidic devices allow for the manipulation of fluids, particles, cells, micro-sized organs or organisms in channels ranging from the nano to submillimeter scales. A rapid increase in the use of this technology in the biological sciences has prompted a need for methods that are accessible to a wide range of research groups. Current fabrication standards, such as PDMS bonding, require expensive and time consuming lithographic and bonding techniques. A viable alternative is the use of equipment and materials that are easily affordable, require minimal expertise and allow for the rapid iteration of designs. In this work we describe a protocol for designing and producing PET-laminates (PETLs), microfluidic devices that are inexpensive, easy to fabricate, and consume significantly less time to generate than other approaches to microfluidics technology. They consist of thermally bonded film sheets, in which channels and other features are defined using a craft cutter. PETLs solve field-specific technical challenges while dramatically reducing obstacles to adoption. This approach facilitates the accessibility of microfluidics devices in both research and educational settings, providing a reliable platform for new methods of inquiry

Low-Cost Microfabrication Tool Box

Microsystems are key enabling technologies, with applications found in almost every industrial field, including in vitro diagnostic, energy harvesting, automotive, telecommunication, drug screening, etc. Microsystems, such as microsensors and actuators, are typically made up of components below 1000 microns in size that can be manufactured at low unit cost through mass-production. Yet, their development for commercial or educational purposes has typically been limited to specialized laboratories in upper-income countries due to the initial investment costs associated with the microfabrication equipment and processes. However, recent technological advances have enabled the development of low-cost microfabrication tools. In this paper, we describe a range of low-cost approaches and equipment (below £1000), developed or adapted and implemented in our laboratories. We describe processes including photolithography, micromilling, 3D printing, xurography and screen-printing used for the microfabrication of structural and functional materials. The processes that can be used to shape a range of materials with sub-millimetre feature sizes are demonstrated here in the context of lab-on-chips, but they can be adapted for other applications. We anticipate that this paper, which will enable researchers to build a low-cost microfabrication toolbox in a wide range of settings, will spark a new interest in microsystems

Development of a rapid prototyping method for hard polymer microfluidic systems tested through iterative design of a PCR chamber chip

Tese de mestrado integrado, Engenharia Biomédica e Biofísica (Engenharia Clínica e Instrumentação Médica), Universidade de Lisboa, Faculdade de Ciências, 2014One of the challenges of working with polymer microfluidics is the lack of an established prototyping method which allows for easy translation to industrial production. By combining Hot Embossing and Computer Numerically Controlled Milling a microfluidic rapid prototyping method was established for Polycarbonate and Cyclic Olefin Polymer. This method was then tested and optimized through an iterative design process of a microfluidic Polymerase-Chain Reaction chamber. The fabrication method proved to be suitable for microfluidic prototyping, allowing for rapid design changes and fabrication of good quality copies in a simple and straightforward fashion.Uma das dificuldades em trabalhar com microfluídica em polímeros é a falta da existência de um método de prototipagem que permita uma passagem simples para um ambiente de produção industrial. Neste trabalho foi desenvolvido um método de prototipagem rápida para microfluídica em Policarbonato e Cyclic Olefin Polymer utilizando uma Fresadora de Controlo Numérico Computorizado e Hot Embossing. Este método foi testado e optimizado através de um processo de design iterativo de uma câmara microfluídica de Reacção em Cadeia da Polimerase em Policarbonato. O método desenvolvido provou ser adequado para prototipagem microfluídica, permitindo alterações rápidas ao desenho e fabricação de várias cópias com boa qualidade de cada desenho

Advances in three-dimensional rapid prototyping of microfluidic devices for biological applications

The capability of 3D printing technologies for direct production of complex 3D structures in a single step has recently attracted an ever increasing interest within the field of microfluidics. Recently, ultrafast lasers have also allowed developing new methods for production of internal microfluidic channels within the bulk of glass and polymer materials by direct internal 3D laser writing. This review critically summarizes the latest advances in the production of microfluidic 3D structures by using 3D printing technologies and direct internal 3D laser writing fabrication methods. Current applications of these rapid prototyped microfluidic platforms in biology will be also discussed. These include imaging of cells and living organisms, electrochemical detection of viruses and neurotransmitters, and studies in drug transport and induced-release of adenosine triphosphate from erythrocytes

Low-Cost Microfabrication Tool Box.

Microsystems are key enabling technologies, with applications found in almost every industrial field, including in vitro diagnostic, energy harvesting, automotive, telecommunication, drug screening, etc. Microsystems, such as microsensors and actuators, are typically made up of components below 1000 microns in size that can be manufactured at low unit cost through mass-production. Yet, their development for commercial or educational purposes has typically been limited to specialized laboratories in upper-income countries due to the initial investment costs associated with the microfabrication equipment and processes. However, recent technological advances have enabled the development of low-cost microfabrication tools. In this paper, we describe a range of low-cost approaches and equipment (below £1000), developed or adapted and implemented in our laboratories. We describe processes including photolithography, micromilling, 3D printing, xurography and screen-printing used for the microfabrication of structural and functional materials. The processes that can be used to shape a range of materials with sub-millimetre feature sizes are demonstrated here in the context of lab-on-chips, but they can be adapted for other applications. We anticipate that this paper, which will enable researchers to build a low-cost microfabrication toolbox in a wide range of settings, will spark a new interest in microsystems

Non-conventional solutions to physical and engineering problems facing microfluidics

Microfluidics is a vital tool for scientific research utilising micrometre scale features to provide unparalleled control of micro-, nano- and pico-litres of fluid. Planar lithographic design and fabrication techniques have become more versatile and refined over time. However, stagnation of novel designs, fabrication methodologies and experimental conditions is increasing due to the current limitations. 3D printing is approaching the resolution required in microfluidics, whilst also providing greater freedom of design, materials, and fabrication techniques. This thesis seeks to overcome the traditional limitations using 3D printing to innovate design and production, enabling rapid prototyping methodologies and truly 3D structures, which are typically expensive and labour intensive. The first system discussed within this work generates cells-laden gelatin microdroplets and featured heating and cooling water channels, with a performance comparative to commercial devices. Secondly, a flow cell for the screening of extracellular lectins via glycomimetic liposomes was produced. Additionally, stereolithographic printing was used to produce a bioinspired monolithic droplet generator which featured intertwined channels. Finally, a Van de Graaff generator-based electrophoresis system was developed in order to generate record breaking separation resolutions whilst extended capillary lifespan compared to other experimental systems.Die Mikrofluidik ist ein wichtiges Werkzeug für die wissenschaftliche Forschung, das Merkmale im Mikrometerbereich nutzt, um eine beispiellose Kontrolle von Mikro-, Nano- und Pikolitern von Flüssigkeiten zu ermöglichen. Planare lithografische Konstruktions- und Herstellungstechniken sind im Laufe der Zeit vielseitiger und verfeinert worden. Aufgrund der derzeitigen Einschränkungen nimmt jedoch die Stagnation neuartiger Designs, Herstellungsmethoden und experimenteller Bedingungen zu. Der 3D-Druck nähert sich der in der Mikrofluidik erforderlichen Auflösung und bietet gleichzeitig eine größere Freiheit bei Design, Materialien und Herstellungstechniken. Diese Dissertation versucht, die traditionellen Einschränkungen bei der Verwendung von 3D-Druck zu überwinden, um Design und Produktion zu erneuern und schnelle Prototyping-Methoden und echte 3D-Strukturen zu ermöglichen, die normalerweise teuer und arbeitsintensiv sind. Das erste in dieser Arbeit diskutierte System erzeugt mit Zellen beladene Gelatine-Mikrotröpfchen und verfügt über Heiz- und Kühlwasserkanäle mit einer Leistung, die mit kommerziellen Geräten vergleichbar ist. Zweitens wurde eine Durchflusszelle für das Screening von extrazellulären Lektinen über glykomimetische Liposomen hergestellt. Darüber hinaus wurde stereolithografischer Druck verwendet, um einen bioinspirierten monolithischen Tröpfchengenerator herzustellen, der ineinander verschlungene Kanäle aufweist. Schließlich wurde ein auf einem Van-de-Graaff-Generator basierendes Elektrophoresesystem entwickelt, um rekordverdächtige Trennauflösungen zu erzeugen und gleichzeitig die Kapillarlebensdauer im Vergleich zu anderen experimentellen Systemen zu verlängern

The Role of Micro fluidic Systems in Biological and Medical Sciences

Micro fluidics is a young discipline. During its beginning, it was mainly an academic field in where researchers study the behavior of fluids at micro scale and how it can be modified with operative and experimental variables. Then, the focus was placed on studying device fabrication process and how to optimize them to lower costs and time, and to enhance system features. After a period of maturation, micro fluidic researchers began to evaluate system usefulness and the possibility of use them in different areas. Micro fluidics became a multidisciplinary field combining concepts of biological and medical sciences and engineering. Diagnostic test, micro particles fabrications, contaminant detection, and medical analyses were first goals. Then, its uses expanded exponentially to other areas opening a world of possibilities. With the advances in miniaturization and material sciences as well as the boom in micro and nanotechnology, manufacturing process became highly precise. New applications in biochemistry, biotechnology, biology and medical sciences were appearing attracting the interest of the industrial sector. Since then, projects are aimed to develop micro fluidic systems with industrial applications. The present contribution describes the characteristics of the three major type of micro fluidic systems, chip-based, capillary-based and paper-based systems. Advantages and limitations of each one are mentioned. In addition, their most important applications in biological and medical sciences are presented.Fil: Helbling, Ignacio Marcelo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Desarrollo Tecnológico Para la Industria Química. Universidad Nacional del Litoral. Instituto de Desarrollo Tecnológico Para la Industria Química; ArgentinaFil: Luna, Julio Alberto. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Desarrollo Tecnológico Para la Industria Química. Universidad Nacional del Litoral. Instituto de Desarrollo Tecnológico Para la Industria Química; Argentin

Paper and Fiber-Based Bio-Diagnostic Platforms: Current Challenges and Future Needs

In this perspective article, some of the latest paper and fiber-based bio-analytical platforms are summarized, along with their fabrication strategies, the processing behind the product development, and the embedded systems in which paper or fiber materials were integrated. The article also reviews bio-recognition applications of paper/fiber-based devices, the detected analytes of interest, applied detection techniques, the related evaluation parameters, the type and duration of the assays, as well as the advantages and disadvantages of each technique. Moreover, some of the existing challenges of utilizing paper and/or fiber materials are discussed. These include control over the physical characteristics (porosity, permeability, wettability) and the chemical properties (surface functionality) of paper/fiber materials are discussed. Other aspects of the review focus on shelf life, the multi-functionality of the platforms, readout strategies, and other challenges that have to be addressed in order to obtain reliable detection outcomes. Keywords: paper-based bio-analytical devices; shelf life; equipment-free bio-recognition; flow rate; readout strategies; multi-functional platform

A monolithic continuous-flow microanalyzer with amperometric detection based on the green tape technology

The development of micro total analysis systems (muTAS) has become a growing research field. Devices that include not only the fluidics and the detection system but also the associated electronics are reported scarcely in the literature because of the complexity and the cost involved for their monolithic integration. Frequently, dedicated devices aimed at solving specific analytical problems are needed. In these cases, low-volume production processes are a better alternative to mass production technologies such as silicon and glass. In this work, the design, fabrication, and evaluation of a continuous-flow amperometric microanalyzer based on the green tape technology is presented. The device includes the microfluidics, a complete amperometric detection system, and the associated electronics. The operational lifetime of the working electrode constitutes a major weak point in electrochemical detection systems, especially when it is integrated in monolithic analytical devices. To increase the overall system reliability and its versatility, it was integrated following an exchangeable configuration. Using this approach, working electrodes can be readily exchanged, according to the analyte to be determined or when their surfaces become passivated or poisoned. Furthermore, the electronics of the system allow applying different voltamperometric techniques and provide four operational working ranges (125, 12.5, 1.25, and 0.375 muA) to do precise determinations at different levels of current intensity.The authors would like to thank the Spanish MEC for its financial support through: Consolider-Ingenio 2010 (CSD2006-00012), TEC2006-13907-C04-04/MIC and CIT- 310200-2007-29