Charles Henry (Colorado State University, USA)
Title: Advances in Paper-Based and 3D Printed Microfluidics
Abstract: There is a continuing interest in the development of low-cost fabrication methods and materials to create microfluidic devices for applications ranging from point-of-care monitoring to in vitro studies of disease biology. Two newer methods and materials for fabricating devices include paper-based microfluidics and 3D printed devices. This talk will discuss novel aspects of both types of microfluidic devices. Paper-based analytic devices have been used for centuries but a renewed interest in the substrate as a material for microfluidics started a decade ago when patterned paper was used to carry out multiplexed chemical analysis of urine samples. Since that time, the field has exploded in methods for fabrication, methods for detection, and applications. Our group has used paper-based devices for both environmental and clinical diagnostics with an emphasis on building devices that can be used in the field. To this end, recent results focused on detecting bacteria, including anti-microbial resistant bacteria, will be presented. We have shown that chemistry can be developed with a range of selectivity from very specific (immunoassay and DNA-based) to general (enzyme-based). Use of the system to detect antimicrobial resistance in surface water will also be presented as an effort towards understanding horizontal transfer of resistance within the environment. While paper-based devices have utility for point of care measurements, there is also interest in developing microfluidic devices containing cells to mimic the human body that would enable studies ranging from basic disease biology to drug metabolism. 3D printing offers an excellent tool for prototyping devices using biocompatible materials, however, ease of fabrication and sealing devices with small channels has been a problem. A new approach to fabricating integrated devices with narrow (100 um) channels will be presented along with use of these systems to study the biology of ex vivo tissue slices.
Leslie Yeo (RMIT University, Melbourne, Australia)
Title: Acoustofluidics: Manipulating Fluids at the Microscale and Nanoscale for Biomedical Applications
Abstract: Though uncommon in most microfluidic systems due to the dominance of viscous and capillary stresses, it is possible to induce inertial transport at microscale and nanoscale dimensions using ultrasonic excitation. In particular, microfluidic actuation and manipulation is particularly efficient when driven using MHz order surface acoustic waves (SAWs), which are nanometer order amplitude electroelastic waves that can be generated on a piezoelectric substrate. Due to the confinement of the high frequency acoustic energy to a thin localized region along the substrate surface and its subsequent leakage into the body of liquid with which the substrate comes into contact, SAWs are an extremely efficient mechanism for driving ultrafast microfluidics. We demonstrate that it is possible to generate a variety of efficient microfluidic flows using the SAW. For example, SAWs can be exploited to pump liquids in microchannels or to translate free droplets typically one or two orders of magnitude faster than conventional electroosmotic or electrowetting technology. Moreover, it is possible to drive strong microcentrifugation to induce efficient micromixing and bioparticle concentration/separation. At large input powers, the SAW is also a powerful means for the generation of jets and nebulized aerosol droplets through rapid destabilization of the parent drop interface. For example, slender liquid jets persisting up to centimeters in length can be generated without requiring nozzles or orifices, or alternatively, a monodispersed distribution of 1–5 micron diameter aerosol droplets is obtained, which can be exploited for drug delivery and encapsulation, nanoparticle synthesis, and template-free polymer array patterning. Besides highlighting these and other applications possible with SAW microfluidics, we also uncover the fundamental physical mechanisms responsible for the rich and complex phenomena arising from the highly nonlinear fluid-structural interaction at high MHz frequencies, which include novel colloidal pattern formation, thin film instabilities and capillary wave dynamics.
Marcio S. Carvalho (Departamento de Engenharia Mecânica, PUC-Rio, Rio de Janeiro, RJ, Brasil)
Title: Capillary Hydrodynamics: From thin films to enhanced oil recovery
Abstract: In most applications, multiphase flow behavior in microscale is governed by the balance between capillary and viscous, or viscoelastic in case of polymer solutions, forces. Fundamental understanding of capillary hydrodynamics may lead to important technology development in different areas, including the manufacturing of optical and specialty films, printed electronics, biological sensors, CO2 sequestration and enhance oil recovery.
We discuss two examples of capillary hydrodynamic flows. The first one is related to the manufacturing of functional films by slot coating process. Slot coating is one of the preferred methods to obtain a thin and uniform liquid layer over a moving substrate. The coated film must have a particular microstructure in order to function as designed. In many applications, such as solar panels, printed electronics and batteries, the coating liquid is a suspension of particles. The rheology of these systems may be quite complex and depends on the particle concentration and orientation with respect to the flow. Moreover, particles can migrate driven by different mechanisms leading to a non-uniform particle distribution in the flow. The fundamental understanding of this problem and its impact on the coating process are not well understood. We analyze slot coating flows of particle suspensions, investigating particle distribution and orientation and how process parameters may affect the final structure of the coated layer.
The second example is associated with flows of complex liquids in porous media, with application in oil recovery. A porous media can be thought as a 3D network of constricted micro channels, e.g. a very complex microfluidic device. We study the effect of complex dispersions (oil-water emulsions and soft microcapsules suspensions) and polymer solutions in the pore scale. Visualization of the flow of complex fluids through a transparent network of micro-channels, which serves as a model of a porous media, reveals how the pore blocking by the dispersed phase improves pore-level displacement efficiency, leading to lower residual oil saturation. In the case of soft capsule dispersions, the degree of pore level mobility reduction is controlled by the elastic properties of the capsule shell, which are fabricated using capillary microfluidic devices.
Adriano Mesquita Alencar (Universidade de São Paulo, IFUSP-SP)
Title: Fluid distribution and velocity measurements in leaf venation patterns
Abstract: Several examples of nearly optimal transport networks can be found in nature. These networks effectively distribute and drain fluids throughout a medium. Evidence suggests that blood vessels of the circulatory system, airways in the lungs and veins of leaf venations are examples of networks that have evolved to become effective in their tasks while simultaneously being energetically economical. Hence, it does not come as a surprise that recent improvements in performance of modern devices occur due to the use of nature-inspired channel arquitecures. Guided by this observations, in this work, we investigate the application of visually realistic computer-generated leaf venation patterns to a power generating device. We solve the flow the through the device using Computational Fluid Dynamics (CFD) tools. Moreover, we develop an experimental model to compare the results and to study the velocity profile.
Cyro Ketzer Saul (Universidade Federal do Paraná)
Title: Novel method for flow-rate measurement in microsystems
Abstract: With the ongoing demand of Lab-on-Chip shrinkage there is a consequential dimensional reduction need for monitoring and controlling devices. Within this panorama, the measurement of pressure and flow-rate becomes relevant to assess both the system productivity and efficiency. Pressure measurement, mainly using microfabricated membranes is a well established field, with eventual chances for further development. Flow-rate measurement instead, presents some very interesting challenges, mainly when the objective is to measure in short time intervals. Most available flow-rate sensors demand for complex fabrication processes and its measurements are usually associated to bulky data acquisition equipment. In this work, we present a low complexity opto-electrochemical flow-rate measurement device, which can be easily integrated in microfabricated systems. The developed device is quite versatile allowing different range measurement by just changing its dimensional features. All its control and monitoring features were performed using an open source Arduino platform. Further characterization is underway to determine other potential applications.
Murilo Santhiago (DSF-LNNano, Campinas)
Title: Flexible, Foldable, and High-performance Paper-based Electrochemical Devices
Abstract: Paper is as substrate that has innumerous potential to meet some of the recent demands of the industry, including smart packages, filters, envelopes, and a variety of electrochemical sensors and biosensors. Some applications and large-scale fabrication processes requires flexible and foldable devices. Wearable devices, three-dimensional electronics and roll-to- roll fabrication processes are examples of such requirements. In this talk, I will demonstrate different routes to fabricate flexible, foldable, and high performance carbon-based electrochemical sensors on paper. Drawing techniques and fully printed processes that are compatible with the roll-to- roll technology will be demonstrated. The talk will also cover the characterization and the applications of these paper-based electrochemical/electrical devices, such as high-performance electrochemical devices, wearable and motion sensors.
Lucimara Gaziola de la Torre (UNICAMP)
Title: Microfluidics Applied in Nano & Biotecnology
Abstract: Microfluidics can be applied in the fields of nano and biotechnology. In the nanotechnology field, one important application is in gene therapy, which is based on the idea to carry out the treatment of specific diseases through the insertion of a therapeutic nucleic acid to target cells or patients. In this context, microfluidics is promising for the production of liposomes and polymeric nanoparticles (chitosan), exploring diffusion-based processes to synthesize these nanomaterials with low polydispersity. The incorporation of nucleic acids into these nanomaterials can also be explored in microfluidcs, presenting innumerous advantages in comparison to the macroscale. In the field of biotechnology, microfluidics can be a useful tool for the screening of optimal conditions of microbial growth, offering microenvironments with cultivation conditions constant over time. In addition, single cell-analysis can also be developed in microfluidic environment, allowing the investigation of heterogeneities of mammalian cells.
Wendell Karlos Tomazelli Coltro (Universidade Federal de Goiás)
Title: Dispositivos microfluídicos para aplicações em Química Forense e em Bioanalítica
Abstract: A microfluídica tem avançado consideravelmente nos últimos anos permitindo o desenvolvimento de dispositivos analíticos descartáveis para uso no ponto de necessidade. Dentre as diversas aplicações já reportadas na literatura, dispositivos dedicados a estudos bioanalíticos, especialmente em diagnósticos, e em química forense estão ganhando destaque cada vez maior. Na presente apresentação, serão apresentados alguns avanços nessas duas áreas. Na química forense, por exemplo, dispositivos dedicados à detecção de (i) adulterantes em bebidas lácteas e alcóolicas, (ii) resíduos de disparos de armas de fogo, (iii) contaminação em drogas ilícitas, (iv) autencidade de medicamentos e (v) estimativa do interalo de postmortem serão apresentados. Com relação aos estudos em bioanalítica, o desenvolvimento de dispositivos para (i) diagnóstico de dengue, (ii) detecção de amilase em pacientes com quadro de pancreatite, (iii) detecção de espécies nitrogenadas e proteínas totais em fluidos orais serão apresentados. Para todos os exemplos citados, será dado enfoque às plataformas microfluídicas desenvolvidas em substratos diversos incluindo vidro, poli(dimetil siloxano) (PDMS), poliéster-toner e papel bem como a integração com detectores eletroquímicos e colorimétricos.
Antonio Carlos Seabra (USP/POLI)
Title: Microdevices for Water Monitoring: From Lab to Field
Abstract: Field installation of microdevices draws attention to non-functional problems that must be solved prior to correct deployment. This presentation discusses some common problems encountered in the installation of microdevices for continuos monitoring of phosphorus concentration in water reservoirs.
Dolomite Microfluidics – Msc. Max Drobot
Max Drobot obtained his MSc in Chemistry from Montpellier (France) then worked for AstraZeneca and Pfizer as a discovery chemist where he championed the use of flow chemistry for API synthesis in early drug discovery. Max joined the Blacktrace group 7 years ago to work on new application for flowchemistry and oversee the launch of the award winning Syrris Asia flow product range. His interest and responsibilities have since widened to all microfluidic applications and Max is now Head of Products at Blacktrace with a specific focus on Dolomite Microfluidics brand.
Abstract: Dolomite is the world leader in design and manufacture of microfluidic products such as pumps (volumetric, pressure), microchips, connectors, sensors, complete systems and customized products for different kinds of applications (cell encapsulation, nanoparticle synthesis, droplet generation, emulsion generation and double emulsions, droplet scale-up production, among others). In addition to the above mentioned subjects, we will also present our new system “Fluidic Factory” (R & D 100 Awards Winner), which is the world’s first commercially available 3D printer for fast prototyping of fluidically sealed devices (design your own microfluidic devices, manifolds, connectors or select designs from the design library and get printing in minutes!)