A5051812540- Microfluidic and Capillary Electrophoresis Applications
- Microfluidic and Bio-sensing Technologies
- 3D Printing in Biomedical Research
- Innovative Microfluidic and Catalytic Techniques Innovation
- Plant Water Relations and Carbon Dynamics
- Pickering emulsions and particle stabilization
- Electrospun Nanofibers in Biomedical Applications
- Advanced Thermodynamics and Statistical Mechanics
- Angiogenesis and VEGF in Cancer
- Fluid Dynamics and Thin Films
- Nanopore and Nanochannel Transport Studies
- Electrohydrodynamics and Fluid Dynamics
- Lattice Boltzmann Simulation Studies
- Nanofabrication and Lithography Techniques
- Irrigation Practices and Water Management
- Material Dynamics and Properties
- Electrowetting and Microfluidic Technologies
- Cancer Cells and Metastasis
- Wound Healing and Treatments
- Analytical Chemistry and Sensors
- Phase Equilibria and Thermodynamics
- Fluid Dynamics and Heat Transfer
- Theoretical and Computational Physics
- Electrostatics and Colloid Interactions
- Plant and Biological Electrophysiology Studies
Cornell University
2015-2024
Université de Bordeaux
2021
Centre National de la Recherche Scientifique
1999-2021
Ithaca College
2011-2016
Center for Nanoscale Science and Technology
2014
Jawaharlal Nehru Centre for Advanced Scientific Research
2014
Rensselaer Polytechnic Institute
2007
MicroVision (United States)
2006
Office of Public Affairs
2006
Harvard University
1999-2005
Microfluidic devices for manipulating fluids are widespread and finding uses in many scientific industrial contexts. Their design often requires unusual geometries the interplay of multiple physical effects such as pressure gradients, electrokinetics, capillarity. These circumstances lead to interesting variants well-studied fluid dynamical problems some new responses. We provide an overview flows microdevices with focus on mixing dispersion, multiphase flows. highlight topics important...
It is difficult to mix solutions in microchannels. Under typical operating conditions, flows these channels are laminar—the spontaneous fluctuations of velocity that tend homogenize fluids turbulent absent, and molecular diffusion across the slow. We present a passive method for mixing streams steady pressure-driven microchannels at low Reynolds number. Using this method, length channel required grows only logarithmically with Péclet number, hydrodynamic dispersion along reduced relative...
This paper describes a simple, versatile method of generating gradients in composition solution or on surfaces using microfluidic systems. is based controlled diffusive mixing species solutions that are flowing laminarly, at low Reynolds number, inside network microchannels. We demonstrate the use this procedure to generate (1) compositions solutions, measured directly by colorimetric assays and (2) topography produced concentration etching reagents, then these etch profiles into substrate....
Microvascular networks support metabolic activity and define microenvironmental conditions within tissues in health pathology. Recapitulation of functional microvascular structures vitro could provide a platform for the study complex vascular phenomena, including angiogenesis thrombosis. We have engineered living three-dimensional tissue scaffolds demonstrated their biofunctionality vitro. describe lithographic technique used to form endothelialized microfluidic vessels native collagen...
This review describes the design and fabrication of microfluidic systems in poly(dimethylsiloxane) (PDMS). PDMS is a soft polymer with attractive physical chemical properties: elasticity, optical transparency, flexible surface chemistry, low permeability to water, electrical conductivity. Soft lithography makes particularly easy. Integration components, interfacing devices user, also convenient simpler than made hard materials. Fabrication both single multilayer straightforward PDMS. Several...
Devices for handling nanoliter quantities of fluids are creating new fabrication challenges and finding applications in biology, chemistry, materials science.
This letter quantifies both experimentally and theoretically the diffusion of low-molecular-weight species across interface between two aqueous solutions in pressure-driven laminar flow microchannels at high Péclet numbers. Confocal fluorescent microscopy was used to visualize a product formed by reaction chemical carried separately solutions. At steady state, width reaction–diffusion zone adjacent wall channel transverse direction scales as one-third power axial distance down (from point...
This paper describes the design and characterization of a small, membraneless redox fuel cell. The smallest channel dimensions cell were 2 mm × 50 μm or 200 μm; was fabricated in poly(dimethylsiloxane) using soft lithography. all-vanadium took advantage laminar flow to obviate need for membrane separate solutions oxidizing reducing components.
This paper describes a prototype of an integrated fluorescence detection system that uses microavalanche photodiode (microAPD) as the photodetector for microfluidic devices fabricated in poly(dimethylsiloxane) (PDMS). The device consisted reusable and disposable was using rapid prototyping. first step procedure fabrication channels PDMS encapsulation multimode optical fiber (100-microm core diameter) PDMS; tip placed next to side wall one channels. used couple light into microchannel...
Through a simple analytical description we quantify how pressure-driven flows over grooved surfaces develop transverse components, which, for shallow grooves, can be modeled with anisotropic effective boundary conditions. Helical recirculation results in channels or capillaries walls. An experimental validation of our model is presented. Our analysis provides workable guide the design 3D patterns regions, e.g., to control position streams cross section channel promote mixing. Potential...
This Letter reports the measurement of electro-osmotic flows (EOF) in microchannels with surface charge patterned on $200\ensuremath{\mu}\mathrm{m}$ scale. We have investigated two classes patterns: (1) Those which varies along a direction perpendicular to electric field used drive EOF; this type pattern generates multidirectional flow field. (2) parallel field; recirculating cellular flow, and thus causes motion both external Measurements these agree well theory limit thin double layers low...
A solid-object printer was used to produce masters for the fabrication of microfluidic devices in poly(dimethylsiloxane) (PDMS). The provides an alternative photolithography applications where features >250 μm are needed. Solid-object printing is capable delivering objects that have dimensions as large 250 × 190 200 mm (x, y, z) with feature sizes can range from 10 cm μm. user designs a device 3-D CAD program, and file by fabricate master directly without need mask. complex structures,...
We report on the incorporation of microfluidic structure within a high-water-content hydrogel [4% (w/v) calcium alginate]. used network to control chemical environment and demonstrated higher rates delivery extraction solutes than was achievable by diffusion alone.
Plants live dangerously, but gracefully. To remain hydrated, they exploit liquid water in the thermodynamically metastable state of negative pressure, similar to a rope under tension. This tension allows them pull out soil and up their leaves. When this breaks, owing cavitation, catch ends keep it from unraveling then bind back together. In parallel, operate second vascular system for circulation metabolites though tissues, time with positive pressures flow that passes leaf root. article, we...
Abstract In leaves, the transpirational flux of water exits veins as liquid and travels toward stomata in both vapor phases before exiting leaf vapor. Yet, whether most evaporation occurs from vascular bundles (perivascular), photosynthetic mesophyll cells, or within vicinity stomatal pore (peristomatal) remains dispute. Here, a one-dimensional model competition between transport is developed perspective nonisothermal coupled heat molecule composite medium airspace cells. An analytical...
The water status of the living tissue in leaves is critical determining plant function and global exchange CO
This paper describes a microfluidic immunoassay that is applicable to the parallel determination of multiple analytes and requires only few microliters sample. assay relies on microchannel network achieves serial dilution analytes; this replaces manual dilutions employed in traditional immunoassays enables analysis simultaneously. The was demonstrated by an concentrations antibodies against HIV viral proteins gp120 gp41 human serum.
This report outlines a general method for the fabrication of immobilized gradients biomolecules on surfaces. utilizes microfluidic network that generates gradient avidin in solution and immobilizes this protein surface glass or poly(dimethylsiloxane) by physical adsorption. The is then translated into biotinylated ligands (e.g., small molecules, oligomers DNA, polysaccharides) using specific interaction between biotin avidin. can also generate certain proteins artificial polymers direct...
This Account reviews two procedures for controlling the flow of fluids in microchannels. The first procedure involves patterning density charge on inner surfaces a channel. These patterns generate recirculating electroosmotic flows presence steady electric field. second topography an surface recirculation cross-section steady, pressure-driven flows. summarizes applications these to mixing and dispersion (band broadening).