TY - JOUR. T1 - Micro-patterning of animal cells on PDMS substrates in the presence of serum without use of adhesion inhibitors. AU - De Silva, Mauris N.. AU - Desai, Ravi. AU - Odde, David J.. N1 - Funding Information: The authors would like to thank Yaakov Nahmias, Abhinav Arneja, and Andrew Bicek for their advice in HUVEC and LLCPK1 cell culture and the staff of the Nano Fabrication Center of the University of Minnesota, Dr. Babak Ziaie, and Tingrui Pan for their advice in fabrication technologies. Funding for this project was partially provided by NSF-BITS Grant No. EIA0130875 and through the Microfabricated Neural Networks Interest Group by the Biomedical Engineering Institute at University of Minnesota.. PY - 2004/9. Y1 - 2004/9. KW - Cell patterning. KW - Microcontact printing. KW - Micropatterning. KW - PDMS. UR - http://www.scopus.com/inward/record.url?scp=4544299869&partnerID=8YFLogxK. UR - http://www.scopus.com/inward/citedby.url?scp=4544299869&partnerID=8YFLogxK. U2 - ...

The goal of this study was the preparation, physicochemical characterization, and microbiological evaluation of novel hydroxyapatite doped with silver/polydimethylsiloxane (Ag:HAp-PDMS) composite layers. In the first stage, the deposition of polydimethylsiloxane (PDMS) polymer layer on commercially pure Si disks has been produced in atmospheric pressure corona discharges. Finally, the new silver doped hydroxyapatite/polydimethylsiloxane composite layer has been obtained by the thermal evaporation technique. The Ag:HAp-PDMS composite layers were characterized by various techniques, such as Scanning Electron Microscopy (SEM), Glow Discharge Optical Emission Spectroscopy (GDOES), and X-ray photoelectron spectroscopy (XPS). The antimicrobial activity of the Ag:HAp-PDMS composite layer was assessed against |i|Candida albicans|/i| ATCC 10231 (ATCC—American Type Culture Collection) by culture based and confirmed by SEM and Confocal Laser Scanning Microscopy (CLSM) methods. This is the first study

Aqueous biocompatible tribosystems are desirable for a variety of tissue-contacting medical devices. L-3,4-dihydroxyphenylalanine (DOPA) and lysine (K) peptide mimics of mussel adhesive proteins strongly interact with surfaces and may be useful for surface attachment of lubricating polymers in tribosystems. Here, we describe a significant improvement in lubrication properties of poly (dimethylsiloxane) (PDMS) surfaces when modified with PEG-DOPA-K. Surfaces were characterized by optical and atomic force microscopy, contact angle, PM-IRRAS, and X-ray photoelectron spectroscopy. Such surfaces, tested over the course of 200 rotations (∼8 m in length), maintained an extremely low friction coefficient (μ) (0.03 ± 0.00) compared to bare PDMS (0.98 ± 0.02). These results indicate the potential applications of PEG-DOPA-K for the modification of device surfaces. Extremely low μ values were maintained over relatively long length scales and a range of sliding speeds without the need for substrate ...

Page contains details about poly(dimethylsiloxane)/graphene/graphene oxide/reduced graphene oxide film . It has composition images, properties, Characterization methods, synthesis, applications and reference articles : nano.nature.com

Maintaining a proper pH level is crucial for successful cell culturing. Mammalian cells are commonly cultured in incubators, where the cell culture medium is saturated with a mixture of air and 5% carbon dioxide (CO,inf,2,/inf,). Therefore, to keep cell culture medium pH in an acceptable level outside these incubators, a suitable CO,inf,2,/inf, concentration must be dissolved in the medium. However, it can be very difficult to control and measure precisely local concentration levels. Furthermore, possible undesired concentration gradients generated during long-term cell culturing are almost impossible to detect. Therefore, we have developed a computational model to estimate CO,inf,2,/inf, transport in silicone-based microfluidic devices. An extensive set of experiments was used to validate the finite element model. The model parameters were obtained using suitable measurement set-ups and the model was validated using a fully functional cell cultivation device. The predictions obtained by the ...

The way in which bacterial communities colonize flow in porous media is of importance but basic knowledge on the dynamic of these phenomena is still missing. The aim of this work is to develop microfluidic experiments in order to progress in the understanding of bacteria capture in filters and membranes. PDMS microfluidic devices mimicking filtration processes have been developed to allow a direct dynamic observation of bacteria across 10 or 20 micrometers width microchannels. When filtered in such devices, bacteria behave surprisingly: Escherichia coli, Pseudomonas aeruginosa or Staphylococcus aureus accumulate in the downstream zone of the filter and form large streamers which oscillate in the flow. In this study streamer formation is put in evidence for bacteria suspension in non nutritive conditions in less than one hour. This result is totally different from the one observed in same system with inert particles or dead bacteria which are captured in the bottleneck zone and are accumulated in the

Highly flexible and transparent strain sensors are fabricated by directly coating super-aligned carbon nanotube (SACNT) films on polydimethylsiloxane (PDMS) substrates. The fabrication process is simple, low cost, and favorable for industrial scalability. The SACNT/PDMS strain sensors present a high sensing

Silicone rubber as used in blood contacting situations usually contains fillers, catalyst and other additives. In this study, polydimethylsiloxane (PDMS) alone was cross-linked by ionizing radiation in a nitrogen atmosphere to produce a pure silicone rubber. This material exhibited a Lee-White clotting time over 45 minutes and a clotting time of 90 minutes when air-blood contact was minimized. Comparable times for commercial silicones are 25 and 60 minutes. In extracorporeal testing using a Mini Lung, an irradiated PDMS coated membrane demonstrated greatly improved thromboresistance over standard silicone rubber membranes. (Author)

Chlorhexidine (CHX) has been incorporated into the composition of polymethyl methacrylate (PMMA) dental restorations to enhance their antimicrobial performance. However, the controlled delivery of CHX remains a challenge. Although previous findings with pure silica or polymer coatings demonstrated the resistance to bacterial adhesion, they did not provide antibacterial activity beyond the coated surface. Polydimethylsiloxane (PDMS) and mesoporous silica nanoparticles (MSNs) are widely used in biomedical science as a transfer medium in drug delivery systems. Here, the MSNs are used to encapsulate CHX, and the combination is added to PDMS. A thin coating film is formed on the PMMA, using oxygen plasma and thermal treatment. The liquid chromatography analysis shows that the coating film has high encapsulation efficiency and loading capacity, with a slow and stable release rate of CHX. The cytotoxicity tests also show that the coating does not affect the proinflammatory cytokines, cellular mitotic activity,

A PED (precision extrusion deposition)/replica molding process enables scaffold guided tissue engineering of a heterocellular microfluidic device. We investigate two types of cell-laden devices: the first with a 3D microfluidic manifold fully embedded in a PDMS (polydimethylsiloxane) substrate and the second a channel network on the surface of the PDMS substrate for cell printing directly into device channels. Fully embedded networks are leak-resistant with simplified construction methods. Channels exposed to the surface are used as mold to hold bioprinted cell-laden matrix for controlled cell placement throughout the network from inlet to outlet. The result is a 3D cell-laden microfluidic device with improved leak-resistance (up to 2.0 mL/min), pervasive diffusion and control of internal architecture.. ...

But what if the product B turned into another product C? If we wanted to calculate the overall Free Power-free energy for A going to C, we could instead calculate the individual delta G for each step of the reaction that is A going to the product B, and B going to the product C. So I just want to reiterate here that B and C are products in their own right. Theyre not transition states. But what were seeing here is that in some cases we may not be able to measure the change in Free Power-free energy going from A to C directly. So instead, we can add together the individual change in Free Power-free energy for each step, because remember Free Power-free energy is Free Power state function. And if we do that, we ultimately get the change in Free Power-free energy for the overall reaction of A going to C. Now one fun way that I kind of remember the state function like quality of delta G, as well as some other variables in chemistry, is that my chemistry professor used to tell us that life is not ...

But what if the product B turned into another product C? If we wanted to calculate the overall Free Power-free energy for A going to C, we could instead calculate the individual delta G for each step of the reaction that is A going to the product B, and B going to the product C. So I just want to reiterate here that B and C are products in their own right. Theyre not transition states. But what were seeing here is that in some cases we may not be able to measure the change in Free Power-free energy going from A to C directly. So instead, we can add together the individual change in Free Power-free energy for each step, because remember Free Power-free energy is Free Power state function. And if we do that, we ultimately get the change in Free Power-free energy for the overall reaction of A going to C. Now one fun way that I kind of remember the state function like quality of delta G, as well as some other variables in chemistry, is that my chemistry professor used to tell us that life is not ...

This work describes the centrifugal casting and fast curing of double-sided, polydimethylsiloxane (PDMS)-based components with microfeatures. Centrifugal casting permits simultaneous patterning of multiple sides of a component and allows control of the thickness of the part in an enclosed mold without entrapment of bubbles. Spinning molds filled with PDMS at thousands of revolutions per minute for several minutes causes entrapped bubbles within the PDMS to migrate toward the axis of rotation or dissolve into solution. To cure the parts quickly (,10 min), active elements heat and cool cavities filled with PDMS after the completion of spinning. Microfluidic channels produced from the process have a low coefficient of variation (,2% for the height and width of channels measured in 20 parts). This process is also capable of molding functional channels in opposite sides of a part as demonstrated through a device with a system of valves typical to multilayer soft lithography.. ...

TY - JOUR. T1 - Axisymmetric polydimethysiloxane microchannels for in vitro hemodynamic studies. AU - Lima, Rui. AU - Oliveira, Monica. AU - Ishikawa, T.. AU - Kaji, H.. AU - Tanaka, S.. AU - Nishizawa, M.. AU - Yamaguchi, T. PY - 2009/9. Y1 - 2009/9. N2 - The current microdevices used for biomedical research are often manufactured using microelectromechanical systems (MEMS) technology. Although it is possible to fabricate precise and reproducible rectangular microchannels using soft lithography techniques, this kind of geometry may not reflect the actual physiology of the microcirculation. Here, we present a simple method to fabricate circular polydimethysiloxane (PDMS) microchannels aiming to mimic an in vivo microvascular environment and suitable for state-of-the-art microscale flow visualization techniques, such as confocal µPIV/PTV. By using a confocal µPTV system individual red blood cells (RBCs) were successfully tracked trough a 75 µm circular PDMS microchannel. The results show that ...

This experiment was adapted by John Kania from one developed by Michael Davis, Microcontact Printing on Gold CD-Rs. PDMS is cured by an organometallic crosslinking reaction to give an optically transparent polymer with the ability to reproduce surface features. In the experiment the polymer is cured in contact with a coin or the printed side…

The first step in microcontact printing is the production of an elastomeric malleable stamp by means of a mold. The stamp is then loaded with a special ink and is pressed onto the metal surface to be printed. The ink sticks to the metal surface and reproduces the microstructure of the stamp in a monomolecular layer. This monolayer acts as a corrosion-resistant mask in the subsequent etching process: the coated areas are not affected, whereas the metal in the uncoated areas is etched away, transferring the microstructure to the metal. Precious and coinage metals are both used, as are materials with oxidic surfaces, such as silicon and aluminum. Each type of surface requires a different type of ink to stick to it: precious and coinage metals need ink molecules that can be bound by means of a metal-sulfur bond. Oxidic surfaces bind molecules with an acid functionality, such as carboxylic acids or phosphonic acids. Substrates that have different types of metals on their surface are thus not easy ...

Nanopoint has developed a novel micro-fabricated live cell containment device called cellTRAYTM designed specifically for imaging live cells. The device enables the precise containment of cells in an optical glass substrate, the size of a standard 1

Nanopoint has developed a novel micro-fabricated live cell containment device called cellTRAYTM designed specifically for imaging live cells. The device enables the precise containment of cells in an optical glass substrate, the size of a standard 1

A living cell has numerous proteins, only a few thousand of which have been identified to date. Cell-free protein synthesis is a useful and promising technique to discover and produce various proteins that might be beneficial for biotechnological, pharmaceutical, and medical applications. For this study, we evaluated the performance and the general applicability of our previously developed microreactor array chip to cell-free protein synthesis by comparisons with a commercially available system. The microreactor array chip comprises a temperature control chip made of glass and a disposable reaction chamber chip made of polydimethylsiloxane (PDMS). For evaluation of the microreactor array chip, rat adipose-type fatty acid binding protein, glyceraldehyde-3-phosphate dehydrogenase, cyclophilin, and firefly luciferase were synthesized from their respective DNA templates using a cell-free extract prepared from ,i,Escherichia coli,/i,. All these proteins were synthesized in the microreactor array ...

A microfluidic device, with a temperature control unit to study the behaviour of temperature sensitive hydrogel, has been designed, simulated and fabricated. The system consists of a PDMS (polydimethylsiloxane) microchannel sealed on a Pyrex substrate with microfabricated titanium electrodes for heating and sensing elements. A thermal insulating layer in-between the electrodes and the substrate was found to increase the heat transfer to the fluid and decrease the lateral heat propagation. The temperature profile and the heat distribution in the system were investigated using the commercial software package CFD-ACE+. The device was electrically and thermally characterised. Such a system, biocompatible and re-usable, could be a potential candidate for biomedical applications such as DNA amplification and protein synthesis ...

The interactions between a cancer cell and its extracellular matrix (ECM) have been the focus of an increasing amount of investigation. The role of the intermediate filament keratin in cancer has also been coming into focus of late, but more research is needed to understand how this piece fits in the puzzle of cytoskeleton-mediated invasion and metastasis. In Panc-1 invasive pancreatic cancer cells, keratin phosphorylation in conjunction with actin inhibition was found to be sufficient to reduce cell area below either treatment alone. We then analyzed intersecting keratin and actin fibers in the cytoskeleton of cyclically stretched cells and found no directional correlation. The role of keratin organization in Panc-1 cellular morphological adaptation and directed migration was then analyzed by culturing cells on cyclically stretched polydimethylsiloxane (PDMS) substrates, nanoscale grates, and rigid pillars. In general, the reorganization of the keratin cytoskeleton allows the cell to become ...

The interactions between a cancer cell and its extracellular matrix (ECM) have been the focus of an increasing amount of investigation. The role of the intermediate filament keratin in cancer has also been coming into focus of late, but more research is needed to understand how this piece fits in the puzzle of cytoskeleton-mediated invasion and metastasis. In Panc-1 invasive pancreatic cancer cells, keratin phosphorylation in conjunction with actin inhibition was found to be sufficient to reduce cell area below either treatment alone. We then analyzed intersecting keratin and actin fibers in the cytoskeleton of cyclically stretched cells and found no directional correlation. The role of keratin organization in Panc-1 cellular morphological adaptation and directed migration was then analyzed by culturing cells on cyclically stretched polydimethylsiloxane (PDMS) substrates, nanoscale grates, and rigid pillars. In general, the reorganization of the keratin cytoskeleton allows the cell to become ...

Thermosensitive polymers are a class of smart materials that have the ability to respond to a change in temperature. SPECIFIC POLYMERS synthesize a broad array of monomers and polymers of interest in this area ...

The mechanical properties of polymeric nanocomposites are strongly affected by the nature of the interphase between filler and matrix, which can be controlled by means of surface chemistry. In this report, we utilize intermodulation atomic force microscopy (ImAFM) to probe local mechanical response with nanometer-scale resolution of poly(dimethylsiloxane) (PDMS),coatings with and without 20 wt of hydrophobic silica nanoparticles. The data evaluation is carried out without inferring any contact mechanics model, and is thus model-independent. ImAFM imaging reveals a small but readily measurable inhomogeneous mechanical response of the pure PDMS surface layer. The analysis of energy dissipation measured with ImAFM showed a lowering of the viscous response due to the presence of the hydrophobic silica nanoparticles in the polymer matrix. An enhanced elastic response was also evident from the in-phase stiffness of the matrix, which was found to increase by a factor of 1.5 in presence of the ...

Abstract: Microfluidic systems integrated with protein and DNA micro- and nanoarrays have been the most sought-after technologies to satisfy the growing demand for high-throughput disease diagnostics. As the sensitivity of these systems relies on the bio-functionalities of the patterned recognition biomolecules, the pr

A microactuator device includes a base with at least one electrode pad and a permeation membrane. Permeation membrane is typically a water-permeable membrane that is able to deform by applying an electric charge to the electrode pad. The actuator device can be incorporated into valve assembly to open and close the valve. The valve assembly can have a reciprocating valve member operated by the deforming of the water-permeable member. Alternatively, the valve assembly can have an opening positioned to cooperate with the water-permeable membrane so that the deformation of the membrane closes the opening.

Recent experimental data dealing with gas-liquid two-phase flow regimes and their transitions in microchannels with circular and near-circular cross-sections are reviewed and compared. It is shown that, for microchannels with hydraulic diameters close to 1 mm, the available data are in good agreement. These data are used as the basis for the development of a simple Weber number-based flow regime map that divides the entire flow map into four zones: a surface tension dominated zone including bubbly and plug flow patterns; an inertia dominated zone representing the annular flow regime; a dispersed/churn flow zone; and a transition zone that consists of other intermittent flow patterns. Comparison is als o made with the limited available data representing channels with slightly larger hydraulic diameters or different cross-sectional geometries, and the effects of channel cross-sectional geometry and size are examined and discussed. The areas in need of further systematic experimental investigation ...

Looking for microfabrication? Find out information about microfabrication. The technology of fabricating microsystems from silicon wafers, using standard semiconductor process technologies in combination with specially developed... Explanation of microfabrication

Solute transport in porous media has always been a focus topic for hydrogeologists. Hydrodynamic dispersion is one of the most important mechanism in solute transport in porous media. Furthermore, dispersion behaviors vary substantially under different saturations. Recent research has introduced fluorescence microscopy methods such as fluorescence recovery after photobleaching (FRAP) ... read more to investigate solute dispersion problem due to its noninvasive nature creating concentration input inside porous medium. In this study, a fluorescence microscopy setup is developed to conduct dispersion experiments in Polydimethylsiloxane (PDMS) microfluidic models. For saturated condition, various dispersion experiments under different flow rates and porosities are conducted. Subsequently, based on the results, a nonlinear negative longitudinal dispersivity-porosity relationship is drawn. Under unsaturated condition, by utilizing the decay nature of the fluorescent molecule, distinction between ...

Conjugated polyelectrolytes (CP) show interesting electrical and optical properties for organic electronics as well as for life science applications. Their possibilities of supramolecular assembly with nanowire like misfolded proteins, amyloids, as well as synthetic polypeptides or DNA forming conducting or luminescent nano composites is highly interesting as being a truly bottom up approach for fabrication of OLEDs, photovoltaics as well as logic devices. The conformation and aggregation dependent luminescence properties from the special class of CPs, Luminescent conjugated polyelectrolytes (LCP), have been utilised and developed as sensors to follow and study biomolecular interactions, DNA hybridisation, protein-protein interactions and staining of living cell cultures and tissue slides. In this thesis we are bringing the evolution a few steps further by applying new types of experimental techniques, such as light scattering and fluorescence correlation spectroscopy, combined with standard ...

TY - JOUR. T1 - Adhesion and migration of cells responding to microtopography. AU - Estévez, Maruxa. AU - Martínez, Elena. AU - Yarwood, Stephen J. AU - Dalby, Matthew J.. AU - Samitier, Josep. N1 - © 2014 Wiley Periodicals, Inc.. PY - 2015/5. Y1 - 2015/5. N2 - It is known that cells respond strongly to microtopography. However, cellular mechanisms of response are unclear. Here, we study wild-type fibroblasts responding to 25 µm(2) posts and compare their response to that of FAK(-/-) fibroblasts and fibroblasts with PMA treatment to stimulate protein kinase C (PKC) and the small g-protein Rac. FAK knockout cells modulated adhesion number and size in a similar way to cells on topography; that is, they used more, smaller adhesions, but migration was almost completely stalled demonstrating the importance of FAK signaling in contact guidance and adhesion turnover. Little similarity, however, was observed to PKC stimulated cells and cells on the topography. Interestingly, with PKC stimulation the ...

This report describes the fabrication and characterization of a simple and disposable capillary isoelectric focusing (cIEF) device containing a reagent-release capillary (RRC) array and poly(dimethylsiloxane) (PDMS) platform, which allows rapid (within 10 min) screening of cIEF conditions by introducing a sa 10th Anniversary Issue: Japan

Cancer tumor cells exist within a mechanically and heterogeneous microenvironment which undergoes active adjustments throughout neoplastic development chemically. suggest that elevated matrix rigidity and collagen thickness promote improved grip causes, and that metastatic cells generate higher causes AP24534 enzyme inhibitor than non-metastatic cells across all matrix properties examined. Additionally, we discovered that cell dispersing for these cell lines includes a immediate romantic relationship with collagen thickness, but a biphasic romantic relationship with substrate rigidity, indicating that cell region alone will not dictate the magnitude of grip stress AP24534 enzyme inhibitor generation. Jointly, these data claim that mobile contractile drive may play a significant function in metastasis, which the physical properties from the stromal environment may regulate cellular force era. These results are crucial for understanding the physical systems of metastasis as well as the role from ...

Local surface mechanical properties of polymeric nanocomposites play a significant role in theirperformance. Atomic Force Microscopy (AFM) can be used to perform measurements of suchproperties with high lateral resolution. The interphase between filler and matrix, and how it can becontrolled by means of surface chemistry is of particular interest. In this work we compare threeoperating modes of AFM: Tapping mode, PeakForce QNM (Quantitative Nanomechanical Mapping)and Intermodulation AFM (ImAFM), for their ability to capture the tip-surface force and to extractlocal mechanical properties by applying different contact mechanics models. Layers ofpoly(dimethylsiloxane) (PDMS) with and without 20 wt.% of hydrophobic silica nanoparticles werestudied employing these AFM modes. We show that tapping mode AFM can provide qualitativeinformation, but it is insufficient to accurately and quantitatively discriminate surface propertiessince this mode does not allow extraction of the tip-surface force. ...

The overuse and misuse of antibiotics have resulted in the emergence of antibiotic-resistant pathogens along with the perturbation of healthy human microbiota via killing putatively beneficial commensal bacteria. Hence, targeting infectious bacterial pathogens is important for reducing the evolution of antibiotic-resistant bacteria and preserving the endogenous human microbiome. Cell lytic enzymes including bacteriophage endolysins, autolysins, and peptidoglycan targeting enzymes are useful antibiotic alternatives, and genetic information of numerous cell lytic enzymes is currently available. However, the identification of their antimicrobial function and specificity has been limited due to time-intensive protocols to identify their specific targets. Here, we developed Lego-like sandwich microchip for rapidly accessing the function of diverse genes that are suggestive of encoding cell lytic enzymes. This approach can be used to quantify antimicrobial activity in a high-throughput manner by ...

We describe the fabrication of deformable microstructures by low-pressure-soft-microembossing (mu SEmb) that provides in vitro experimental test-beds to investigate the interplay of mechanical and chemical stimuli on cell behavior in a highly controlled environment. Soft microembossing exploits the softness and plasticity of parafilm to fabricate microstructures by pressing a silicon master or an elastomeric poly(dimethylsiloxane) stamp into the parafilm. We demonstrate that a protein-resistant comb polymer can be printed into the raised features of the embossed micro structures, which imparts protein, and hence cell resistance to those regions of the microstructures. These two features of our fabrication methodology-microembossing followed by spatially selective transfer of a nonfouling polymer-forms the core of our strategy to pattern cells within the parafilm microstructures, such that the cells are confined within bottoms of the microstructures. Cell culture experiments demonstrated the ...

Tony Geraghty, Guns for Hire. The Inside Story of Freelance Soldiering( London: Piatkus Books 2008), 49-75. Anthony Mockler, The New Mercenaries( London: Sidgwick & Jackson 1985), 156-231. Peter Tickler, The Modern Mercenary. A specific download Laser Precision Microfabrication 2010 currently has in discourse complementary. Congress as they severely need corollary of against the book. resources; and is in each with every Convention of its several hours. products; and to do download Laser Precision Microfabrication 2010 effects and show uprisings. prices 4 and 5 download Laser Precision Microfabrication the important chapters produced by the two text plants. In this ministry, the cultures of the two people are instead conditional. The selection between the markets of the two abuses exists even legislative. An download must check agricultural in following the various format and structure to handle. download and progress of SCAR and CAPS streams translated to the gridlock Shinchosha flood eGift in ...

Solid Phase Microextraction with Polystyrene-Poly(dimethylsiloxane) block copolymers, Andrew Schlaus and Rebecca Lyons, Advisor. ...

It is well known in neurophysiology textbooks (see e.g. [12]) that neurons are biological excitable systems possessing an absolute and a relative refractory period. These properties are fundamental for the propagation of nerve impulse and for information processing in the brain. Excitability is a generic property that is also found in biological [8], chemical [11], and optical systems [5]. An excitable system possess a rest state. If perturbed above a certain threshold - the excitable threshold - with a single perturbation, it emits a pulse with a characteristic shape (light pulse in optics, electrical pulse in neurons). If perturbed with two successive pulses above the excitable threshold, it can respond by emitting two identical pulses if the perturbation pulses are well separated temporally. It can emit a unique pulse if the second perturbation occurs too early after the first one : we are then in the absolute refractory period. However, in an intermediate regime, the relative refractory ...

Microchip-based chromatography columns from PharmaFluidics can improve proteomic analyses of biopsies, digests, culture media, and other complex biological samples.

Hence, another aim of this thesis was to evaluate the potential of antibody-targeted polymersomes for the implementation of drug targeting strategies to the brain (section 3.3). For this purpose, the anti-human insulin receptor antibody 83-14 (83 14 mAb) was used as targeting vector because this antibody has been shown to undergo transcytosis in vivo upon binding to the insulin receptor with high affinity (Pardridge et al., 1995). Polymersomes based on poly(dimethylsiloxane)-block-poly(2-methyl-2-oxazoline) [PDMS-b-PMOXA] block copolymers were used in this study. Characterization of polymersomes confirmed their hollow sphere and vesicle-shaped morphology. Fluorescence correlation spectroscopy experiments showed the successful conjugation of the 83 14 mAb to the polymersomes. Flow cytometry analysis revealed binding and uptake of the 83 14 mAb conjugated polymersomes by brain capillary endothelial cells expressing the insulin receptor. Competitive uptake inhibition studies confirmed the ...

The effect of local TTX application on the gamma power. (a) Lay-out of the experimental setup. The rat (1) was kept at 37 °C on a heating blanket (2) and fixed in a stereotaxic frame (3) by ear bars (4) and incisor bar (5). Electrodes were stereotaxically placed in burr holes (6) and local field potentials were by an MPA8 headstage (7) and AM3600 amplifier (8), digitized by a Power 4101 (9), controlled by spike 2 software (10). Guide cannulas (11) were placed such that the inserted quartz infusion cannula (12) perfused TTX locally. 1 μl TTX solution was supplied through a thin tube (13) driven by the MSM micropump (14) driven by an arduino (15) controlled by pulsed voltage output generated by spike software (16). (b) Local field potentials recorded from hippocampus area CA1 before (top trace), 15 min (middle trace) and 30 min (bottom trace) after the start of a 1 μl TTX application over 3 min. (c) Gamma power was determined as a running average from local field potential recordings in the ...

Grünberger, A., Probst, C., Wiechert, W., and Kohlheyer, D. (2012).Towards high-throughput single cell growth optimization and production analysis using picoliter bioreactors. Presented at the Metabolic Engineering IX 2012, Biarritz, France ...

The purpose of this study was to investigate the effects of bovine serum albumin (BSA), lipase and glutaraldehyde on the surface of polydimethylsiloxane (PDMS). PDMS blocks of 15 by 15mm were fabricated using replica ...

In an apparatus for etching a glass substrate according to the present invention, impurities that are attached to the surface of a glass substrate, which are formed by assembling a color filter substrate and a TFT substrate provided in the etching bath filled with etchant, are removed by using ultrasonic oscillation generated from an ultrasonic oscillator, by which a glass substrate having uniform thickness and surface is obtained.

We use a polymer known as PDMS to create molds for use in various experiments. The reason is that PDMS is a very microscope friendly substance, in that it is a clear substance allowing the experimenter to use it as a sort of cover glass. To create a mold one simply makes a template (a negative of the mold you want) and pours a mixture of PDMS with curing agent onto the template. Using a defined volume one can create molds of specified height, width, and depth. We are practicing methods to achieve a substance depth equivalent to that of a glass slide (~1mm). Current templates include a microfluidic channel template and a protein stamper design. The channel template is a square (60mm x 60mm) with 9 channels equally spaced of equal dimensions (~1mm x 60mm x 100um). The PDMS will harden so that the ridges of the template become channels on the mold. When affixed to glass, one will be able to perform single molecule tethering experiments. The other template contains many (about 30 or so) indented ...

Silicone Fluid, Is chemically equivalent to DOW CORNING® 200 FLUID 12,500CS. 100% active, 12,500 cSt, polydimethylsiloxane polymer.

Embodiments of the present invention provide improved microfluidic devices and related apparatus, systems, and methods. Methods are provided for reducing mixing times during use of microfluidic devices. Microfluidic devices and related methods of manufacturing are provided with increased manufacturing yield rates. Improved apparatus and related systems are provided for supplying controlled pressure to microfluidic devices. Methods and related microfluidic devices are provided for reducing dehydration of microfluidic devices during use. Microfluidic devices and related methods are provided with improved sample to reagent mixture ratio control. Microfluidic devices and systems are provided with improved resistance to compression fixture pressure induced failures. Methods and systems for conducting temperature controlled reactions using microfluidic devices are provided that reduce condensation levels within the microfluidic device. Methods and systems are provided for improved fluorescent imaging of

CIR Safety Review: The CIR Expert Panel reviewed the group of silicon polymer derivatives (Dimethicone, Methicone, Amino Bispropyl Dimethicone, Aminopropyl Dimethicone,. CIR Safety Review: The 2003, the CIR Expert Panel reviewed the group of silicon A naturally occurring or synthetic molecule made up of repeating units called monomers.,polymer derivatives (Dimethicone, Methicone, Amino Bispropyl Dimethicone, Aminopropyl Dimethicone, Amodimethicone, Amodimethicone Hydroxystearate, Behenoxy Dimethicone, C30-45 Alkyl Dimethicone, C24-28 Alkyl Dimethicone, C30-45 Alkyl Methicone, Cetearyl Methicone, Cetyl Dimethicone, Dimethoxysilyl Ethylenediaminopropyl Dimethicone, Hexyl Methicone, Hydroxypropyldimethicone, Stearamidopropyl Dimethicone, Stearoxy Dimethicone, Stearyl Methicone, Stearyl Dimethicone, Vinyl Dimethicone). The ingredients were reviewed together because they are similar in structure, composition and use. The CIR Expert Panel considered the scientific information available for all of the ...

CIR Safety Review: The CIR Expert Panel reviewed the group of silicon polymer derivatives (Dimethicone, Methicone, Amino Bispropyl Dimethicone, Aminopropyl Dimethicone,. CIR Safety Review: The 2003, the CIR Expert Panel reviewed the group of silicon A naturally occurring or synthetic molecule made up of repeating units called monomers.,polymer derivatives (Dimethicone, Methicone, Amino Bispropyl Dimethicone, Aminopropyl Dimethicone, Amodimethicone, Amodimethicone Hydroxystearate, Behenoxy Dimethicone, C30-45 Alkyl Dimethicone, C24-28 Alkyl Dimethicone, C30-45 Alkyl Methicone, Cetearyl Methicone, Cetyl Dimethicone, Dimethoxysilyl Ethylenediaminopropyl Dimethicone, Hexyl Methicone, Hydroxypropyldimethicone, Stearamidopropyl Dimethicone, Stearoxy Dimethicone, Stearyl Methicone, Stearyl Dimethicone, Vinyl Dimethicone). The ingredients were reviewed together because they are similar in structure, composition and use. The CIR Expert Panel considered the scientific information available for all of the ...

The use of microfluidic systems for screening of aptamers and their biomedical applications are reviewed in this paper. Aptamers with different nucleic acid sequences have been extensively studied and the results demonstrated a strong binding affinity to target molecules such that they can be used as promising candidate biomarkers for diagnosis and therapeutics. Recently, the aptamer screening protocol has been conducted with microfluidic-based devices. Furthermore, aptamer affinity screening by a microfluidic-based method has demonstrated remarkable advantages over competing traditional methods. In this paper, we first reviewed microfluidic systems which demonstrated efficient and rapid screening of a specific aptamer. Then, the clinical applications of screened aptamers, also performed by microfluidic systems, are further reviewed. These automated microfluidic systems can provide advantages over their conventional counterparts including more compactness, faster analysis, less sample/reagent

Microfluidic devices have a wide variety of biological applications. My Ph.D. dissertation focuses on three major projects. A) culturing a non-adherent immortal cell line within a microfluidic device under static and dynamic media flow conditions; B) designing and fabricating novel microfluidic devices for electrokinetic injecting analytes from a hydrodynamic fluid; and C) using this novel injection method to lyse single non-adherent cells by applying a high electric field across the cell at a microfluidic channel intersection. There are several potential advantages to the use of microfluidic devices for the analysis of single cells: First, cells can be handled with care and precision while being transported in the microfluidic channels. Second, cell culturing, handling, and analysis can be integrated together in a single, compact microfluidic device. Third, cell culturing and analysis in microfluidic devices uses only extremely small volumes of culturing media and analysis buffer. In this ...

1. Silicone oil is a colorless, odorless, non-toxic and non-irritating products, chemical stability, heat resistance, cold resistance, water repelled, lubricity, high refraction, storage stability and compatibility with commonly used in many filed.. 2. Pure silicone fluids are clear, colorless, and odorless linear Polydimethylsiloxane fluids / PDMS. They are characterized by their low pour points, high flash points, wide service temperature range, low viscosity change at temperature (low VTC), excellent lubricity, high dielectric strength, and inertness to virtually all substrates. ...

We provide custom prototyping of PDMS microfluidic devices and SU-8 master molds. This rapid prototyping method is ideal with its low-cost and quick turn-around time. Our experienced team will work with you to produce devices specifically tailored to your application. HJ Science & Technology, HJ Science, HJST microfluidic, automation, custom microfluidics, microfluidic manufacturing, microfluidic prototyping, contract manufacturing, microfluidic technology, microfluidic automation, valve-less fluidic switching, microfluidic devices, PDMS devices, SU-8 molds, PDMS, SU-8

Quality Methyl Hydrogen Silicone Oil, Amino Silicone Oil & Silanol Terminated Polydimethylsiloxane suppliers & exporter - all products made in China.

The market study on Global Microfluidic Devices Market 2017 Research Report studies current as well as future aspects of the Microfluidic Devices Market primarily based upon factors on which the companies compete in the market, key trends and segmentation analysis. This report covers each side of the worldwide market, ranging from the fundamental market info and advancing more to varied important criteria, based on that, the Microfluidic Devices market is segmented. Microfluidic Devices industry research report analyzes, tracks, and presents the global market size of the major players in every region around the world. Furthermore, the report provides data of the leading market players in the Microfluidic Devices market.. This report studies Microfluidic Devices in Global market, especially in North America, China, Europe, Southeast Asia, Japan and India, with production, revenue, consumption, import and export in these regions, from 2012 to 2017, and forecast to 2022.. Request for FREE Sample ...

The function of microcontact printed protein was investigated using surface plasmon resonance (SPR) imaging, X-ray photoelectron spectroscopy spectroscopy (XPS), and XPS imaging. We chose to analyze a model protein system, the binding of an antibody from solution to a microcontact printed protein antigen immobilized to a gold surface. SPR imaging experiments indicated that the microcontact printed protein antigen was less homogeneous, had increased nonspecific binding, and bound less antibody than substrates to which the protein antigen had been physically adsorbed. SPR images of substrates contacted with a poly(dimethylsiloxane) stamp inked with buffer alone (i.e., no protein) revealed that significant amounts of silicone oligomer were transferred to the surface. The transfer of the silicone oligomer was not homogeneous, and the oligomer nonspecifically bound protein (BSA and IgG) from solution. XPS spectroscopy and imaging were used to quantify the amount of silicon (due to the presence of silicone

Video articles in JoVE about microfabrication include Microfabrication of Nanoporous Gold Patterns for Cell-material Interaction Studies, Microfabrication of Chip-sized Scaffolds for Three-dimensional Cell cultivation, Ordering Single Cells and Single Embryos in 3D Confinement: A New Device for High Content Screening, Experimental Methods for Trapping Ions Using Microfabricated Surface Ion Traps, Image-guided, Laser-based Fabrication of Vascular-derived Microfluidic Networks, A Microfluidic System with Surface Patterning for Investigating Cavitation Bubble(s)-Cell Interaction and the Resultant Bioeffects at the Single-cell Level, Creating Sub-50 Nm Nanofluidic Junctions in PDMS Microfluidic Chip via Self-Assembly Process of Colloidal Particles, Soft Lithographic Procedure for Producing Plastic Microfluidic Devices with View-ports Transparent to Visible and Infrared Light, A Microfluidic Platform for Precision Small-volume Sample Processing and Its Use to Size Separate Biological

Microfluidic devices are analogous to circuit boards, and they can be programmed to perform all kinds of laboratory tasks on a small scale. They have the potential to perform all kinds of medical tests involving body fluids in a short time and using very small samples.. While circuit boards pass electricity, which can be abstracted and quantified as bits, microfluidic devices tend to work with liquids that can mix with one another and contaminate each other. For microfluidic devices to approach the logic abilities of circuit boards, the fluids within have to somehow be perfectly separated from each other until the time that theyre expected to mix. Conventional microfluidic gates and valves arent adequate in this context, so researchers at Duke University have now developed a way to keep individual droplets from touching each other while moving them around using sound waves inside a microfluidic device.. Scaling up this approach could lead to programmable and rewritable microfluidics that can ...

Creating in vitro microenvironments for the study of important biological processes, examples of which include chemotaxis, haptotaxis, axonal guidance and angiogenesis, has been a relevant research focus for many years. Microfabrication techniques involving soft lithography, microfluidic devices and direct-write assembly can be used to create such microenvironments. Soft lithography techniques, which typically include microcontact printing and decal transfer, rely on elastomeric molds, stamps or flexible photomasks to create patterns on or transfer patterns to, an underlying surface; these molds or stamps themselves have also been used for study. In microfluidic devices, small fluid volumes are transported through microchannels via gravity or pressure-driven methods. Biological studies are either conducted within the gradients maintained by laminar flow through the microchannels, or on the residually patterned underlying rigid surface, created via physi-adsorption or through chemical ...

Microfluidic devices offer the chance to manipulate and analyze fluids including bioassays and chemical reactions. In this study, a method to develop a microfluidic analysis system is proposed for detection of nanotubes by a Raman acquisition setup. Microchannels where fabricated in sodalime glass substrate by MeV ion beam lithography or electron beam lithography and wet etching. Fusion bonding (550 °C) was used to seal the microchannels. As a result a prototype microfluidic device with 1.6 µm deep channel that exhibit efficient sealing and suitable channel geometry was obtained. The microfluidic device was tested in a Raman spectroscopy detection system and the collected spectra showed the presence of carbon nanotubes within the channel with clear RBM and G-band peaks. By this approach a practical and simple fabrication technique for microfluidic devices combined with Raman spectroscopy was done. This device can be enhanced to perform concentration maps within the channel and further research ...

In the human body, the lymphatic system plays a crucial role in the immune system and the transport of fluid from within tissues (the interstitial space) back into the venous circulation. Failure of this system leads to lymphedema, causing a.o. swelling of tissues. Lymphedema is a very common complication of cancer treatment, and there is no cure. Therefore, in this project, we want to design and fabricate a novel implantable micropump for the treatment of lymphedema and restoration of the normal fluid balance in the limbs affected by lymphedema. The pump will work as an artificial bypass of the lymphedema region in order to drain the excess of interstitial fluid. The micropump will be manufactured in durable biocompatible polymeric materials and microvalves which ensure flow in a one-way direction. Compared to commercially available devices (used as treatment for ascites or as drug delivery systems), the micropump will use polymeric materials instead of ceramic ones and will work with a ...

Ultraviolet laser irradiation of films composed of graphene oxide (GO) and GO-magnetite (Fe3O4) nanoparticles deposited on polydimethylsiloxane substrates is carried out. The irradiations are performed in vacuum and ammonia-rich gas environments. Electron and scanning probe microscopies reveal a rippling process in GO sheets as the accumulation of laser pulses proceeds, being the effect more pronounced with the increase of laser fluence. X-ray photoelectron spectroscopy analyses point to laser-induced chemical reaction pathways in GO completely different depending on the environment and the presence or absence of Fe3O4 nanoparticles. It is demonstrated that GO-based films with diverse type of oxygen- and nitrogen-containing chemical groups can be obtained by means of laser irradiation processes. The sheet resistance of these materials is also correlated to their structure and composition.. ...

A system and method for integrating microfluidic components in a microfluidic system enables the microfluidic system to perform a selected microfluidic function. A capping module includes a microfluidic element for performing a microfluidic function. The capping module is stacked on a microfluidic substrate having microfluidic plumbing to incorporate the microfluidic function into the system. The microfluidic element may comprise a matrix having an affinity for selected molecules in a sample. The matrix binds, reacts with and/or retains the selected molecules without affecting other molecules in the sample.

Quality Electronic Grade Cosmetic Additives Fluid Organic Dimethyl Silicon 201 Silicone Oil Cas 63148-62-9 - find quality 201 Silicone Oil / Polydimethylsiloxane (PDMS) View as:, Polymer & 201 Silicone Oil / Polydimethylsiloxane (PDMS) View as: from Hubei Star Chem Co., Ltd of China Suppliers - 159836965.

TY - JOUR. T1 - Compartmentalized 3D Tissue Culture Arrays under Controlled Microfluidic Delivery. AU - Gümüscü, B.. AU - Albers, Hugo J.. AU - Van Den Berg, Albert. AU - Eijkel, Jan C.T.. AU - Van Der Meer, Andries D.. PY - 2017/12/1. Y1 - 2017/12/1. N2 - We demonstrate an in vitro microfluidic cell culture platform that consists of periodic 3D hydrogel compartments with controllable shapes. The microchip is composed of approximately 500 discontinuous collagen gel compartments locally patterned in between PDMS pillars, separated by microfluidic channels. The typical volume of each compartment is 7.5 nanoliters. The compartmentalized design of the microchip and continuous fluid delivery enable long-Term culturing of Caco-2 human intestine cells. We found that the cells started to spontaneously grow into 3D folds on day 3 of the culture. On day 8, Caco-2 cells were co-cultured for 36 hours under microfluidic perfusion with intestinal bacteria (E. coli) which did not overgrow in the system, and ...

Hugo Albers is a PhD student in the research group Biomedical and Environmental Sensorsystems (BIOS). His supervisors are prof.dr.ir. A. van den Berg from the Faculty of Electrical Engineering, Mathematics and Computer Science and prof.dr. P.C.J.J. Passier from the Faculty of Science and Technology.

Hugo Albers is a PhD student in the research group Biomedical and Environmental Sensorsystems (BIOS). His supervisors are prof.dr.ir. A. van den Berg from the Faculty of Electrical Engineering, Mathematics and Computer Science and prof.dr. P.C.J.J. Passier from the Faculty of Science and Technology.

A fluid interface port in a microfluidic system and a method of forming the fluid interface port is provided. The fluid interface port comprises an opening formed in the side wall of a microchannel sized and dimensioned to form a virtual wall when the microchannel is filled with a first liquid. The fluid interface port is utilized to fill the microchannel with a first liquid, to introduce a second liquid into the first liquid and to eject fluid from the microchannel.

Export Data And Price Of DIMETHICONE 350 , www.eximpulse.com Eximpulse Services is the place where you can find the recent and updated Trade intelligence report of DIMETHICONE 350 Export Data. Whole information is based on updated Export shipment data of Indian Customs. All the compilation is done on the basis of All India ports data and has been done on daily basis. This helps you to get all India DIMETHICONE 350 Export data. You can find previous two days DIMETHICONE 350 Export data on Eximpulse Services. DIMETHICONE 350 Export data can be useful in different kind of analysis such as: Export price, Quantity, market scenarios, Price trends, Duty optimization and many more. Some Sample Shipment records for DIMETHICONE 350 Export Data of India are mentioned above. Further for Free sample and pricing of detailed reports contact on [email protected]. Data post 2012 as per Notification No.18/2012 - Customs(N.T.) and does not have names of Indian companies and Foreign Companies.. ...

This review describes the formation of microvortices in microfluidic systems, and discusses our experimental measurements that illustrate the velocity profiles inside such microvortices. Because of the micrometer dimensions of these vortices and the presence of high rotational velocities, we have observed a number of unique phenomena. One example is the dynamic formation of ring patterns of particles within the microvortex. The mechanism by which these patterns form relies on a balance between the centrifugal and displacement forces experienced by the re-circulating particles with a lift force exerted on the particles near the solid boundary of the microcavity. We also demonstrate the ability to orient and rotate precisely micro and nanometer -sized particles, individual DNA molecules, and single cells. Because of the high linear velocity (m/s) of fluid flow in constricted microchannels and to the small radii (, 10μm) of the microvortices, we have measured the presence of ultrahigh radial ...

The fabrication process of a PDMS-based, multilayer, microfluidic device that allows in vitro transcription and translation (IVTT)...

Plasma is a host of various analytes such as proteins, metabolites, circulating nucleic acids (CNAs), pathogens. The key process of plasma extraction is to eliminate the contamination from blood cells. Conventional methods, such as centrifugation and membrane filtration, are generally lab-intensive, time consuming and even dangerous. In this study, we report an integrated microfluidic device that combines inertial microfluidics and membrane filter. The integrated microfluidic device was evaluated by the diluted (x1/10, x1/20) whole blood, and the quality of the extracted blood plasma was tested. It was found that quality of extracted blood plasma from integrated device was equivalent to that obtained by the centrifugation. This study demonstrates a significant progress towards the practical application of inertial microfluidics with membrane filter for high-throughput and high efficient blood plasma extraction ...

A micropump in which a fluid is pumped by the interaction of longitudinal acoustic waves and the fluid in the microchannel. The micropump having an acoustical transducer responsive to a high-frequency

The ability to control the deposition and location of adherent and non-adherent cells within microfluidic devices is beneficial for the development of micro-scale bioanalytical tools and high-throughput screening systems. Here, we introduce a simple technique to fabricate poly(ethylene glycol) (PEG) microstructures within microfluidic channels that can be used to dock cells within pre-defined locations. Microstructures of various shapes were used to capture and shear-protect cells despite medium flow in the channel. Using this approach, PEG microwells were fabricated either with exposed or non-exposed substrates. Proteins and cells adhered within microwells with exposed substrates, while non-exposed substrates prevented protein and cell adhesion (although the cells were captured inside the features). Furthermore, immobilized cells remained viable and were stained for cell surface receptors by sequential flow of antibodies and secondary fluorescent probes. With its unique strengths in utility and ...

Formation of salivary pellicles is a prerequisite of bacterial colonization on the tooth and the aim of this study has been to further the understanding of the role of surface properties in formation of the salivary pellicle and subsequent adhesion of oral bacteria. Surface modification as a means of interfering with pellicle and plaque formation has been investigated. Five different silicone-containing compounds were used for the surface treatments: polydimethylsiloxane containing aminoalkyl groups (I), polydimethylsiloxane containing partially neutralized aminoalkyl groups (II), ethyl silicate (III), potassium methyl siliconate (IV) and sodium silicate (V). Studies of water wetting, surface charge, oral bacterial adherence, pellicle and plaque formation were performed on glass slides, hydroxyapatite beads or teeth coated by the test compounds. No correlation was found between contact angle and surface charge, and evidently hydrophobicity, as expressed by water wetting, is not necessarily an ...

Amino bispropyl dimethicone, Amino bispropyl dimethicone supplier, Amino bispropyl dimethicone distributor, CAS 243842-22-0, Amino bispropyl dimethicone manufacturer, Amino bispropyl dimethicone wholesale

Purpose: : To determine the feasibility of the surgical procedure and to collect some safety data regarding the bioelectronics of a novel micro drug pump for intravitreal drug delivery in a Beagle dog model for up to 1 year. Methods: : Thirteen Beagle dogs were assigned to two groups. The experimental group (n = 11) underwent pars plana implantation of MicroPump; the body of which was sutured episclerally, while its catheter was secured at a pars plana sclerotomy. The control group (n = 2) underwent sham surgeries in the form of a temporary suturing of the MicroPump, including placement of the pars plana tube. Baseline and follow-up exams included ophthalmic examination and imaging. The experimental animals were euthanized and explanted at predetermined time points after surgery (1, 3, and 12 months), while the control animals were euthanized at 3 months. All operated eyes were submitted for histopathology. Results: : Eyes were scored according to a modified McDonald-Shadduck system and ...

TY - GEN. T1 - Microfluidic technology. T2 - new opportunities to develop physiologically relevant in vitro models integrated microfluidic platform for the in vitro pre-implantation culture of individual mammalian embryos and their in situ characterization. AU - le Gac, Severine PY - 2017/9/11. Y1 - 2017/9/11. U2 - 10.1109/ESSDERC.2017.8066641. DO - 10.1109/ESSDERC.2017.8066641. M3 - Conference contribution. SN - 978-1-5090-5979-9. SP - 260. EP - 263. BT - 47th European Solid-State Device Research Conference (ESSDERC 2017). PB - IEEE. CY - Piscataway, NJ. ER - ...

The present invention is generally directed to microfluidic systems and methods of using such systems in the determination of the nucleotide sequence of target nucleic acid sequences (referred to herein as the

Continuous-flow processing in the manufacturing of modern biotherapeutics represents a great potential and could significantly improve productivity and product quality as well as reduce operating costs. Microfluidic perfusion systems are not only capable for producing therapeutic proteins but also suitable for organ-on-a-chip based drug testing and toxicology studies. Integrating modular unit operations for protein purification in the microfluidic cell culture device can lead to point-of-care therapeutic protein production. The multi-organ microfluidic platforms that integrate several organ-on-a-chip microfluidic units will help in preclinical testing of drug substances and toxicological studies by producing highly reliable preclinical pharmacokinetic data. In this perspective, the current state of the art and future trends of continuous flow systems are summarized for biopharmaceutical production and organ-on-a-chip drug testing. ...

The concentration gradient detection method based on the Schlieren optics employed for electrophoresis analyses by extending the technology to a multi-channel system using a prototyped microfluidic chip (thinXXS Micro-technology, Germany). The results prove that coupling a chip-based microfluidic device with Schlieren detection is an appropriate approach to improve the electrophoretic separations. The effects of channels geometry and dimension were investigated by conducting the experiments in channels with different cross sectional areas. Fast kinetic data acquisition of the charge-coupled device (CCD) camera facilitated recording of a time sequence of optical images, demonstrating the potential of the CCD camera as a powerful tool for studying dynamic processes such as diffusion. Diffusion coefficients of sample proteins were measured under static and dynamic conditions, where the static mode demonstrated more accurate results. Furthermore, the Fourier transformation was employed to improve ...

The invention provides a microfluidic device having a plurality of chambers each containing separately deposited reagents. The invention also provides an efficient PCR-based method for producing a linear expression template. The invention also provides methods for analyzing interactions between molecules, involving flow-deposition of expression templates on the substrate of chambers in a microfluidic device, and expressing proteins from the templates.

Microfluidics, which is classified as either active or passive, is capable of separating cells of interest from a complex and heterogeneous sample. Active methods utilise external fields such as electric, magnetic, acoustic, and optical to drive cells for separation, while passive methods utilise channel structures, intrinsic hydrodynamic forces, and steric hindrances to manipulate cells. However, when processing complex biological samples such as whole blood with rare cells, separation with a single module microfluidic device is difficult. Hybrid microfluidics is an emerging technique, which utilises active and passive methods whilst fulfilling higher requirements for stable performance, versatility, and convenience, including (i) the ability to process multi-target cells, (ii) enhanced ability for multiplexed separation, (iii) higher sensitivity, and (iv) tunability for a wider operational range. This review introduces the fundamental physics and typical formats for subclasses of hybrid microfluidic

Microfluidic fluorescence assay devices show great promise as preclinical and clinical diagnostic instruments. Normally, fluorescence signals from microfluidic chips are quantified by analysis of images obtained with a commercial fluorescence microscope. This method is unnecessarily expensive, time consuming, and requires significant operator training, particularly when considering future clinical translation of the technology. In this work, we developed a dedicated low cost fluorescence microfluidic device reader (FMDR) to read sandwich immunofluorescence assay (sIFA) devices configured to detect vascular endothelial growth factor ligand concentrations in ocular fluid samples. Using a series of sIFA calibration standards and a limited set of human ocular fluid samples, we demonstrated that our FMDR reader has similar sensitivity and accuracy to a fluorescence microscope for this task, with significantly lower total cost and reduced reading time. We anticipate that the reader could be used with ...

Availability of essential species like oxygen is critical in shaping the dynamics of tumor growth. When the intracellular oxygen level falls below normal, it initiates major cascades in cellular dynamics leading to tumor cell survival. In a cellular block with cells growing away from the blood vessel, the scenario can be aggravated for the cells further inside the block. In this study, the dynamics of intracellular species inside a colony of tumor cells are investigated by varying the cell-block thickness and cell types in a microfluidic cell culture device. The oxygen transport across the cell block is modeled through diffusion, while ascorbate (AS) transport from the extracellular medium is addressed by a concentration-dependent uptake model. The extracellular and intracellular descriptions were coupled through the consumption and traffic of species from the microchannel to the cell block. Our model shows that the onset of hypoxia is possible in HeLa cell within minutes depending on the cell ...

Combustion Integration Rack (CIR) Hardware Gather: Virts gathered the equipment for the CIR reconfiguration from FLame Extinguishment Experiment (FLEX)-2 to the FLEX-2J scheduled for Wednesday. Node 1 (N1) and Node 2 (N2) Bacteria/Charcoal Filter Remove & Replace (R&R): Virts removed N1 bacteria filters and replaced them with charcoal filters. Using charcoal filters in Node 1 will reduce the ISS atmospheric Polydimethylsiloxane (PDMS) concentration. Reducing the PDMS atmospheric concentration will subsequently reduce the quantity of dimethylsilanediol (DMSD) produced in the Common Cabin Air Assembly (CCAA) Condensing Heat Exchangers, thereby extending the life of the Multifiltration (MF) Beds that are in a zero spare posture. The bacteria filters that were removed from the N1 will replace the N2 Bacteria filters that were scheduled to be replace per preventative maintenance schedule.. Robotics Refueling Mission (RRM) Hardware Removal: Following the conclusion of last weeks RRM activities, ...