Search Results
Results 201 - 250 of 1668
< 1 2 3 4 5 6 7 8 9 10 >
Toivola Minna - - 2010
Stainless steel based dye solar cells have been upscaled from small, laboratory size test cells of 0.32 cm2 active area to 6 cm x 6 cm "mini-modules" with active areas ca. 15 cm2. Stainless steel works as the photoelectrode substrate whilst the counter electrode is prepared on indium-doped tin oxide ...
Loomis Kristin - - 2010
The CD22 antigen is a viable target for therapeutic intervention for B-cell lymphomas. Several therapeutic anti-CD22 antibodies as well as an anti-CD22-based immunotoxin (HA22) are currently under investigation in clinical settings. Coupling of anti-CD22 reagents with a nano-drug delivery vehicle is projected to significantly improve treatment efficacies. Therefore, we generated ...
Thein Myo - - 2010
The underlying sensing mechanism of single-cell-based integrated microelectrode array (IMA) biosensors was investigated via experimental and modeling studies. IMA chips were microfabricated and single-cell-level manipulation was achieved through surface chemistry modification of IMA chips. Individual fibroblast cells (NIH3T3) were immobilized on either lysine-arginine-glycine-aspartic acid (KRGD) short peptide-modified or fibronectin extracellular-cell-adhesion-molecule-modified ...
Shafiee Hadi - - 2010
Contactless dielectrophoresis (cDEP) is a recently developed method of cell manipulation in which the electrodes are physically isolated from the sample. Here we present two microfluidic devices capable of selectively isolating live human leukemia cells from dead cells utilizing their electrical signatures. The effect of different voltages and frequencies on ...
Kobel Stefan - - 2010
The poor efficiency of microfluidic single cell trapping is currently restricting the full potential of state-of-the-art single cell analyses. Using fluid dynamics simulations in combination with particle image velocimetry to systematically optimize trap architectures, we present a microfluidic chip with enhanced single cell trapping and on-chip culture performance. Upon optimization ...
Burks Scott R - - 2010
Electron paramagnetic resonance (EPR) imaging is an emerging modality that can detect and localize paramagnetic molecular probes (so-called spin probes) in vivo. We previously demonstrated that nitroxide spin probes can be encapsulated in liposomes at concentrations exceeding 100 mM, at which nitroxides exhibit a concentration-dependent quenching of their EPR signal ...
Ciesielski Peter N - - 2010
Photosynthesis is the process by which Nature coordinates a tandem of protein complexes of impressive complexity that function to harness staggering amounts of solar energy on a global scale. Advances in biochemistry and nanotechnology have provided tools to isolate and manipulate the individual components of this process, thus opening a ...
Gagnon Zachary - - 2010
We integrate electrothermally induced micro-pumps and dielectrophoretic (DEP) traps into micro-circulating fluidic channel loops for yeast cell concentration and separation, two important on-chip cell manipulation tasks, with the same embedded electrodes on-chip. Each fluidic loop design contains well-defined high and low field regions that serve for both fluid transport and ...
Fondell Amelie - - 2010
PURPOSE: For the treatment of cancer, the therapeutic potential of short-range, low-energy Auger-electron emitters, such as (125)I, is getting progressively wider recognition. The potency of Auger-electron emitters is strongly dependent on their location in close vicinity to DNA. We have developed a new two-step targeting strategy to transport (125)I into ...
Kamps Jan A - - 2010
Liposome-cell interactions have been assessed for over 30 years now by an enormous variety of approaches and methods. In-depth knowledge of liposome-cell interaction is still very relevant since new concepts and applications applying liposomes are being developed every day. This chapter does not aim to give a complete overview on ...
Church Christopher - - 2010
Lysing cells is an important step in the analysis of intracellular contents. Concentrating cells is often required in order to acquire adequate cells for lysis. This work presents an integrated concentration and lysis of mammalian cells in a constriction microchannel using dc-biased ac electric fields. By adjusting the dc component, ...
Zhu Ke - - 2010
The dielectrophoretic behavior of active, dead, and dormant Mycobacterium smegmatis bacterial cells was studied. It was found that the 72-h-old dormant cells had a much higher effective particle conductivity (812+/-10 muS cm(-1)), almost double that of active cells (560+/-20 muS cm(-1)), while that of dead (autoclaved) M. smegmatis cells was ...
Sekijima Masaru - - 2010
We investigated the mechanisms by which radiofrequency (RF) fields exert their activity, and the changes in both cell proliferation and the gene expression profile in the human cell lines, A172 (glioblastoma), H4 (neuroglioma), and IMR-90 (fibroblasts from normal fetal lung) following exposure to 2.1425 GHz continuous wave (CW) and Wideband ...
Braeken Dries - - 2010
In drug screening and pharmaceutical research, high-throughput systems that are able to perform single-cell measurements are highly desired. Micro-electrode arrays try to answer this need but still suffer from significant drawbacks such as a small amount of electrodes and the inability to address single cells. Here, we present a novel ...
Hoettges Kai F - - 2010
Dielectrophoresis (DEP) is a technique which offers label-free measurement of cell electrophysiology by monitoring its movement in non-uniform electric fields. In this chapter, the theory underlying DEP is explored, as are the implications of the development of equipment for taking such measurements. Practical considerations such as the selection of a ...
Jun Bong-Hyun - - 2010
In this study, surface-enhanced Raman spectroscopy (SERS)-encoded magnetic nanoparticles (NPs) are prepared and utilized as a multifunctional tagging material for cancer-cell targeting and separation. First, silver-embedded magnetic NPs are prepared, composed of an 18-nm magnetic core and a 16-nm-thick silica shell with silver NPs formed on the surface. After simple ...
Mendon?a Liliana S - - 2010
The present work aimed at the development and application of transferrin receptor (TrfR)-targeted sterically stabilized liposomes encapsulating anti-BCR-ABL siRNA or asODN. Transferrin was coupled to the surface of liposomes encapsulating siRNA or asODN through the postinsertion method. Cell association and internalization were assessed by flow cytometry and confocal microscopy, respectively. ...
Fatoyinbo Henry O - - 2010
In this paper, the use of non-uniform ac electric fields on biological cells for bioanalysis, through multiple, independently configurable channels is presented. The programmable system has been used to obtain the dielectrophoretic spectra of cells in near real time, within 90 seconds. This is a significant improvement on existing dielectrophoretic ...
Fei Zhengzheng - - 2010
Electroporation is one of the most popular nonviral gene transfer methods for embryonic stem cell transfection. Bulk electroporation techniques, however, require a high electrical field and provide a nonuniform electrical field distribution among randomly distributed cells, leading to limited transfection efficiency and cell viability, especially for a low number of ...
Santos Edorta - - 2010
The field of cell encapsulation is advancing rapidly. This cell-based technology permits the local and long-term delivery ofa desired therapeutic product reducing or even avoiding the need ofimmunosuppressant drugs. The choice of a suitable material preserving the viability and functionality of enclosed cells becomes fundamental if a therapeutic aim is ...
Minnikanti S - - 2010
While there have been many attempts at patterning cells onto substrates, a reliable method for trapping cell clusters and forming cell arrays in a predefined geometry remains to be demonstrated. We intend to develop a multielectrode array platform to initially trap cells via dielectrophoresis (DEP) and to later measure their ...
Mykhaylyk Olga - - 2010
In a magnetofection procedure, self-assembling complexes of enhancers like cationic lipids with plasmid DNA or small interfering RNA (siRNA) are associated with magnetic nanoparticles and are then concentrated at the surface of cultured cells by applying a permanent inhomogeneous magnetic field. This process results in a considerable improvement in transfection ...
Wiegering V - - 2010
Juvenile Idiopathic Arthritis (JIA) is the most common cause of chronic arthritis in childhood and adolescents and encompasses a heterogeneous group of different diseases. Due to the promising results of B-cell depleting therapies in rheumatoid arthritis the role of B-cells in autoimmune diseases has to be discussed in a new ...
Sawan M - - 2010
We describe in this paper cells sensing and manipulation methods, as well as platforms based on Lab-on-chip devices. Among other contributions, new circuit and microfluidic techniques, and packaging methods are proposed for efficient cells manipulation and detection. The proposed devices include high-sensitivity sensing circuits (200 mV/fF), low-pressure liquid injection interfaces ...
Thomas Rupert S W - - 2010
We describe a system for the isolation, concentration, separation, and recovery of human osteoblast-like cells from a heterogeneous population using dielectrophoretic ring traps. Cells flowing in a microfluidic channel are immobilized inside an electric field cage using negative dielectrophoresis. A planar ring electrode creates a closed trap while repelling surrounding ...
Orive Gorka - - 2010
The exciting developments in the field of drug delivery have already had an enormous impact on medical technology, facilitating the administration of many drugs and improving the pharmacokinetics of many others. The past few years have also seen several firsts, including the design of novel tissue engineered approaches, intriguing advances ...
Saczko Jolanta - - 2010
The effectiveness of the photodynamic therapy (PDT), a low-invasive and targeted therapy of cancer, could be intensified by increasing the intracellular transport of a photosensitizer. The electroporation is used to generate non-specific transient nanopores that facilitate local drug delivery into cells. Photodynamic therapy assisted by electroporation was tested in vitro ...
Lee Seung Won - - 2010
A single-compartmented microbial fuel cell composed of a graphite felt anode modified with Neutral Red (NR-anode) and a porous Fe(II)-carbon cathode (FeC-cathode) were compared for electricity generation from Microbacterium sp. and Pseudomonas sp. under identical conditions. Pseudomonas sp. was more than four times the size of Microbacterium sp. based on ...
Santos Adriana O - - 2010
Anticancer systemic gene silencing therapy has been so far limited by the inexistence of adequate carrier systems that ultimately provide an efficient intracellular delivery into target tumor cells. In this respect, one promising strategy involves the covalent attachment of internalizing-targeting ligands at the extremity of PEG chains grafted onto liposomes. ...
Pan Yuliang - - 2010
A novel method for selective collection and detection of human acute leukemia cells has been proposed using aptamer-conjugated magnetic beads (apt-MBs) and a magnet-quartz crystal microbalance (QCM) system. The sgc8c aptamer-conjugated MBs specifically binding to CCRF-CEM cells were used for target cell extraction from complex matrixes, and the magnet-QCM system ...
Dekker Arjan - - 2009
Scaling up microbial fuel cells (MFCs) is inevitable when power outputs have to be obtained that can power electrical devices other than small sensors. This research has used a bipolar plate MFC stack of four cells with a total working volume of 20 L and a total membrane surface area ...
Ul Haque Aeraj - - 2009
Advancements in microfabrication technology have lead to the development of planar micro-pore electroporation technology. This technology has been shown to provide greater control in single cell manipulation, and electroporation which is independent from cell size. In this work we report direct and spatially resolved characterization of electric currents within a ...
McCaig Colin D - - 2009
Cells undergo a variety of physiological processes, including division, migration and differentiation, under the influence of endogenous electrical cues, which are generated physiologically and pathologically in the extracellular and sometimes intracellular spaces. These signals are transduced to regulate cell behaviours profoundly, both in vitro and in vivo. Bioelectricity influences cellular ...
Mykhaylyk Olga - - 2009
The magnetic labeling of living cells has become of major interest in the areas of cell therapy and tissue engineering. Magnetically labeled cells have been reported to allow increased and controlled seeding, tracking, and targeting of cells. In this work, we comprehensively characterize magnetic nanoparticles (MNPs) possessing a magnetite core ...
Chen Chin-Yu - - 2009
For this study, twisted nematic liquid crystals (TN-LCs) are sandwiched between two cross-embedded wire-grid polarizers (WGPs) as alignment and electrodes for projection displays. In the proposed device, the WGPs replace not only the sheet polarizers in a conventional TN-LC cell, but also the front and rear alignment layers and transparent ...
Pérez-Castejón C - - 2009
Common concern about the biological effects of electromagnetic fields (EMF) is increasing with the expansion of X-band microwaves (MW). The purpose of our work was to determine whether exposure to MW pulses in this range can induce toxic effects on human astrocytoma cells. Cultured astrocytoma cells (Clonetics line 1321N1) were ...
Kim Dong-Hyun - - 2010
Nanomagnetic materials offer exciting avenues for probing cell mechanics and activating mechanosensitive ion channels, as well as for advancing cancer therapies. Most experimental works so far have used superparamagnetic materials. This report describes a first approach based on interfacing cells with lithographically defined microdiscs that possess a spin-vortex ground state. ...
Upadhyaya Sarvesh - - 2010
Cell based screening assays are increasingly used in drug discovery due to the physiological significance of the results and high content information obtained from them. Miniaturization of this format, currently carried out in microwell plates, is at its limit due to increased unnatural interaction of cells with walls inside micro-wells. ...
Robert Damien - - 2010
The in vitro generation of engineered tissue constructs involves the seeding of cells into porous scaffolds. Ongoing challenges are to design scaffolds to meet biochemical and mechanical requirements and to optimize cell seeding in the constructs. In this context, we have developed a simple method based on a magnetic tweezer ...
Varma Sarvesh - - 2010
This paper presents a novel method for cell positioning on a substrate which combines the optical quality of glass and the cell-repelling property of fluoropolymers. The process employs plasma lithography, which utilizes the high-resolution patterning of photolithography along with the versatility of the plasma polymerization. When mammalian cells were grown ...
Fujiwara Takahiro - - 2010
Octaarginine (R8)-modified liposomes have been used to deliver therapeutic substances into cells owing to the efficient cellular uptake via macropinocytosis. Recent analyses revealed that R8-modified liposomes are mainly taken up via macropinocytosis, and escape from endosomes efficiently to avoid lysosomal degradation in non-polarized NIH-3T3 cells. In the present study, we ...
Coman Vasile - - 2009
The present study explores genetic engineering of the respiratory chain and the application of two different flexible osmium redox polymers to achieve efficient electric communication between the gram-positive organism Bacillus subtilis and an electrode. Poly(1-vinylimidazole)(12)-[Os-(4,4'-dimethyl-2,2'-bipyridyl)(2)Cl(2)](+/2+) (osmium redox polymer I) and poly(vinylpyridine)-[Os-(N,N'-methylated-2,2'-biimidazole)(3)](2+/3+) (osmium redox polymer II) were investigated for efficient electrical ...
Raffa Vittoria - - 2010
The use of controlled electric fields to facilitate cell permeabilisation for enhanced cellular uptake of molecules is well established. The main limitation to the application of this technology in clinical practice is the requirements of high voltages which cause significant cell death in the target tissue. This paper presents a ...
Meng Fanben - - 2009
A strategy to assemble cells on a solid support surface, here the surface of a gold electrode, is developed by transfecting cells with thiolated DNA molecules which have been immobilized on the gold electrode surface in advance. This strategy to assemble cells can present a general and convenient method for ...
Valley J K - - 2009
Optoelectronic tweezers (OET) is a promising approach for the parallel manipulation of single cells for a variety of biological applications. By combining the manipulation capabilities of OET with other relevant biological techniques (such as cell lysis and electroporation), one can realize a true parallel, single-cell diagnostic and stimulation tool. Here, ...
Sarvestani Amir Sabet - - 2010
In order to evaluate the influence of static magnetic fields (SMF) on the progression of cell cycle as a monitor of presumptive genotoxicity of these fields, the effects of a 15 mT SMF on cell cycle progression in rat bone marrow stem cells (BMSC) were examined. The cells were divided ...
Wang Ji-Wei - - 2010
Measurements on single cells provide more accurate and in-depth information about electrical properties than those on pathological tissues. The relationship between electrode geometry and the location of a cell on microfluidic devices greatly affects the accuracy of single-cell impedance measurement. Accordingly, this study presents numerical solutions from the FEM simulation ...
Hambourger Michael - - 2009
A photoelectrochemical biofuel cell has been developed which incorporates aspects of both an enzymatic biofuel cell and a dye-sensitized solar cell. Photon absorption at a porphyrin-sensitized n-type semiconductor electrode gives rise to a charge-separated state. Electrons and holes are shuttled to appropriate cathodic and anodic catalysts, respectively, allowing the production ...
Kirschbaum Michael - - 2009
In order to elucidate the dynamics of cellular processes that are induced in context with intercellular communication, defined events along the signal transduction cascade and subsequent activation steps have to be analyzed on the level of individual cells and correlated with each other. Here we present an approach that allows ...
Ferrier Graham A - - 2009
In biomedical applications ranging from the study of pathogen invasion to drug efficacy assays, there is a growing need to develop minimally invasive techniques for single-cell analysis. This has inspired researchers to develop optical, electrical, microelectromechanical and microfluidic devices for exploring phenomena at the single-cell level. In this work, we ...
< 1 2 3 4 5 6 7 8 9 10 >