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Bare Silicon Indexed Sindex™ Chip

The Sindex™ chip is a 4×4 mm silicon substrate containing topographically defined pads that are arrayed within an alphanumeric indexing system. The pads are flat and smooth, making them ideal for fluorescence microscopy and atomic force microscopy. The indexing system allows precise relocation of specific positions on the chip.

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Probing Cellular Responses to Extracellular Signals through Direct Writing of Proteins

American Society for Cell Biology, 2005

J. Werbin,1 C. Lemmon,2 G. Ledung,3 W. F. Heinz,1 L. H. Romer,4 J. H. Hoh1
1 Physiology, Johns Hopkins University School of Medicine, Baltimore, MD
2 Biomedical Engineering, Johns Hopkins University School of Medicine, Baltimore, MD
3 Mlardalen University, Eskilstuna, Sweden
4 Anesthesiology & Crit Care Med, Johns Hopkins University School of Medicine, Baltimore, MD

Interactions between cells and the extracellular environment play a central role in a number of biological phenomena such as tissue growth, cell differentiation and migration. Patterning biomolecules at high resolution on solid supports is a powerful means to investigate how cells interpret and respond to spatially defined extracellular cues. We used a new technology based on microfabricated surface patterning tools, which delivers a protein solution (10-15 -10 -18 liters) to the surface via a microchannel in small cantilever (NanoArrayer, Bioforce Nanosciences). This direct writing process transfers proteins to the substrate by capillary action when the tool touches the surface for times ~100 ms. Proteins can be bound to the surface by adsorption, or via covalent chemistry. The resulting feature sizes range from submicrometer to tens of micrometers, and pattern dimensions are typically 0.5 x 0.5 mm. A series of patterning parameters and conditions have been optimized, and we have constructed glass substrates with a number of different proteins and peptides in complex patterns with multiple components. For example, patterns that are composed of fibronectin and vitronectin where the distance between the two molecules is subcellular, such that a single cell can contact both fibronectin and vitronectin at several well-defined points, have been produced. These patterns have been characterized by immunofluorescence, and are stable under cell culture conditions. In experiments with Mouse Embryo Fibroblasts plated on micropatterned fibronectin in serum-free medium, immunofluorescence labeling revealed that vinculin was localized to the patterned fibronectin foci in semilunar adhesions with concavities toward the cell center. These findings demonstrate spatial control over focal adhesion formation, and provide a foundation to investigate mechanisms by which different molecules contribute to the contacts these cells make with the extracellular environment.

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Directed Self-Assembly of Polystyrene Spheres for Biophotonics and Surface Plasmon Based Sensors

LEOS 2007: The 20th Annual Meeting of the IEEE Lasers and Electro-Optics Society. Lake Buena Vista, FL, USA

Publication Date: 21-25 Oct. 2007; Page(s): 298-299

John E. McGlade, John F. Muth

North Carolina State University, Electrical and Computer Engineering

Abstract: The self assembly of sub-micron scale spheres is useful to produce arrays of nanostructures by shadow masking materials depositions. A method to produce arrays of 5 to 20 μm length scale patterns of nanostructures is presented.

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Towards a Method for Printing a Network of Chick Forebrain Neurons for Biosensor Applications

Proceedings of the 29th Annual International Conference of the IEEE EMBS Cité Internationale, Lyon, France. August 23-26, 2007.

F Mert Sasoglu, Devrim Kilinc, Kathleen Allen and Bradley Layton, IEEE Member

Drexel University, Department of Mechanical Engineering and Mechanics

Abstract: The primary goal of this work is to establish a robust, repeatable method for printing arrays of neurons. This work has two endpoints. One is to use a neural array as an experimental testbed for investigating neuronal cell growth hypotheses. The other endpoint is to enable the next generation of cell-based sensors. Herein we compare microcontact printing results previously published by our group with a new method of dip-pen printing. We present preliminary results for neurons growing on these microprinted arrays, assessing contact frequencies and growth characteristics.

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Nanopatterning using the BioForce Nano eNabler

NATO Advance Study Institute: Functionalized Nanoscale Materials, Devices, and Systems for Chem-Bio Sensors, Photonics, Energy Generation and Storage, Sinaia, Romania, June 4-15, 2007.

K.I. Arshak, O. Korostynska, and C. Cunniffe

Electronics and Computer Engineering Dept, University of Limerick, Ireland

Abstract. This paper discusses the opportunities, offered by novel nanopatterning facilities, namely, BioForce NanoeNablerTM (NeN), in the area of sensors development, with the focus on microsensor arrays for biological, environmental and medical fields. The NeN can deliver attolitre to picolitre volumes of liquid, such as small molecules, biomolecules, including proteins and nucleic acids, nanoparticles, reactive solutions and so forth, with a high degree of spatial accuracy. It is envisaged that the reduction in the sensors size would result in their new advanced functionalities.

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Microsensors Arrays Manufacture Using the Nano eNabler

8th IEEE Conference on Nanotechnology (IEEE NANO)

Arlington, TX, USA, August 18-21, 2008

O. Korostynska, K. Arshak, E. Gill, and A. Arshak

Microelectronics and Semiconductor Research Centre, University of Limerick, Ireland

Abstract.  Novel method for microarrays manufacture using BioForce NanoeNablerTM was successfully employed for developing sensors for biomedical applications, namely pH and glucose monitoring. It is envisaged that findings of this work would form the basis for miniaturised diagnostic system for a wide range of applications.

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