http://www.mdpi.com/journal/sensors/special_issues/state-of-the-art-denmark/ {snippet name="submission_info"} http://www.mdpi.com/1424-8220/10/12/11352/ A single lipid vesicle can be regarded as an autonomous ultra-miniaturised 3D biomimetic “scaffold” (Ø ≥ 13 nm) ideally suited for reconstitution and interrogation of biochemical processes. The enclosing lipid bilayer membrane of a vesicle can be applied for studying binding (protein/lipid or receptor/ligand interactions) or transmembrane events (membrane permeability or ion channel activation) while the aqueous vesicle lumen can be used for confining few or single macromolecules and probe, e.g., protein folding, catalytic pathways of enzymes or more complex biochemical reactions, such as signal transduction cascades. Immobilisation (arraying) of single vesicles on a solid support is an extremely useful technique that allows detailed characterisation of vesicle preparations using surface sensitive techniques, in particular fluorescence microscopy. Surface-based single vesicle arrays allow a plethora of prototypic sensing applications in a high throughput format with high spatial and high temporal resolution. In this review we present a series of applications of single vesicle arrays for screening/sensing of: membrane curvature dependent protein-lipid interactions, bilayer tension, reactions triggered in the vesicle lumen, the activity of transmembrane protein channels and biological membrane fusion reactions. http://www.mdpi.com/1424-8220/10/12/11352/ Mon, 13 Dec 2010 00:00:00 CET Sensors 2010-12-13 10 12 Review 11352 11368 1424-8220 Sensing-Applications of Surface-Based Single Vesicle Arrays 2010-12-13 doi: 10.3390/s101211352 Sune M. Christensen Dimitrios G. Stamou http://www.mdpi.com/1424-8220/10/12/10986/ Conducting polymer 3D microelectrodes have been fabricated for possible future neurological applications. A combination of micro-fabrication techniques and chemical polymerization methods has been used to create pillar electrodes in polyaniline and polypyrrole. The thin polymer films obtained showed uniformity and good adhesion to both horizontal and vertical surfaces. Electrodes in combination with metal/conducting polymer materials have been characterized by cyclic voltammetry and the presence of the conducting polymer film has shown to increase the electrochemical activity when compared with electrodes coated with only metal. An electrochemical characterization of gold/polypyrrole electrodes showed exceptional electrochemical behavior and activity. PC12 cells were finally cultured on the investigated materials as a preliminary biocompatibility assessment. These results show that the described electrodes are possibly suitable for future in-vitro neurological measurements. http://www.mdpi.com/1424-8220/10/12/10986/ Fri, 03 Dec 2010 00:00:00 CET Sensors 2010-12-03 10 12 Article 10986 11000 1424-8220 Conducting Polymer 3D Microelectrodes 2010-12-03 doi: 10.3390/s101210986 Luigi Sasso Patricia Vazquez † Indumathi Vedarethinam Jaime Castillo-León Jenny Emnéus Winnie E. Svendsen http://www.mdpi.com/1424-8220/10/11/10339/ In this paper we discuss the fabrication and characterization of three dimensional (3D) micro- and nanoelectrodes with the goal of using them for extra- and intracellular studies. Two different types of electrodes will be described: high aspect ratio microelectrodes for studying the communication between cells and ultimately for brain slice recordings and small nanoelectrodes for highly localized measurements and ultimately for intracellular studies. Electrical and electrochemical characterization of these electrodes as well as the results of PC12 cell differentiation on chip will be presented and discussed. http://www.mdpi.com/1424-8220/10/11/10339/ Wed, 17 Nov 2010 00:00:00 CET Sensors 2010-11-17 10 11 Article 10339 10355 1424-8220 Fabrication and Characterization of 3D Micro- and Nanoelectrodes for Neuron Recordings 2010-11-17 doi: 10.3390/s101110339 Maria Dimaki Patricia Vazquez Mark Holm Olsen Luigi Sasso Romen Rodriguez-Trujillo Indumathi Vedarethinam Winnie E. Svendsen http://www.mdpi.com/1424-8220/10/11/9831/ Fluorescence in situ Hybridization (FISH) is a major cytogenetic technique for clinical genetic diagnosis of both inherited and acquired chromosomal abnormalities. Although FISH techniques have evolved and are often used together with other cytogenetic methods like CGH, PRINS and PNA-FISH, the process continues to be a manual, labour intensive, expensive and time consuming technique, often taking over 3–5 days, even in dedicated labs. We have developed a novel microFISH device to perform metaphase FISH on a chip which overcomes many shortcomings of the current laboratory protocols. This work also introduces a novel splashing device for preparing metaphase spreads on a microscope glass slide, followed by a rapid adhesive tape-based bonding protocol leading to rapid fabrication of the microFISH device. The microFISH device allows for an optimized metaphase FISH protocol on a chip with over a 20-fold reduction in the reagent volume. This is the first demonstration of metaphase FISH on a microfluidic device and offers a possibility of automation and significant cost reduction of many routine diagnostic tests of genetic anomalies. http://www.mdpi.com/1424-8220/10/11/9831/ Tue, 02 Nov 2010 00:00:00 CET Sensors 2010-11-02 10 11 Article 9831 9846 1424-8220 Metaphase FISH on a Chip: Miniaturized Microfluidic Device for Fluorescence in situ Hybridization 2010-11-02 doi: 10.3390/s101109831 Indumathi Vedarethinam Pranjul Shah Maria Dimaki Zeynep Tumer Niels Tommerup Winnie E. Svendsen http://www.mdpi.com/1424-8220/10/11/9541/ In the framework of developing innovative microfabricated pressure sensors, we present here three designs based on different readout principles, each one tailored for a specific application. A touch mode capacitive pressure sensor with high sensitivity (14 pF/bar), low temperature dependence and high capacitive output signal (more than 100 pF) is depicted. An optical pressure sensor intrinsically immune to electromagnetic interference, with large pressure range (0–350 bar) and a sensitivity of 1 pm/bar is presented. Finally, a resonating wireless pressure sensor power source free with a sensitivity of 650 KHz/mmHg is described. These sensors will be related with their applications in  harsh environment, distributed systems and medical environment, respectively. For many aspects, commercially available sensors, which in vast majority are piezoresistive, are not suited for the applications proposed. http://www.mdpi.com/1424-8220/10/11/9541/ Thu, 28 Oct 2010 00:00:00 CEST Sensors 2010-10-28 10 11 Article 9541 9563 1424-8220 Novel Designs for Application Specific MEMS Pressure Sensors 2010-10-28 doi: 10.3390/s101109541 Giulio Fragiacomo Kasper Reck Lasse Lorenzen Erik V. Thomsen http://www.mdpi.com/1424-8220/10/3/2348/ A refractive index sensor has been fabricated in silicon oxynitride by standard UV lithography and dry etching processes. The refractive index sensor consists of a 1D photonic crystal (PhC) embedded in a microfluidic channel addressed by fiber-terminated planar waveguides. Experimental demonstrations performed with several ethanol solutions ranging from a purity of 96.00% (n = 1.36356) to 95.04% (n = 1.36377) yielded a sensitivity (Δλ/Δn) of 836 nm/RIU and a limit of detection (LOD) of 6 x 10-5 RIU, which is, however, still one order of magnitude higher than the theoretical lower limit of the limit of detection 1.3 x 10–6 RIU. http://www.mdpi.com/1424-8220/10/3/2348/ Mon, 22 Mar 2010 00:00:00 CET Sensors 2010-03-22 10 3 Article 2348 2358 1424-8220 Refractive Index Sensor Based on a 1D Photonic Crystal in a Microfluidic Channel 2010-03-22 doi: 10.3390/s100302348 Nunes Mortensen Kutter Mogensen