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Development of new devices for toxin detection Carmen Moldovan, Rodica Iosub, Bogdan Firtat, Daniel Necula, *Eric Moore, *Gheorghe Marin IMT Bucharest *Tyndall National Institute, Cork Bucharest, 6 th of December Cooperation in FP7 Biomedical applications of micro and nanotechnologies Slide 2 Development of a toxin screening multi- parameter on-line biochip system. ToxiChip Proposal No. 27900 Bucharest, 6 th of December Cooperation in FP7 Biomedical applications of micro and nanotechnologies Slide 3 Alternative in-vitro testing methods for the monitoring of toxichemicals A eukaryote cell based biochip that examines the effects of toxichemicals on cell impedance, morphology, distribution and pH A panel of genetically engineered bacterial strains that optically report on the presence of toxichemicals that normally affect eukaryotic cells A prokaryote based biochip that uses optical analysis to measure the signal (fluorescence, bioluminescence) emitted by the bacteria in the presence of different toxichemicals Develop a microfluidic system with temperature control and pH sensor Toxichip Objective Bucharest, 6 th of December Cooperation in FP7 Biomedical applications of micro and nanotechnologies Slide 4 Comprise of finger electrodes composed of indium tin oxide (ITO) ITO will be used as an impedance sensor that allows real time non- invasive in-vitro analysis Biochip will function in a plug-in-play mode that will facilitate its insertion into the microfluidic platform Eukaryote cell-based biochip Inlet Outlet Dipstick Impedance sensor O-ring Solid Support Connector pH sensor Temperature sensor Bucharest, 6 th of December Cooperation in FP7 Biomedical applications of micro and nanotechnologies Slide 5 specialised interfaces that links the biochip to a PC, that record data and provides on-line continuous information on microfluidics, electro- chemical signals, temperature and pH Develop a management software for project experiments, such as data acquisition, parameters control and data mining Performance evaluation of the biochips will be done for the various integrated sensing capabilities - optical and electrochemical detection Characterise/Validate the biochips by using a combination of cellular bioassays and evaluating the biological effects of high doses and low doses, the impacts on DNA and endocrine perturbations on the bioassays. Further Objectives Bucharest, 6 th of December Cooperation in FP7 Biomedical applications of micro and nanotechnologies Slide 6 Participant no.Participant nameAbbreviation 1 (coordinator)Tyndall National InstituteTyndall 2Hebrew University of Jerusalem HUJ 3National Institute for Research and Development in Microtechnologies IMT 4Joint Research CentreJRC 5Tel Aviv UniversityTAU 6Scienion AGScienion 7Vigicell SASVigicell 8Istituto Superiore Mario BoellaISMB Bucharest, 6 th of December Cooperation in FP7 Biomedical applications of micro and nanotechnologies Slide 7 Microsystems research Simulation, design, technology, biosensors, electrodes for biological sensors, microprobes for recording of electrical activity of cells Technological development: - Micromachining techniques for silicon, glass and ceramics, -Immobilization technique of enzymes on electrodes -Spin deposition of thin film sensitive polymers National Institute for Research and Development in Microtechnologies (Romania) (Romania) Bucharest, 6 th of December Cooperation in FP7 Biomedical applications of micro and nanotechnologies Slide 8 + Biochip ElectrodeSurface Chemistry + Inverted Phase-contrast/Fluorescent Microscope coupled with CCD camera PC EIS Platform Interface Schematic of Toxichip Operating System + Cells Bucharest, 6 th of December Cooperation in FP7 Biomedical applications of micro and nanotechnologies Slide 9 Development of temperature sensor integrated with the microfluidic platform Simulation and design of the temperature sensor together with the microfluidic part where the sensor is integrated. Study of the compatibility of the sensor with the chemical aggressive working environment. Biocompatibility of the microsensor materials with the biological media. Experiments, manufacturing design and testing. Development of pH sensors integrated with the microfluidic platform Development of the pH sensor together with the microfluidic part where the sensor is positioned. Development of materials, manufacturing steps, experiments and testing. Bucharest, 6 th of December Cooperation in FP7 Biomedical applications of micro and nanotechnologies Slide 10 Three channels 1mmx1mm each Bucharest, 6 th of December Cooperation in FP7 Biomedical applications of micro and nanotechnologies Slide 11 1 channel flow Bucharest, 6 th of December Cooperation in FP7 Biomedical applications of micro and nanotechnologies Slide 12 3 channels flow Bucharest, 6 th of December Cooperation in FP7 Biomedical applications of micro and nanotechnologies Slide 13 2 mm x 2mm channels with enlarged areas (4 mmx2mm) hosting sensors and Cells (6mm exhaust) Mesh: Bucharest, 6 th of December Cooperation in FP7 Biomedical applications of micro and nanotechnologies Slide 14 Flow analysis Bucharest, 6 th of December Cooperation in FP7 Biomedical applications of micro and nanotechnologies Slide 15 Flow analysis (details) Bucharest, 6 th of December Cooperation in FP7 Biomedical applications of micro and nanotechnologies Slide 16 Analysis of the flow rate by square section channels Bucharest, 6 th of December Cooperation in FP7 Biomedical applications of micro and nanotechnologies Slide 17 Analysis of the flow rate by square section channels (one active entry detail) Bucharest, 6 th of December Cooperation in FP7 Biomedical applications of micro and nanotechnologies Slide 18 Flow rate analysis considering a round shape of the enlarged area hosting ITO electrode (three entries in the exhaust channel) Bucharest, 6 th of December Cooperation in FP7 Biomedical applications of micro and nanotechnologies Slide 19 Flow rate analysis considering a round shape of the enlarged area hosting ITO electrode (detail) Bucharest, 6 th of December Cooperation in FP7 Biomedical applications of micro and nanotechnologies Slide 20 Flow rate analysis considering a round shape of the enlarged area hosting ITO electrode (one entry in the exhaust channel) Bucharest, 6 th of December Cooperation in FP7 Biomedical applications of micro and nanotechnologies Slide 21 Flow rate analysis considering a round shape of the enlarged area hosting ITO electrode (one entry in the exhaust channel) - detail Bucharest, 6 th of December Cooperation in FP7 Biomedical applications of micro and nanotechnologies Slide 22 Flow rate analysis considering a round shape of the enlarged area hosting ITO electrode Bucharest, 6 th of December Cooperation in FP7 Biomedical applications of micro and nanotechnologies Slide 23 Flow rate analysis Bucharest, 6 th of December Cooperation in FP7 Biomedical applications of micro and nanotechnologies Slide 24 Technological flow microfluidic channels 1.Material PDMS 2.Patterning Laser machining Goal: study, set-up and optimisation of the microfluidic channels issues: design, technology, connections, integration into the platform Bucharest, 6 th of December Cooperation in FP7 Biomedical applications of micro and nanotechnologies Slide 25 Microfluidic channels Bucharest, 6 th of December Cooperation in FP7 Biomedical applications of micro and nanotechnologies Slide 26 Microfluidic channels Bucharest, 6 th of December Cooperation in FP7 Biomedical applications of micro and nanotechnologies Slide 27 pH Reference Temperature sensor Signal Processing Unit Sensors Unit Sensors cell Bucharest, 6 th of December Cooperation in FP7 Biomedical applications of micro and nanotechnologies Slide 28 Results: Design of the microfluidic platform Study of sensors, materials, technological versions; test structure utilisation Design of the sensors Interconnection layer design - draft Bucharest, 6 th of December Cooperation in FP7 Biomedical applications of micro and nanotechnologies Slide 29 Biosensors for neurotoxic substances detection The biosensors for neurotoxic substances will be developed as ISFET-type biosensors. The ISFET structure is represented by a concentration-potential transducer, with a biosensitive layer deposited on the gate (Acetylcholinesterases, immobilised on chitosane), which generates an interface potential on the gate. The enzymatic ISFET structure is developed in CMOS technology and the sensors response characteristics depend mainly on the AChE enzyme immobilisation mode. Optical photography of the sensor chip Bucharest, 6 th of December Cooperation in FP7 Biomedical applications of micro and nanotechnologies Slide 30 ISFET and chemoresistive sensors : The change in conductivity at the sensitive layer surface, deposited on top of the sensor. Principle: The change in conductivity at the sensitive layer surface, deposited on top of the sensor. The enzyme electrode is a combination of any electrochemical probe (amperometric, potentiometric or conductometric) with a thin layer (10 200mm) of immobilized enzyme. In these devices, the function of the enzyme is providing selectivity by virtue of its biological affinity for a particular substrate molecule. For example, an enzyme is capable of catalyzing a particular reaction of a given substrate even though other isomers of that substrate or similar substrates may be present Characterisation Bucharest, 6 th of December Cooperation in FP7 Biomedical applications of micro and nanotechnologies Slide 31 Bio integration I. Surface Chemistry Functionalization The silicon or glass substrates are functionalized as hydrophobic, hydrophilic, biocompatible surfaces Available procedures: Cleaning procedures Chemical Vapor Deposition: CVD, PSG, BPSG Polymer Adlayers: SU-8, Organosilanes (R n -Si-X(4-n)) Passivation (treatment in N 2 and H2) ( O NH NH C HO HO O O O n 2 2 ) H O C H H SiO 2 HH H -O O H H H H O H N H AChE SiO 2 Ex: After surface functionalization, the immobilised AChE enzyme within a chitosan biolayer laid on the sensor structure Immobilization technique Bucharest, 6 th of December Cooperation in FP7 Biomedical applications of micro and nanotechnologies Slide 32 Field effect gas sensors Field effect gas sensors are based on metal-insulator-semiconductor structures used to detect chemical quantities. Examples are biological and medical applications. The surface field effect is a desirable mechanism for a generating potential that provides high chemical selectivity and sensitivity. Using micromachining techniques we manufactured an ISFET device with posibility of integrating an area of sensing devices and the electronics on the same chip; ISFET sensors use the field effect transistors to detect very small quantities (10-3 g). Simulation and Layout of a FET sensor on the tip of a microprobe Bucharest, 6 th of December Cooperation in FP7 Biomedical applications of micro and nanotechnologies Slide 33 II. Deposition and characterization of biological materials Deposition Plotter (OmniGrid Micro): Biological materials deposition for biosensors manufacturing Characterization Scanner (GeneTAC UC4 Microarray scanner) Immobilized enzyme on gold electrodes Enzyme based biosensor Enzyme based biosensor (fluorescence) Bucharest, 6 th of December Cooperation in FP7 Biomedical applications of micro and nanotechnologies Slide 34 III. Biosensors - Devices design and fabrication including masks processing Microelectrodes to be deposited with biomaterials IMT can provide a wide range of microelectrodes design and manufacturing, for biomaterials applications. The microelectrodes can be deposited and configured on silicon substrates in our technological facilities. ISFET sensor for ions detection in biological media The surface field effect is a desirable mechanism for a generating potential that provides high chemical selectivity and sensitivity. The ISFET is essentially an extended gate field effect transistor with the surface of the transistor and the reference electrode. ISFET sensor placed on a thin tip to be inserted in small liquid media Example of microelectrodes layout, for biomaterials applications Bucharest, 6 th of December Cooperation in FP7 Biomedical applications of micro and nanotechnologies Slide 35 Microfluidics devices development: design, simulations, manufacturing Design and simulations for microfluidics devices, including general flow, thermal, fluid mixing, electrokinetic, chemical reactions, etc. Bucharest, 6 th of December Cooperation in FP7 Biomedical applications of micro and nanotechnologies Slide 36 THANK YOU! The paper is presenting the result of two projects: Toxichip, IST, STREP Toxisystem, Romanian Security Programme Bucharest, 6 th of December Cooperation in FP7 Biomedical applications of micro and nanotechnologies