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Sabourin D, Skafte-Pedersen P, Søe MJ, Hemmingsen M, Alberti M, Coman V, Petersen J, Emnéus J, Kutter JP, Snakenborg D, Jørgensen F, Clausen C, Holmstrøm K, Dufva M. The MainSTREAM component platform: a holistic approach to microfluidic system design. ACTA ACUST UNITED AC 2012; 18:212-28. [PMID: 23015520 DOI: 10.1177/2211068212461445] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
A microfluidic component library for building systems driving parallel or serial microfluidic-based assays is presented. The components are a miniaturized eight-channel peristaltic pump, an eight-channel valve, sample-to-waste liquid management, and interconnections. The library of components was tested by constructing various systems supporting perfusion cell culture, automated DNA hybridizations, and in situ hybridizations. The results showed that the MainSTREAM components provided (1) a rapid, robust, and simple method to establish numerous fluidic inputs and outputs to various types of reaction chips; (2) highly parallel pumping and routing/valving capability; (3) methods to interface pumps and chip-to-liquid management systems; (4) means to construct a portable system; (5) reconfigurability/flexibility in system design; (6) means to interface to microscopes; and (7) compatibility with tested biological methods. It was found that LEGO Mindstorms motors, controllers, and software were robust, inexpensive, and an accessible choice as compared with corresponding custom-made actuators. MainSTREAM systems could operate continuously for weeks without leaks, contamination, or system failures. In conclusion, the MainSTREAM components described here meet many of the demands on components for constructing and using microfluidics systems.
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Affiliation(s)
- David Sabourin
- DTU Nanotech, Dept. of Micro- and Nanotechnology, Technical University of Denmark, Kgs. Lyngby, Denmark
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Lafleur JP, Snakenborg D, Nielsen SS, Møller M, Toft KN, Menzel A, Jacobsen JK, Vestergaard B, Arleth L, Kutter JP. Automated microfluidic sample-preparation platform for high-throughput structural investigation of proteins by small-angle X-ray scattering. J Appl Crystallogr 2011. [DOI: 10.1107/s0021889811030068] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022] Open
Abstract
A new microfluidic sample-preparation system is presented for the structural investigation of proteins using small-angle X-ray scattering (SAXS) at synchrotrons. The system includes hardware and software features for precise fluidic control, sample mixing by diffusion, automated X-ray exposure control, UV absorbance measurements and automated data analysis. As little as 15 µl of sample is required to perform a complete analysis cycle, including sample mixing, SAXS measurement, continuous UV absorbance measurements, and cleaning of the channels and X-ray cell with buffer. The complete analysis cycle can be performed in less than 3 min. Bovine serum albumin was used as a model protein to characterize the mixing efficiency and sample consumption of the system. The N2 fragment of an adaptor protein (p120-RasGAP) was used to demonstrate how the device can be used to survey the structural space of a protein by screening a wide set of conditions using high-throughput techniques.
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Laczka O, Maesa JM, Godino N, del Campo J, Fougt-Hansen M, Kutter JP, Snakenborg D, Muñoz-Pascual FX, Baldrich E. Improved bacteria detection by coupling magneto-immunocapture and amperometry at flow-channel microband electrodes. Biosens Bioelectron 2011; 26:3633-40. [PMID: 21392960 DOI: 10.1016/j.bios.2011.02.019] [Citation(s) in RCA: 59] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2010] [Revised: 01/13/2011] [Accepted: 02/12/2011] [Indexed: 11/24/2022]
Abstract
This paper describes the first immunosensing system reported for the detection of bacteria combining immunomagnetic capture and amperometric detection in a one-step sandwich format, and in a microfluidic environment. Detection is based on the electrochemical monitoring of the activity of horseradish peroxidase (HRP), an enzyme label, through its catalysis of hydrogen peroxide (H(2)O(2)) in the presence of the mediator hydroquinone (HQ). The enzymatic reaction takes place in an incubation micro-chamber where the magnetic particles (MPs) are confined, upstream from the working electrode. The enzyme product is then pumped along a microchannel, where it is amperometrically detected by a set of microelectrodes. This design avoids direct contact of the biocomponents with the electrode, which lowers the risk of electrode fouling. The whole assay can be completed in 1h. The experiments performed with Escherichia coli evidenced a linear response for concentrations ranging 10(2)-10(8) cell ml(-1), with a limit of detection of 55 cells ml(-1) in PBS, without pre-enrichment steps. Furthermore, 100 cells ml(-1) could be detected in milk, and with negligible interference by non-target bacteria such as Pseudomonas.
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Affiliation(s)
- Olivier Laczka
- Institut de Microelectrònica de Barcelona (IMB-CNM), CSIC, Campus Universitat Autònoma de Barcelona, 08193 - Bellaterra, Barcelona, Spain
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Musa AE, del Campo FJ, Abramova N, Alonso-Lomillo MA, Domínguez-Renedo O, Arcos-Martínez MJ, Brivio M, Snakenborg D, Geschke O, Kutter JP. Disposable Miniaturized Screen-Printed pH and Reference Electrodes for Potentiometric Systems. ELECTROANAL 2010. [DOI: 10.1002/elan.201000443] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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Petersen NJ, Foss ST, Jensen H, Hansen SH, Skonberg C, Snakenborg D, Kutter JP, Pedersen-Bjergaard S. On-Chip Electro Membrane Extraction with Online Ultraviolet and Mass Spectrometric Detection. Anal Chem 2010; 83:44-51. [DOI: 10.1021/ac1027148] [Citation(s) in RCA: 84] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Nickolaj Jacob Petersen
- Department of Pharmaceutics and Analytical Chemistry, Faculty of Pharmaceutical Sciences, University of Copenhagen, DK-2100 Copenhagen, Denmark, School of Pharmacy, University of Oslo, Post Office Box 1068 Blindern, 0316 Oslo, Norway, and Department of Micro- and Nanotechnology, Technical University of Denmark, 2800 Lyngby, Denmark
| | - Sunniva Taule Foss
- Department of Pharmaceutics and Analytical Chemistry, Faculty of Pharmaceutical Sciences, University of Copenhagen, DK-2100 Copenhagen, Denmark, School of Pharmacy, University of Oslo, Post Office Box 1068 Blindern, 0316 Oslo, Norway, and Department of Micro- and Nanotechnology, Technical University of Denmark, 2800 Lyngby, Denmark
| | - Henrik Jensen
- Department of Pharmaceutics and Analytical Chemistry, Faculty of Pharmaceutical Sciences, University of Copenhagen, DK-2100 Copenhagen, Denmark, School of Pharmacy, University of Oslo, Post Office Box 1068 Blindern, 0316 Oslo, Norway, and Department of Micro- and Nanotechnology, Technical University of Denmark, 2800 Lyngby, Denmark
| | - Steen Honoré Hansen
- Department of Pharmaceutics and Analytical Chemistry, Faculty of Pharmaceutical Sciences, University of Copenhagen, DK-2100 Copenhagen, Denmark, School of Pharmacy, University of Oslo, Post Office Box 1068 Blindern, 0316 Oslo, Norway, and Department of Micro- and Nanotechnology, Technical University of Denmark, 2800 Lyngby, Denmark
| | - Christian Skonberg
- Department of Pharmaceutics and Analytical Chemistry, Faculty of Pharmaceutical Sciences, University of Copenhagen, DK-2100 Copenhagen, Denmark, School of Pharmacy, University of Oslo, Post Office Box 1068 Blindern, 0316 Oslo, Norway, and Department of Micro- and Nanotechnology, Technical University of Denmark, 2800 Lyngby, Denmark
| | - Detlef Snakenborg
- Department of Pharmaceutics and Analytical Chemistry, Faculty of Pharmaceutical Sciences, University of Copenhagen, DK-2100 Copenhagen, Denmark, School of Pharmacy, University of Oslo, Post Office Box 1068 Blindern, 0316 Oslo, Norway, and Department of Micro- and Nanotechnology, Technical University of Denmark, 2800 Lyngby, Denmark
| | - Jörg P. Kutter
- Department of Pharmaceutics and Analytical Chemistry, Faculty of Pharmaceutical Sciences, University of Copenhagen, DK-2100 Copenhagen, Denmark, School of Pharmacy, University of Oslo, Post Office Box 1068 Blindern, 0316 Oslo, Norway, and Department of Micro- and Nanotechnology, Technical University of Denmark, 2800 Lyngby, Denmark
| | - Stig Pedersen-Bjergaard
- Department of Pharmaceutics and Analytical Chemistry, Faculty of Pharmaceutical Sciences, University of Copenhagen, DK-2100 Copenhagen, Denmark, School of Pharmacy, University of Oslo, Post Office Box 1068 Blindern, 0316 Oslo, Norway, and Department of Micro- and Nanotechnology, Technical University of Denmark, 2800 Lyngby, Denmark
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Godino N, del Campo FJ, Muñoz FX, Hansen MF, Kutter JP, Snakenborg D. Integration of a zero dead-volume PDMS rotary switch valve in a miniaturised (bio)electroanalytical system. Lab Chip 2010; 10:1841-1847. [PMID: 20449514 DOI: 10.1039/c003000g] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/29/2023]
Abstract
This work features the design, fabrication and characterisation of a miniaturised electroanalytical lab on a chip that allows the performance of a complete bioassay, from the capture of magnetic particles through their functionalisation and sample incubation to the detection of electroactive reaction products. The system is built using mainly polymeric materials such as PMMA and PDMS and fast prototyping techniques such as milling and moulding. The system also includes a set of microelectrodes, photo-lithographed on a silicon chip. The novelty lies in the design of the rotary microvalve, which contains a microreactor so that various reaction and incubation steps can be carried out in isolation from the detection event with zero dead volume. This avoids contamination and fouling of the electrodes by proteins or other organic matter, and extends the useful lifetime of the detector. The system operation is demonstrated by a model example, consisting in the functionalisation of streptavidin-coated magnetic particles with biotinylated beta-galactosidase over periods ranging from 5 to 15 min, at which point the particles saturate. Although the system is intended for the development of enzyme-based electrochemical bioassays, the concept of its rotary microreactor can be applied more broadly.
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Affiliation(s)
- Neus Godino
- Instituto de Microelectrónica de Barcelona, IMB-CNM (CSIC), Esfera UAB, Campus Universitat Autónoma de Barcelona, 08193 Bellaterra, Barcelona, Spain
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Illa X, Ordeig O, Snakenborg D, Romano-Rodríguez A, Compton RG, Kutter JP. A cyclo olefin polymer microfluidic chip with integrated gold microelectrodes for aqueous and non-aqueous electrochemistry. Lab Chip 2010; 10:1254-1261. [PMID: 20445877 DOI: 10.1039/b926737a] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/29/2023]
Abstract
This paper presents an entirely polymeric microfluidic system, made of cyclo olefin polymer (COP), with integrated gold microband electrodes for electrochemical applications in organic media. In the present work, we take advantage of the COP's high chemical stability to polar organic solvents in two different ways: (i) to fabricate gold microelectrodes using COP as a substrate by standard lithographic and lift-off techniques; and (ii) to perform electrochemical experiments in organic media. In particular, fourteen parallel gold microelectrodes with a width of 14 microm and separated from their closest neighbour by 16 microm were fabricated by lithographic and lift-off techniques on a 188 microm thick COP sheet. A closed channel configuration was obtained by pressure-assisted thermal bonding between the COP sheet containing the microelectrodes and a microstructured COP sheet, where a 3 cm long, 50 microm wide and 24 microm deep channel was fabricated via hot embossing. Cyclic voltammetric measurements were carried out in aqueous and organic media, using a solution consisting of 5 mM ferrocyanide/ferricyanide in 0.5 M KNO(3) and 5 mM ferrocene in 0.1 M TBAP/acetonitrile, respectively. Experimental currents obtained for different flow rates ranging from 1 to 10 microL min(-1) were compared to the theoretical steady state currents calculated by the Levich equation for a band electrode (R. G. Compton, A. C. Fisher, R. G. Wellington, P. J. Dobson and P. A. Leigh, J. Phys. Chem., 1993, 97, 10410-10415). In both cases, the difference between the experimental and the predicted data is less than 5%, thus validating the behaviour of the fabricated device. This result opens the possibility to use a microfluidic system made entirely from COP with integrated microband electrodes in organic electroanalysis and in electrosynthesis.
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Affiliation(s)
- Xavi Illa
- Universitat de Barcelona, MIND-IN(2)UB Department of Electronics, Barcelona, Spain.
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Slater C, Cleary J, Lau KT, Snakenborg D, Corcoran B, Kutter JP, Diamond D. Validation of a fully autonomous phosphate analyser based on a microfluidic lab-on-a-chip. Water Sci Technol 2010; 61:1811-1818. [PMID: 20371940 DOI: 10.2166/wst.2010.069] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/29/2023]
Abstract
This work describes the design of a phosphate analyser that utilises a microfluidic lab-on-a-chip. The analyser contains all the required chemical storage, pumping and electronic components to carry out a complete phosphate assay. The system is self-calibrating and self-cleaning, thus capable of long-term operation. This was proven by a bench top calibration of the analyser using standard solutions and also by comparing the analyser's performance to a commercially available phosphate monitor installed at a waste water treatment plant. The output of the microfluidic lab-on-a-chip analyser was shown to have sensitivity and linear range equivalent to the commercially available monitor and also the ability to operate over an extended period of time.
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Affiliation(s)
- C Slater
- CLARITY: Centre for Sensor Web Technologies, Dublin City University, Dublin, Ireland.
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Skafte-Pedersen P, Sabourin D, Dufva M, Snakenborg D. Multi-channel peristaltic pump for microfluidic applications featuring monolithic PDMS inlay. Lab Chip 2009; 9:3003-6. [PMID: 19789757 DOI: 10.1039/b906156h] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
The design, fabrication and characterization of a miniaturized, mechanically-actuated 12-channel peristaltic pump for microfluidic applications and built from simple, low-cost materials and fabrication methods is presented. Two pump configurations are tested, including one which reduces pulsating flow. Both use a monolithic PDMS pumping inlay featuring three-dimensional geometries favourable to pumping applications and 12 wholly integrated circular channels. Flow rates in the sub-microL min(-1) to microL min(-1) range were obtained. Channel-to-channel flow rate variability was comparable to a commercial pumping system at lower flow rates. The small footprint, 40 mm by 80 mm, of the micropump renders it portable, and allows its use on microscope stages adjacent to microfluidic devices, thus reducing system dead volumes. The micropump's design allows potential use in remote and resource-limited locations.
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Affiliation(s)
- Peder Skafte-Pedersen
- Department of Micro- and Nanotechnology, Technical University of Denmark, DTU Nanotech, Building 345 East, DK-2800, Kongens, Lyngby, Denmark
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10
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Nielsen SS, Toft KN, Snakenborg D, Jeppesen MG, Jacobsen JK, Vestergaard B, Kutter JP, Arleth L. BioXTAS RAW, a software program for high-throughput automated small-angle X-ray scattering data reduction and preliminary analysis. J Appl Crystallogr 2009. [DOI: 10.1107/s0021889809023863] [Citation(s) in RCA: 180] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
Abstract
A fully open source software program for automated two-dimensional and one-dimensional data reduction and preliminary analysis of isotropic small-angle X-ray scattering (SAXS) data is presented. The program is freely distributed, following the open-source philosophy, and does not rely on any commercial software packages.BioXTAS RAWis a fully automated program that,viaan online feature, reads raw two-dimensional SAXS detector output files and processes and plots data as the data files are created during measurement sessions. The software handles all steps in the data reduction. This includes mask creation, radial averaging, error bar calculation, artifact removal, normalization andqcalibration. Further data reduction such as background subtraction and absolute intensity scaling is fast and easyviathe graphical user interface.BioXTAS RAWalso provides preliminary analysis of one-dimensional data in terms of the indirect Fourier transform using the objective Bayesian approach to obtain the pair-distance distribution function, PDDF, and is thereby a free and open-source alternative to existing PDDF estimation software. Apart from the TIFF input format, the program also accepts ASCII-format input files and is currently compatible with one-dimensional data files from SAXS beamlines at a number of synchrotron facilities.BioXTAS RAWis written in Python with C++ extensions.
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Poulsen L, Søe MJ, Snakenborg D, Møller LB, Dufva M. Multi-stringency wash of partially hybridized 60-mer probes reveals that the stringency along the probe decreases with distance from the microarray surface. Nucleic Acids Res 2008; 36:e132. [PMID: 18805905 PMCID: PMC2582620 DOI: 10.1093/nar/gkn600] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/05/2022] Open
Abstract
Here, we describe a multi-parametric study of DNA hybridization to probes with 20–70% G + C content. Probes were designed towards 71 different sites/mutations in the phenylalanine hydroxylase gene. Seven probe lengths, three spacer lengths and six stringencies were systematically varied. The three spacer lengths were obtained by placing the gene-specific sequence in discrete steps along the 60-mer probes. The study was performed using Agilent 8 × 15 000 probes custom-made arrays and a home-built array washer providing different stringencies to each of the eight sub-arrays on the slides. Investigation of hybridization signals, specificity and dissociation curves indicated that probes close to the surface were influenced by an additional stringency provided by the microarray surface. Consistent with this, probes close to the surface required 4 × SSC, while probes placed away from the surface required 0.35 × SSC wash buffers in order to give accurate genotyping results. Multiple step dissociation was frequently observed for probes placed furthest away from surface, but not for probes placed proximal to the surface, which is consistent with the hypothesis that there is different stringency along the 60-mer. The results have impact on design of probes for genotyping, gene expression and comparative genome hybridization analysis.
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Affiliation(s)
- Lena Poulsen
- DTU Nanotech, Department of Micro and Nanotechnology, Technical University of Denmark, Oersteds Plads, Bld. 345 East, DK-2800 Lyngby, Denmark
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Toft KN, Vestergaard B, Nielsen SS, Snakenborg D, Jeppesen MG, Jacobsen JK, Arleth L, Kutter JP. High-Throughput Small Angle X-ray Scattering from Proteins in Solution Using a Microfluidic Front-End. Anal Chem 2008; 80:3648-54. [DOI: 10.1021/ac800011y] [Citation(s) in RCA: 75] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- K. Nørgaard Toft
- Departments of Medicinal Chemistry and Natural Sciences, University of Copenhagen, Denmark, Department of Micro- and Nanotechnology, Technical University of Denmark, Denmark, and Novo Nordisk A/S, Denmark
| | - Bente Vestergaard
- Departments of Medicinal Chemistry and Natural Sciences, University of Copenhagen, Denmark, Department of Micro- and Nanotechnology, Technical University of Denmark, Denmark, and Novo Nordisk A/S, Denmark
| | - Søren S. Nielsen
- Departments of Medicinal Chemistry and Natural Sciences, University of Copenhagen, Denmark, Department of Micro- and Nanotechnology, Technical University of Denmark, Denmark, and Novo Nordisk A/S, Denmark
| | - Detlef Snakenborg
- Departments of Medicinal Chemistry and Natural Sciences, University of Copenhagen, Denmark, Department of Micro- and Nanotechnology, Technical University of Denmark, Denmark, and Novo Nordisk A/S, Denmark
| | - Mads G. Jeppesen
- Departments of Medicinal Chemistry and Natural Sciences, University of Copenhagen, Denmark, Department of Micro- and Nanotechnology, Technical University of Denmark, Denmark, and Novo Nordisk A/S, Denmark
| | - Jes K. Jacobsen
- Departments of Medicinal Chemistry and Natural Sciences, University of Copenhagen, Denmark, Department of Micro- and Nanotechnology, Technical University of Denmark, Denmark, and Novo Nordisk A/S, Denmark
| | - Lise Arleth
- Departments of Medicinal Chemistry and Natural Sciences, University of Copenhagen, Denmark, Department of Micro- and Nanotechnology, Technical University of Denmark, Denmark, and Novo Nordisk A/S, Denmark
| | - Jörg P. Kutter
- Departments of Medicinal Chemistry and Natural Sciences, University of Copenhagen, Denmark, Department of Micro- and Nanotechnology, Technical University of Denmark, Denmark, and Novo Nordisk A/S, Denmark
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Balslev S, Jorgensen AM, Bilenberg B, Mogensen KB, Snakenborg D, Geschke O, Kutter JP, Kristensen A. Lab-on-a-chip with integrated optical transducers. Lab Chip 2006; 6:213-7. [PMID: 16450030 DOI: 10.1039/b512546d] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/06/2023]
Abstract
Taking the next step from individual functional components to higher integrated devices, we present a feasibility study of a lab-on-a-chip system with five different components monolithically integrated on one substrate. These five components represent three main domains of microchip technology: optics, fluidics and electronics. In particular, this device includes an on-chip optically pumped liquid dye laser, waveguides and fluidic channels with passive diffusive mixers, all defined in one layer of SU-8 polymer, as well as embedded photodiodes in the silicon substrate. The dye laser emits light at 576 nm, which is directly coupled into five waveguides that bring the light to five different locations along a fluidic channel for absorbance measurements. The transmitted portion of the light is collected at the other side of this cuvette, again by waveguides, and finally detected by the photodiodes. Electrical read-out is accomplished by integrated metal connectors. To our knowledge, this is the first time that integration of all these components has been demonstrated.
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Affiliation(s)
- S Balslev
- MIC - Department of Micro and Nanotechnology Technical University of Denmark (DTU) Oersteds Plads, Building 345 east, DK-2800, Kongens Lyngby, Denmark
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Brask A, Snakenborg D, Kutter JP, Bruus H. AC electroosmotic pump with bubble-free palladium electrodes and rectifying polymer membrane valves. Lab Chip 2006; 6:280-8. [PMID: 16450039 DOI: 10.1039/b509997h] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/06/2023]
Abstract
We present the design, test and theoretical analysis of a novel micropump. The purpose is to make a pump with large flow rate (approximately 10 microL min-1) and high pressure capacity (approximately 1 bar) powered by a low voltage DeltaV<30 V. The pump is operated in AC mode with an electroosmotic actuator in connection with a full wave rectifying valve system. Individual valves are based on a flexible membrane with a slit. Bubble-free palladium electrodes are implemented in order to increase the range of applications and reduce maintenance.
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Affiliation(s)
- Anders Brask
- MIC-Department of Micro and Nanotechnology Technical University of Denmark, DTU bldg. 345 east, DK-2800, Kongens Lyngby, Denmark
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Wang Z, El-Ali J, Engelund M, Gotsaed T, Perch-Nielsen IR, Mogensen KB, Snakenborg D, Kutter JP, Wolff A. Measurements of scattered light on a microchip flow cytometer with integrated polymer based optical elements. Lab Chip 2004; 4:372-7. [PMID: 15269807 DOI: 10.1039/b400663a] [Citation(s) in RCA: 86] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/20/2023]
Abstract
Flow cytometry is widely used for analyzing microparticles, such as cells and bacteria. In this paper, we report an innovative microsystem, in which several different optical elements (waveguides, lens and fiber-to-waveguide couplers) are integrated with microfluidic channels to form a complete microchip flow cytometer. All the optical elements, the microfluidic system, and the fiber-to-waveguide couplers were defined in one layer of polymer (SU-8, negative photoresist) by standard photolithography. With only a single mask procedure required, all the fabrication and packaging processes can be finished in one day. Polystyrene beads were measured in the microchip flow cytometer, and three signals (forward scattering, large angle scattering and extinction) were measured simultaneously for each bead. To our knowledge this is the first time forward scattered light and incident light extinction were measured in a microsystem using integrated optics. The microsystem can be applied for analyzing different kinds of particles and cells, and can easily be integrated with other microfluidic components.
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Affiliation(s)
- Z Wang
- MIC-Dept. of Micro and Nanotechnology, Technical University of Denmark, Building 345e, DK-2800 Kgs, Lyngby, Denmark.
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