University of North Florida
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Stuart Chalk, Ph.D.
Department of Chemistry
University of North Florida
Phone: 1-904-620-1938
Fax: 1-904-620-3535
Email: schalk@unf.edu
Website: @unf

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Microelectronic Engineering

  • Publisher: Elsevier
  • FAD Code: MEEN
  • CODEN: MIENEF
  • ISSN: 0167-9317
  • Abbreviation: Microelectron. Eng.
  • DOI Prefix: 10.1016/j.mee,10.1016/0167-9317
  • Language: English
  • Comments: Fulltext from 1983 V1

Citations 9

"Biodynamical Analysis Microfluidic System"
Microelectron. Eng. 2006 Volume 83, Issue 4-9 Pages 1688-1691
Marioara Avram, Andrei Avram and Ciprian Iliescu

Abstract: The purpose of this research was to model, design and fabricate a biodynamic analysis microsystem required for determination of various molecular transport properties of the biological fluids. In order to achieve this, a lab-on-a-chip device was fabricated. The microchannel system developed satisfies the objectives for the study of microcirculation and the characterization of cell rheological properties, functions and behavior. The measurement principle of the viscosity of biological fluids is based on the detection of the rotation of a polysilicon gear wheels system. The gear wheels have external diameters of 250 µm, 200 µm, 160 µm and 3 µm thickness. The micromachining process combines the undercut and refill technique with pin-joint bearing permitting the fabrication of bushings that were used to elevate the rotor away from the silicon surface. The testing of the microfluidic dynamic system was performed using an electromagnetic micropump and a magnetic controller. Each device was fabricated by silicon micromachining technology and tested to obtain the specific characteristics.
Microfluidic

"A High Performance Microfluidic System Integrated With The Micropump And Microvalve On The Same Substrate"
Microelectron. Eng. 2006 Volume 83, Issue 4-9 Pages 1684-1687
Jong-Chul Yoo, Min-Chul Moon, Y.J. Choi, C.J. Kang and Yong-Sang Kim

Abstract: We present a microfluidic system with microvalves and a micropump that are easily integrated on the same substrate using the same fabrication process. The fabricated microfluidic system is suitable for use as a disposable device and its characteristics are optimized for use as a µchemical analysis system. The system is realized by means of a polydimethylsiloxane(PDMS)-glass chip and an indium tin oxide heater. We demonstrate the integration of the micropump and microvalves using a new thermopneumatic-actuated PDMS-based microfluidic system. A maximum pumping rate of about 730 nl/min is observed at a duty-ratio of 1% and a frequency of 2 Hz with a fixed power of 500 mW. The measured power at flow cut-off is 500 mW for the microvalve whose channel width, depth and membrane thickness were 400, 110 and 320 µm, respectively.

"Microfluidic Devices With Integrated Active Valves Based On Thermoplastic Elastomers"
Microelectron. Eng. 2006 Volume 83, Issue 4-9 Pages 1681-1683
Ivan Stoyanov, Michael Tewes, Michael Koch and Markus Löhndorf

Abstract: We have developed microfluidic devices with integrated active valves for an analytical biosensor system. Using polyurethane elastomers we obtained excellent sealing properties and very good chemical resistance against biological buffers and cleansing solutions. Pneumatically driven active valve structures have been integrated in the fluidic channels in order to reduce the sample volumes and to decrease the fluidic exchange times. The microfluidic devices have been fabricated by double-sided hot embossing and subsequent chemical bonding step for the fabrication of the closed channels and the valve structures. The design allows the immobilization of two different receptors on the same biochip with a 5 µl volume/sensor channel. The function of this microfluidic system with four integrated valves and two fluidic chambers has been successfully demonstrated in a bio-analytical measurement of binding of thrombin to its antibody.

"Diffusion Along Microfluidic Channels"
Microelectron. Eng. 2006 Volume 83, Issue 4-9 Pages 1669-1672
A. Heeren, C.P. Luo, G. Roth, A. Ganser, R. Brock, K.-H. Wiesmueller, W. Henschel and D.P. Kern

Abstract: Living cells respond simultaneously to a variety of different stimuli. Inside the cell the information emanating from different receptors is processed and integrated in molecular networks. For the specific modulation of such networks mixtures of stimuli or agents interfering with molecular activities are required. However, in order to identify optimum mixtures with respect to the identity of compounds and relative and absolute concentrations, large numbers of biological tests are required. Diffusion represents a highly efficient means for the generation of substance mixtures with a minimum of pipetting steps. Here, we present an array of microfluidic channels for the generation of substance mixtures with only two pipetting steps. A microfluidic structure with a height of 500 µm was fabricated. Diffusion was observed by fluorescence microscopy for fluorescein dissolved in water and the diffusion constant determined. Furthermore, a procedure to detect unwanted flow in the channels is developed.
Microfluidic Diffusion

"Response Of Super-paramagnetic Beads In Microfluidic Devices With Integrated Magnetic Micro-columns"
Microelectron. Eng. 2006 Volume 83, Issue 4-9 Pages 1655-1659
S.S. Guo, C.C. Zuo, W.H. Huang, C. Peroz and Y. Chen

Abstract: Ferromagnetic micro-columns (FMCs) have been fabricated on glass substrates using standard photolithography and electroplating and then integrated in micro-fluidic channels in order to study the response of super-paramagnetic beads suspended in an aqueous solution. We observed that under low external magnetic fields, the integrated micro-columns could generate sufficiently strong magnetic field gradients to trap super-paramagnetic beads in a flowing stream of water. The trapping behavior of the integrated FMCs was studied by considering different micro-patterns and different magnetic field intensities. In addition, the formation of magnetic micro-beads chains has been observed due to the magnetic dipole interactions. We believe that the integration of ferromagnetic micro-columns in micro-fluidic channels can have a variety of advanced applications, considering different possibilities of surface functionalization and manipulation of super-paramagnetic beads in an aqueous solution.
Microfluidic

"Free-standing Macroporous Silicon Membranes Over A Large Cavity For Filtering And Lab-on-chip Applications"
Microelectron. Eng. 2006 Volume 83, Issue 4-9 Pages 1421-1425
Dimitrios N. Pagonis and Androula G. Nassiopoulou

Abstract: This work presents a new electrochemical process for the formation of free-standing macroporous silicon membranes over a large cavity. The developed technique is based on a two-step electrochemical process of silicon dissolution, starting from thick macroPS membrane formation under the appropriate conditions and continuing with different anodization conditions that lead to formation of a nanoporous silicon layer underneath the macroporous membrane. The obtained structure is a double-layer of a macroporous over a nanoporous layer. By selective dissolution of the nanoporous layer, a free-standing macroporous silicon membrane over a large cavity in silicon is obtained. Interesting applications of this micromechanical structure include particle filtering and lab-on-chip devices.

"PDMS Microfluidic Chip With Integrated Waveguides For Optical Detection"
Microelectron. Eng. 2006 Volume 83, Issue 4-9 Pages 1291-1293
Markus Fleger and Andreas Neyer

Abstract: Recent activities in the field of optical detection on microfluidic chips suggest a variety of applications which can hardly be realised without integrated optical elements on chip. We here present a polydimethylsiloxane (PDMS) microfluidic chip with integrated waveguides as a high efficient optical detection system for the wavelength range 400-800 nm. The cheap material, the simple fabrication process based on microcasting of polysiloxane and short process times offer the option for a low cost mass production.

"Compact Micropumping System Based On LIGA Fabricated Microparts"
Microelectron. Eng. 2006 Volume 83, Issue 4-9 Pages 1288-1290
M. Matteucci, F. Pérenn&eagrave;s, B. Marmiroli, P. Miotti, L. Vaccari, A. Gosparini, A. Turchet and E. Di Fabrizio

Abstract: This report presents design, fabrication and testing of a magnetically actuated microgear pumps based on the LIGA technology. These micropumps exhibit flow rates between 0.5 and 8.5 ml/min and head pressures up to 100 cm-H2O. Geometries are determined for an optimal magnetic coupling, resulting in a linear behavior of the flow rate versus rotation speed.

"Reversible Assembling Of Microfluidic Devices By Aspiration"
Microelectron. Eng. 2006 Volume 83, Issue 4-9 Pages 1284-1287
M. Le Berre, C. Crozatier, G. Velve Casquillas and Y. Chen

Abstract: This paper deals with a novel and flexible method for microfluidic device assembling. In general, microfluidic device assembly is obtained by irreversible sealing with anodic, thermal or chemical bonding. Reversible assembly can be obtained by aspiration through a crossing channel network (CCN) between the two pieces of microfluidic device (channels and substrate). In this way, relatively high injection pressure can be achieved in microfluidic channels without leakage. We describe the principle and the fabrication of such PDMS devices and also show two examples of the described assembly method applied to surface functionalization.