Low-cost and Chemical Resistant Microfluidic Devices Based on Thermoplastic Elastomers for a Novel Biosensor System
- PDF / 204,922 Bytes
- 6 Pages / 612 x 792 pts (letter) Page_size
- 63 Downloads / 208 Views
J11.4.1
Low-cost and chemical resistant microfluidic devices based on thermoplastic elastomers for a novel biosensor system I. Stoyanov, M. Tewes, S. Glass, M. Koch and M. Löhndorf center of advanced european studies and research (caesar), Ludwig-Erhard-Allee 2, D-53175 Bonn, Germany.
ABSTRACT Low-cost and chemical resistant microfluidic devices based on thermoplastic elastomers have been fabricated by hot embossing technology. Commercial available thermoplastic elastomer foils based on polyurethane (PU) in a thickness range of 100-600 µm have been used. Prior to the fabrication of the microfluidic devices the chemical resistance of the material against a wide range of standard biological buffer solutions and solvents had been analysed. We created systems of channels, reservoirs and holes for the connections to external capillaries by double-sided hot embossing with an alignment accuracy of +/- 3 micrometer. Closed channel structures were produced by an additional chemical bonding process of the embossed devices with another thermoplastic elastomer foil. The total volume of the fluidic cell was 2 µl/sensor for the use with SAW (surface-acoustic wave) sensor chip and about 0.2 µl/sensor for the impedance sensors. A novel multi-chamber fluidic device was successfully tested for in-situ immobilization of thrombin antibodies and Bovin Serum Albumin (BSA) on different sensor elements of the same sensor chip.
INTRODUCTION An important part of the development of a complete analytical biosensor system is the technology for the functional integration of the fluidic components and the sensor device (worldto-chip interface). We have developed a modular biosensor system where the microfluidic devices can be exchanged easily when different sensors chips are used in order to adjust for the active sensor surface area. The flexible microfluidic device is positioned over the active sensor cell and a spring-loaded mechanical force is applied to assure a proper sealing. The biosensor system [1] is equipped with fluidic handling, high frequency electronics and data acquisition for bio-analytical measurements. 5-channel surface acoustic wave (SAW) sensor arrays with a limitof-detection of 800 femtogramm/mm² [2] and high frequency nanogap impedance sensors [3,4] are used for bio-analytical real-time measurements such as protein-antibody binding. For the measurement of the reaction kinetics, fluidic exchange times of about 1-3 sec. have to be realized. Therefore, the total volumes of the fluidic cells should be about 2 microliter/channel for the SAW sensor and 0.2 microliter/channel for the impedance sensor. In addition to all requirements for Lab-on-a-chip applications, a low price of the material and the possibility for an easy exchange of these devices should enable their use as fluidic disposables. Furthermore, the fluidic design should allow in-situ immobilization of at least two different types of receptor molecules on the same sensor chip.
J11.4.2
EXPERIMENTAL Materials The materials used for the fabrication of fluidic device
Data Loading...
