Universiẗat, Diss., 2002--München.

At present, the global medical healthy strategy take the preventive medicine as a goal, and the most important thing of the preventive medicine prospect is personalized medical service, in which the medicine examination communication tool is the small and facile biochip platform. Lives the medicine tech industry is a strategic industry of industrial upgrading in our country, and the biochip industry is one of the important industries. The biochip industry is an emerging industry. In order to grasp this good opportunity and to avoid our country absenting in this stage, the biochip entrepreneurs need to adopt the superior strategy to satisfy the field. The focus of this research is the development process of biochip industry and industrial competitive advantage. We take Porter¡¦s raises ¡§The Competitive Advantage of Nations¡¨ diamond model as the research foundation to discuss Taiwan biochip industry. By the competitive advantage, the strategy localization and the competitive power analysis, we find out the relation between the biochip industries, the demand condition, the essential factor condition, the industrial structure and the enterprise manage. And further, we find out the influences of environment and government coordination on it. The conclusion of this research is that the biochip industry is a cross domain industry. It is possible to continue to manage forever only by the strategy alliance or the partner to seek for the market the tally company.

Techn. Universiẗat, Diss.--Dresden, 2005.

Universiẗat, Diss., 2003--Jena.

Trapping ability on a biochip device is useful for systematic cell addressing and real-time observation of single cells analysis, however, precise control over the cell movements remains challenging. This thesis addresses the problem of controlling movement of single cells on a biochip platform by a technique called the Dielectrophoretic (DEP) force. Existing researches showed that the DEP force offers precise control of cell movements through various microelectrode designs which generate strong polarization effects i.e., DEP forces, but with the expense of damaging cell’s structure. The thesis contribute three new microelectrode designs for trapping single cells: the dipole, the quadrupole and the adaptive octupole, structured on a metal-insulator-metal (multilayer) biochip platform called the Sandwiched Insulator with Back Contact (SIBC) biochip. Cores of the study lie on the microelectrode designs that are capable of generating strong DEP holding forces, the back contact to enhance trapping of single cells and the fabrication process of creating a metal-insulator-metal structure. This thesis also presents details on the experimental setups of the trapping experiments and the numerical analysis of the microelectrode designs. The SIBC biochip comprises of the back contact on the first metal layer, the microcavity (cell trap) on the insulator layer and the three microelectrodes on the second metal layer. Together, the three microelectrodes and the back contact generate DEP forces that attract particles/single cells toward microcavities and maintain their positioning in the traps. Prior to the fabrication, profiles of the DEP force generated by the microelectrodes are studied using COMSOL3.5a software. Simulation results suggest that the DEP trapping region can be created surrounding the microcavity if the microelectrode and the back contact are connected with AC signals that have different phases. The strongest DEP force can be obtained by setting the back contact and the microelectrodes with AC signals that have 180 degree phase difference. Evaluations on the trapping functionality for the three microelectrodes were conducted using polystyrene microbeads and Ishikawa cancer cells line suspended in various medium. Trapping capability of the three microelectrodes was demonstrated through experiments with 22 percent of the Ishikawa cancer cells and 17 percent of the polystyrene microbeads were successfully trapped. With these promising results, the new microelectrode designs together with the SIBC biochip structure have huge potentials for biomedical applications particularly in the field of diagnosis and identification of diseases.

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Universiẗat, Diss., 2003--Jena.

No description available.

Exocytosis is a fundamental cellular process where membrane-bound secretory granules from within the cell fuse with the plasma membrane to form fusion pore openings through which they expel their contents. This mechanism occurs constitutively in all eukaryotic cells and is responsible for the regulation of numerous bodily functions. Despite intensive study on exocytosis the fusion pore is poorly understood. In this research micro-fabrication techniques were integrated with biology to facilitate the study of fusion pores from cells in the anterior pituitary using the atomic force microscope (AFM). In one method cells were chemically fixed to reveal a diverse range of pore morphologies, which were characterised according to generic descriptions and compared to those in literature. The various pore topographies potentially illustrates different fusion mechanisms or artifacts caused from the impact of chemicals and solvents in distorting dynamic cellular events. Studies were performed to investigate changes in fusion pores in response to stimuli along with techniques designed to image membrane topography with nanometre resolution. To circumvent some deficiencies in traditional chemical fixation methodologies, a Bioimprint replication process was designed to create molecular imprints of cells using imprinting and soft moulding techniques with photo and thermal activated elastomers. Motivation for the transfer of cellular ultrastructure was to enable the non-destructive analysis of cells using the AFM while avoiding the need for chemical fixation. Cell replicas produced accurate images of membrane topology and contained certain fusion pore types similar to those in chemically fixed cells. However, replicas were often dehydrated and overall experiments testing stimuli responses were inconclusive. In a preliminary investigation, a soft replication moulding technique using a PDMS-elastomer was tested on human endometrial cancer cells with the aim of highlighting malignant mutations. Finally, a Biochip comprised of a series of interdigitated microelectrodes was used to position single-cells within an array of cavities using positive and negative dielectrophoresis (DEP). Selective sites either between or on the electrode were exposed as cavities designed to trap and incubate pituitary and cancer cells for analysis by atomic force microscopy (AFMy). Results achieved trapping of pituitary and cancer cells within cavities and demonstrated that positive DEP could be used as a force to effectively position living cells. AFM images of replicas created from cells trapped within cavities illustrated the advantage of integrating the Biochip with Bioimprint for cellular analysis.

Zugl.: Dresden, Techn. Univ., Diss., 2005