In this work, designs for planar, interdigitated circular electrode structures for cell membrane permeabilization procedures are analysed using finite element method analysis. The generated electric field intensity, homogeneity, and the Joule heating are evaluated. The optimal electrode configuration for successful transfection procedures is investigated. Based on the simulation results, an optimized design for the electrodes, suitable for the investigation of the permeabilization thresholds during electroporation is proposed. The Joule heating influence simulation results are validated experimentally.

No abstract

This paper is focused on the feasibility study of parylene as a biocompatible coating for planar electroporation microelectrodes. The planar parallel and the circular interdigitated electrodes are applied in the analysis. The electrodes feature 100 μm width with a 300 μm gap between anode and cathode. The parylene coating thickness was varied in the 250 nm-2 μm range. The resultant electric field distribution evaluation has been performed using the finite element method. The electrodes have been applied in electroporation experiments with Saprolegnia parasitica. For reference the additional experiments using conventional electroporation cuvette (1 mm gap) have been performed. It has been determined that the parylene coating with hydrophobic properties has limited applicability for the passivation of the planar electroporation electrodes.

Integration of sensors and silicon-based electronics for harsh environment applications is driven by the automotive industry and the maturity of semiconductor processes that allow embedding sensitive elements onto the same chip without sacrificing the performance and integrity of the electronics. Sensor devices postprocessed on top of electronics by surface micromachining allow the addition of extra functionality to the fabricated ICs and creating a sensor system without significant compromise of performance. Smart sensors comprised of sensing structures integrated with silicon carbide-based electronics are receiving attention from more industries, such as aerospace, defense and energy, due to their ability to operate in very demanding conditions. This thesis describes the design and implementation of a novel, integrated thin film temperature sensor that uses a half-bridge arrangement to measure thin film platinum sensitive elements. Processes have been developed to fabricate temperature insensitive thin film tantalum nitride resistors which can be combined with the platinum elements to form the temperature transducing bridge. This circuit was designed to be integrated with an existing silicon carbide-based instrumentation amplifier by post-CMOS processing and to be initially connected to the bond pads of the amplifier input and output ports. Thin films fabricated using the developed TaN and Pt processes have been characterized using resistive test structures and crystallographic measurements of blanket thin film layer samples, and the relationship between the measurement results obtained has been analyzed. An initial demonstration of temperature sensing was performed using tantalum nitride and platinum thin film resistor element chips which were fabricated on passivated silicon substrates and bonded into high temperature packages. The bridge circuit was implemented by external connections through a printed circuit board and the bridge output was connected to a discrete instrumentation amplifier to mimic the integrated amplifier. The temperature response of the circuit measured at the output