We have designed, fabricated, and tested a novel three-dimensional (3-D) flexible microprobe used for recording the neural signals of lateral giant (LG) on the escape system of American crayfish. We report an electrostatic actuation process to fold the planar probes to be the arbitrary orientations of 3-D probes for neuroscience application. The batch assembly method based on electrostatic force techniques gave more simple fabrication compared to others. A flexible probe could reduce both the chronic inflammation response and material fracture when animal breathes or moves. Furthermore, the cortex corresponds to hypothetical cortical modules with mostly vertically organized layers of neurons. Therefore, the 3-D flexible probe suits to understand how the cooperative activity for different layers of neurons. Advisedly, we present a novel fabrication for the 3-D flexible probe by using Parylene technology. The mechanical strength of the neural probe is strong enough to penetrate into a biogel. At the end, the flexible probe was used to record neural signals of the LG cell from American crayfish.
Polymerase chain reaction (PCR) is a molecular biological method for in vitro amplification of nucleic acids. Our objective was to design a micro-PCR system that included a Rayleigh-Bénard convection PCR chip, measurement circuits, and circuits to control the temperature. A Rayleigh-Bénard convection PCR chip was easily fabricated by using microelectromechanical system technology, and the sample solution could be put in to finish the completed PCR cycling within several minutes. The flow stream, velocity, and temperature profile in a micro-PCR system are important to achieve the successful PCR, but they are not easily observed with an experimental method. Thus, a CFDRC simulation of Rayleigh-Bénard convection PCR was undertaken to determine the above important parameters. The duration of one cycle, the extension time, and total duration of 25 cycles can be calculated to achieve the optimal design. Finally, using agarose-gel electrophoresis, we verified the practicability of this system. The comparison study of PCR experiments performed with a commercial PCR machine and our chips showed that our chips can greatly decrease the duration of the reaction. By comparing the simulation and PCR experiment results with varied designed sizes, a user can set the parameters and computational fluid dynamics results for optimal designs and decrease the total duration of future reactions.