Abstract

Microfluidic chips facilitate the manipulation of nanoliter fluid volumes in order to perform chemical analysis or synthesis and biological cell manipulation. On-chip valves are employed when complex flow control schemes are desired. Stimuli-sensitive hydrogels can be used to create transistor-like microfluidic valves whose opening or closing behavior is determined by the content of chemicals in the liquid. Here, we present a design and simulation method that simplifies the development of hydrogel-based micro-fluidic chips by reducing the amount of experiments that need to be performed in the lab. Cadence Virtuoso, a tool commonly used for electronic circuit design, is employed as a framework for the implementation of the method. Like in electronics, the microfluidic circuit consists of basic components (channels, valves, pumps) that can be placed and connected with each other in the schematic design interface. The physical-mathematical behavior of these components is implemented in VerilogAMS, a hardware description language. The method was successfully employed in the top-down design of a chemofluidic oscillator. In addition, parts of the design process of the photomasks for chip fabrication were automated by the use of parameterized cells and the SKILL programming language.