Design-for-Testability for Digital Microfluidic Biochips

Testing is essential for digital microfluidic biochips that are used for safety-critical applications such as point-of-care health assessment, air-quality monitoring, and food-safety testing. However, the effectiveness of recently proposed test techniques for biochips is limited by the fact that current design methods do not consider testability. We introduce the concept of design-for-testability (DFT) for microfluidic biochips and propose a DFT method that incorporates a test plan into the fluidic operations of a target bioassay protocol. By using the testability-aware bioassay protocol as an input to the biochip design tool, the proposed DFT method ensures a high level of testability, defined as the percentage of the electrodes or functional units on the synthesized chip that can be effectively tested. We evaluate the DFT method using a representative multiplexed bioassay and the polymerase chain reaction.