Concurrent Testing of Droplet-Based Microfluidic Systems for Multiplexed Biomedical Assays

We present a concurrent testing methodology for detecting catastrophic faults in droplet-based microfluidic systems and investigate the related problems of test planning and resource optimization. We apply this methodology to a droplet-based microfluidic array that was fabricated and used to perform multiplexed glucose and lactate assays. The test approach interleaves test application with the biomedical assays and prevents resource conflicts. We show that an integer linear programming model can be used to minimize testing time for a given hardware overhead due to droplet dispensing sources and capacitive sensing circuitry. The proposed approach is therefore directed at ensuring high reliability and availability of bio-MEMS and lab-on-a-chip systems, as they are increasingly deployed for safety-critical applications.