Scanning the strength of a test signal to monitor electrode degradation within bio-fluidic microsystems

Lab-on-Chip devices are complex multifunctional heterogeneous microsystems that have the potential to strongly influence advances in important areas such as pharmacology, security, and environmental analysis. High reliability requirements in many of these microsystems are crucial which makes test more challenging especially given the need to validate multiple multi-domain interfaces and realise on-line solutions. Based on fault modeling and impedance analysis of the electrode/electrolyte interface and a customised prototype array structure, this paper proposes a self-test solution that targets degraded sensing microelectrodes within Multi Electrode Array´s (MEA). The principle of this approach is to scan the strength of a test signal over the whole array to monitor the defective sensing electrodes. The test solution has been applied at the system level where an analogue multiplexer, an LCD, and a microcontroller have been used to achieve a real time condition monitoring technique.