Efficient parallel testing and diagnosis of digital microfluidic biochips

Abstract

Microfluidics-based biochips consist of microfluidic arrays on rigid substrates through which movement of fluids is tightly controlled to facilitate biological reactions. Biochips are soon expected to revolutionize biosensing, clinical diagnostics, environmental monitoring, and drug discovery. Critical to the deployment of the biochips in such diverse areas is the dependability of these systems. Thus robust testing and diagnosis techniques are required to ensure adequate level of system dependability. Due to the underlying mixed technology and mixed energy domains, such biochips exhibit unique failure mechanisms and defects. In this article efficient parallel testing and diagnosis algorithms are presented that can detect and locate single as well as multiple faults in a microfluidic array without flooding the array, a problem that has hampered realistic implementation of several existing strategies. The fault diagnosis algorithms are well suited for built-in self-test that could drastically reduce the operating cost of microfluidic biochip. Also, the proposed alogirthms can be used both for testing and fault diagnosis during field operation as well as increasing yield during the manufacturing phase of the biochip. Furthermore, these algorithms can be applied to both online and offline testing and diagnosis. Analytical results suggest that these strategies that can be used to design highly dependable biochip systems.

Algorithmic Challenges in Digital Microfluidic Biochips: Protocols, Design, and Test

“…Several test procedures to detect such defects and malfunctions appear in [54][55][56]. On-line testing and error detection methods, which are suitable for in-field operation have been reported in the literature [10,[57][58][59].…”

Testing of Low-cost Digital Microfluidic Biochips with Non-Regular Array Layouts

“…These fluidic devices are connected using electrode paths for droplet routing, and other regions are left unused without any electrode. Previous testing methods target the detection of manufacturing defects in a 2-D regular microfluidic array [6,7,17,21,23,24,27]. In [6], efficient parallel testing and diagnosis algorithms are proposed to detect and locate single as well as multiple faults in a regular microfluidic array.…”

“…Previous testing methods target the detection of manufacturing defects in a 2-D regular microfluidic array [6,7,17,21,23,24,27]. In [6], efficient parallel testing and diagnosis algorithms are proposed to detect and locate single as well as multiple faults in a regular microfluidic array. In [23], the test planning problem for detecting the single-electrode catastrophic defect is formulated in terms of graph partitioning and the Hamiltonian path problem from graph theory.…”

“…Several testing methods have been proposed to detect defects in microfluidic biochips and twodimensional (2-D) regular microfluidic arrays [6,7,11,17,18,21,23,24,27]. In [21], faults were classified as being either catastrophic or parametric, and detected by electrically controlling and tracking the motion of test droplets.…”

An on-line monitoring technique for electrode degradation in bio-fluidic microsystems

“…These methods utilize digital microfluidic (exclusive-OR/AND) gates to implement an output comparator. An efficient testing and diagnosis methodology for digital microfluidic biochips has also been proposed in [19]. This method is based on a partitioning technique that increases parallelism in testing and diagnosis by exploiting the available sources and sinks which supports the ability to detect and locate single as well as multiple faults in a microfluidic array.…”