Toward a Simplified Microfluidic Device for Ultra-Fast Genetic Analysis with Sample-In/Answer-Out Capability: Application to T-Cell Lymphoma Diagnosis

Abstract
If microfluidic devices capable of rapid genetic analysis are to affect clinical diagnostics, they ultimately must be capable of carrying out more than ultra-rapid electrophoretic separations. The last half decade has seen a groundswell of activity in defining miniaturized DNA sample preparation methodologies that can be integrated with chip-based electrophoretic separations. Successfull integration of PCR-based DNA amplification and solid-phase DNA sets the stage for integrated microminiaturized analytical systems with sample in-answer out capabilities. Here we provide a brief review of the state of the art on the microfluidic integration of sample preparation processes with discussion of several systems with highly integrated capabilities, including one capable of detection of infectious agents present in complex biofluids in less than 30 min. This overview is used as a launch point to discuss the design and functionality of similar devices capable of accepting a whole blood or fine-needle aspirate sample, purifying the DNA, amplifying target sequences of the T-cell receptor-γ gene, and eletrophoretically resolving the products for detection of a signature consistent with monoclonality. We describe the details of the early experimental success in defining the individual chip-based processes required for an integrated T-cell lymphoma chip, with a vision to a device that provide sample in-answer out capabilities for diagnosing certain blood cancers in roughly 1 h.