Fully Integrated Molecular Diagnostic CD Platform Based on Thermal Control

Centrifugal microfluidics, or compact disc (CD) microfluidics, has been gaining popularity in the lab-on-a-chip field as an advanced diagnostic platform over the last fifteen years. The lab-on-a-disc (LoD) platform embodies advantages of the lab-on-a-chip platform, including small volumes, fast reaction times, low power consumption, and portability; it also has other unique advantages, including embedded fluid pump operation and ease of automation and multiplexing. These advantages make the lab-on-a-disc diagnostic system attractive due to its capability for rapid disease diagnosis. In clinical diagnostics, rapid nucleic acid biomarker detection generally has been a challenge especially due to the rigorous thermocycling required to bring the biomarker quantity up to a delectable level. This work follows the development of a diagnostic microfluidic disc that utilizes polymerase chain reaction for DNA amplification and a DNA microarray that allows for visual detection of numerous target biomarkers. The assay begins with a sample volume that undergoes preparation, thermocycling, post-processing, and detection, so a number of challenges must be addressed; these challenges include precise fluid manipulation, application of heat, and storage and release of reagents. Along the way, modular fluid-handling techniques, including the thermo-pneumatic pump (TPP) and the multifunctional wax valves (MWV), were implemented to reduce the complexity and cost of the overall hardware system. This system would not only be capable of nucleic acid amplification but also specialized multiplexed biomarker amplification and detection. It is anticipated that this platform will provide a foundation for the development of other fully-integrated LoD systems for rapid disease diagnosis in the near future