This research involves design and building of a three-dimensional (3D) microarray device, with position-controlled microspheres, to perform simultaneous, efficient, and accurate screening of complementary DNAs, RNAs, and protein receptors on a single platform. This new device is portable, self-contained, automatic, and cost effective. Applications of this device include medical screening, drug discovery, and gene sequencing. In particular, it performs inexpensive disease diagnosis and provide insight into the molecular basis in different patients.
In existing 3D microarrays, microspheres are placed randomly within a substrate. This random placement of the microspheres makes their packing inefficient and their data processing complex. To overcome these drawbacks, the investigators design and build new microarrays with position-controlled microspheres. They analyze the statistical accuracy in estimating the target concentrations by computing performance bounds, and apply the results to select the minimal distance between the microspheres and the best operating temperature, while ensuring desired optimal estimation accuracy. The minimal microsphere distance enables high packing, and the optimal temperature reduces the cost. The investigators implement the position-controlled microarray using a microfluidic approach; particularly, they emplace the microspheres using a hydrodynamic trapping mechanism and using on-chip microvalves and pumps. The long-term goal is to integrate this device with image sensors, electronics, and optofluidic imaging to build a complete lab-on-a-chip system.
