Automating chemical assays via multi-layer tableting

Chemical sensors are essential for the detection of pathogens and contaminants in plants, food, humans, and animals. There have been significant developments in molecular tests for small molecules, proteins, nucleic acids, and carbohydrates in the last 20 years. However, most of the sensitive tests cannot be done by non-specialists and requires skilled technicians and equipment in a centralized laboratory facility. This issue is due to the fact that most tests have multiple steps and are complex to conduct. In this NSERC Discovery Grant, my aim is to develop a multi-step tablet (MST) capable of sequentially releasing reagents for each step of a detection procedure. To build these tablets, we have three aims: (1) develop methods to control the tablet's dissolution rate, (2) develop strategies to synthesize multi-step tablets (MSTs) with the ability to program the reaction time in each unit, and (3) optimize the MSTs for different molecular targets. The impact of this development is to enable the non-specialist to conduct complex and multi-step detection procedures. They can simply add a tablet, wait one hour, image the change in the signal using a smartphone camera, and use an app to interpret results. The user can send the results to a centralized facility for monitoring. Our main focus of this NSERC Discovery Grant is to develop methods to design these multi-step tablets (MSTs). The current NSERC Discovery Grant is significant to my research program. In 2003, our first NSERC Discovery Grant focused on developing detection technology with a long-term objective to translate these technologies for use by non-specialists. Through the last 19 years, we have developed nanoparticles (2004-2010), optimized and developed multiplex nanoparticle assays (2010-2015), and devices to readout the assays (2015-2020). We started to think of practical utility of our detection systems. This utility requires reagent portability, delivery and automation-this project is a crucial last cycle of our detection technology development. We published our studies in excellent journals to inspire others in this research area and patented many results. We have trained exceptional researchers that are having an impact in industry and academia. The next step after completing this project would be to advance our detection technology to commercial products for access by the broader community. Our partners will produce and manufacture our tablet, read-out instrument, and software for use by the general public. The completion of this fourth Discovery Grant would close the detection theme of my research laboratory. It will enable my group to explore other research topics (e.g., optoelectronics and displays).