Synthetic biological systems for protein detection - Project Summary The goal of the proposed work is to create a new synthetic biology-based platform for protein diagnostics. The specific context motivating this challenge is the need to measure protein biomarkers indicative of micronutrient deficiencies in a minimal-equipment fashion. Current diagnostics for nutritional deficiencies are infeasible at the required population scale due to cost and logistical constraints, and so a point-of-care, minimal-equipment, field-deployable approach is needed to help nutritional epidemiologists get the information they need to better allocate limited intervention resources. However, the impact of such a technology would go well beyond nutritional epidemiology and diagnostics, as proteins are common biomarkers for many other diseases and conditions. Thus, the same technology could be translated to global health applications and screening for other diseases in resource-poor locations. In addition, it could also enable better diagnostic monitoring for neonatal intensive care unit patients by overcoming limitations on daily allowable blood draw volumes. The use of a split protein reporter system coupled with a cell-free protein expression system is proposed to accomplish this goal. In the presence of a specific protein, the split reporter system reassembles and the reaction undergoes a colorimetric change. The entire approach requires minimal to no equipment and would be inexpensive, making it perfectly suited for use in the low- resource regions that are most prominently affected by nutritional deficiencies. There is strong preliminary data supporting the likelihood of success for this approach. To achieve these goals, three aims are proposed. First, the existing proof of principle sensor will be advanced with a model protein target and the impact of sensor design choices on sensor functionality and performance will be characterized. The second aim entails demonstrating the approach’s generalizability by developing at least three sensors for clinically relevant proteins. The third aim involves advancing the assay towards a truly field-deployable state by testing it for functionality in a human serum matrix, implementing a calibration approach, demonstrating functionality after lyophilization, and developing a companion smartphone app to support output interpretation. This project will yield the underlying technology that can be used for the first-ever synthetic biology-based, quantitative protein detection assay for low-resource settings. By being low-cost, essentially point-of-care, and easily generalizable to other protein targets, such a long-term result would potentially improve the health of millions of people worldwide.