Whole-Cell Biosensor with Tunable Limit of Detection Enables Low-Cost Agglutination Assays for Medical Diagnostic Applications

• DOI: 10.1021/acssensors.8b01163
• Publication Date: 2019-01-09T12:42:14Z
• Authors: Nicolas Kylilis; Pinpunya Riangrun...; Hung-En Lai; Valencio Salema; Luis Ángel Fernández; Guy-Bart V. Stan; Paul S. Freemont; Karen M. Polizzi
• Keywords: Point-of-Care Testing; Point of care

Whole-cell biosensors can form the basis of affordable, easy-to-use diagnostic tests that be readily deployed for point-of-care (POC) testing, but to date detection analytes such as proteins cannot easily diffuse across cell membrane has been challenging. Here we developed a novel biosensing platform based on agglutination using an E. coli whole-cell biosensor surface-displaying nanobodies which bind selectively target protein analyte. As proof-of-concept, show feasibility this design detect model analyte at nanomolar concentrations. Moreover, architecture is flexible by building assays optimized range concentrations straightforward rules and mathematical model. Finally, re-engineer our medically relevant biomarker display two different against human fibrinogen demonstrate limit low 10 pM in diluted plasma. Overall, technology fulfills requirement POC testing combining low-cost nanobody production, customizable limits. This potential produce affordable diagnostics field-testing developing world, emergency or disaster relief sites, well routine medical personalized medicine.