Whole-cell biosensor with tuneable limit of detection enables low-cost agglutination assays for medical diagnostic applications
File(s)
Published version
Supporting information
Author(s)
Type
Journal Article
Abstract
Whole-cell biosensors can form the basis of affordable, easy-to-use diagnostic tests that can be readily deployed for point-of-care (POC) testing, but to date, the detection of analytes such as proteins that cannot easily diffuse across the cell membrane has been challenging. Here we developed a novel biosensing platform based on cell agglutination using an E. coli whole-cell biosensor surface-displaying nanobodies which bind selectively to a target protein analyte. As a proof-of-concept, we show the feasibility of this design can detect a model analyte at nanomolar concentrations. Moreover, we show that the design architecture is flexible by building assays optimized to detect a range of model analyte concentrations using straight-forward design rules and a mathematical model. Finally, we re-engineer our whole-cell biosensor for the detection of a medically relevant biomarker by the display of two different nanbodies against human fibrinogen and demonstrate a detection limit as low as 10 pM in diluted human plasma. Overall, we demonstrate that our agglutination technology fulfills the requirement of POC testing by combining low-cost nanobody production, customizable detection range and low detection limits. This technology has the potential to produce affordable diagnostics for field-testing in the developing world, emergency or disaster relief sites as well as routine medical testing and personalized medicine.
Date Issued
2019-02-22
Date Acceptance
2019-01-09
Citation
ACS Sensors, 2019, 4 (2), pp.370-378
ISSN
2379-3694
Publisher
American Chemical Society
Start Page
370
End Page
378
Journal / Book Title
ACS Sensors
Volume
4
Issue
2
Copyright Statement
© 2019 American Chemical Society. This is an open access article published under a Creative Commons Attribution (CC-BY)License, which permits unrestricted use, distribution and reproduction in any medium,provided the author and source are cited.
Sponsor
Engineering & Physical Science Research Council (EPSRC)
Engineering & Physical Science Research Council (EPSRC)
Imperial College London
Engineering & Physical Science Research Council (EPSRC)
Identifier
https://www.ncbi.nlm.nih.gov/pubmed/30623662
Grant Number
EP/M002187/1
EP/K038648/1
Imperial College PhD Scholarship
EP/P009352/1
Subjects
Science & Technology
Physical Sciences
Chemistry, Multidisciplinary
Chemistry, Analytical
Nanoscience & Nanotechnology
Chemistry
Science & Technology - Other Topics
whole-cell biosensor
synthetic biology
point-of-care testing
medical diagnostics
latex agglutination test
immunoassay
ESCHERICHIA-COLI
ANTIBODY FRAGMENT
FIBRINOGEN
NANOBODIES
BINDING
PROTEIN
SURFACE
DESIGN
SELECTION
RECEPTOR
immunoassay
latex agglutination test
medical diagnostics
point-of-care testing
synthetic biology
whole-cell biosensor
Publication Status
Published
Coverage Spatial
United States
Date Publish Online
2019-01-09