Janus Emulsions for the Detection of Bacteria

Janus emulsion assays that rely on carbohydrate-lectin binding for the detection of Escherichia coli bacteria are described. Surfactants containing mannose are self-assembled at the surface of Janus droplets to produce particles with lectin binding sites. Janus droplets orient in a vertical directio...

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Bibliographic Details
Main Authors: Kaplonek, Paulina, Seeberger, Peter H., Zhang, Qifan, Savagatrup, Suchol, Swager, Timothy M
Other Authors: Massachusetts Institute of Technology. Institute for Soldier Nanotechnologies
Format: Article
Published: American Chemical Society (ACS) 2018
Online Access:http://hdl.handle.net/1721.1/113582
https://orcid.org/0000-0001-8839-5091
Description
Summary:Janus emulsion assays that rely on carbohydrate-lectin binding for the detection of Escherichia coli bacteria are described. Surfactants containing mannose are self-assembled at the surface of Janus droplets to produce particles with lectin binding sites. Janus droplets orient in a vertical direction as a result of the difference in densities between the hydrocarbon and fluorocarbon solvents. Binding of lectin to mannose(s) causes agglutination and a tilted geometry. The distinct optical difference between naturally aligned and agglutinated Janus droplets produces signals that can be detected quantitatively. The Janus emulsion assay sensitively and selectively binds to E. coli at 10 4 cfu/mL and can be easily prepared with long-time stability. It provides the basis for the development of inexpensive portable devices for fast, on-site pathogen detection.