The same interactions that a pathogen uses for establishment in a host can be exploited in its detection. The carbohydrates comprising the intestinal cell surface GM1-ganglioside, are targeted by vibrio cholerae via the lectin, cholera toxin, to initiate infection. We report on the preparation of mixed-monolayer, carbohydrate-coated silver nanoparticles (glyconanoparticles) for the sensitive (56 ng/mL), low volume detection of cholera toxin B-subunit (CTB) in synthetic freshwater samples and in 5 minutes by surface enhanced Raman spectroscopy (SERS). The detection limit falls within the recommended detection range and matches WHO approved test limits. PEGylated galactose and sialic acid are added in a specific ratio to coat the particles in GM1-ganglioside mimics for interaction with CTB and display a synergic effect greater than either glycan alone. This demonstrates the first use of a mixed-monolayer glyconanoparticle which mimics the GM1 ligand, allowing selective interaction with CTB.
- cholera toxin B-subunit
- mixed-monolayer glyconanoparticle
Simpson, J., Craig, D., Faulds, K., & Graham, D. (2016). Mixed-monolayer glyconanoparticles for the detection of cholera toxin by surface enhanced raman spectroscopy. Nanoscale Horizons, (1), 60-63. https://doi.org/10.1039/C5NH00036J