Discrimination of Escherichia coli strains using Glycan Cantilever Array Sensors
Andreas Mader, Kathrin Grubert, Ricardo Castelli, Bianca A. Hermann, Peter H. Seeberger, Joachim O. Rädler, Madeleine Leisner
Advances in carbohydrate sequencing technologies have revealed the tremendous complexity of the glycome. Understanding the biological function of carbohydrates requires the identification and quantification of carbohydrate interactions with biomolecules. The increasing importance of carbohydrate-based sensors able to specifically detect sugar binding molecules or cells, has been shown for medical diagnostics and drug screening. Our biosensor with a self-assembled manno- side based sensing layer that specifically detects carbohydrate-protein binding interactions (mannoside - ConA), as well as real time interac- tion of carbohydrates with different E. coli strains in solution. Bind- ing to the Cantilever surface causes mechanical surface stress, that is transduced into a mechanical force and cantilever bending. The degree and duration of cantilever deflection correlates with the interaction's strength. In this study we present carbohydrate-based cantilever biosensors as a robust, label-free, and scalable method to analyze carbohydrate-protein and carbohydrate-bacteria interactions. The cantilevers thereby exhibit specific and reproducible deflection with a high sensitivity range of over four orders of magnitude.