Interactive Polymer Gels as Biomimetic Sensors for Carbohydrate Interactions and Capture-Release Devices for Pathogens

Adhesive processes mediated by carbohydrate-decorated interfaces play a crucial role in many biological processes such as cell development or pathogen invasion. The involved carbohydrate scaffolds are soft and present multiple subsites forming complex and dynamic bonds to carbohydrate binding proteins. New tools and data are needed to understand how ligand presentation and mechanical properties drive these binding processes. This article highlights recent developments in the area of adhesion assays with a focus on soft biomimetic carbohydrate scaffolds as probes of adhesion forces. Key findings state that carbohydrate functionalized polymer networks largely show additive multivalency (statistical effects) and that the overall interaction forces are strongly affected by the stiffness of the network. These results indicate that phase transitions of carbohydrate bearing polymer gels may enable tunable affinity toward carbohydrate binding proteins. As an example, polymer networks undergoing large changes in mechanical rigidity, density, and spacing of carbohydrate ligands upon temperature stimulus are shown to bind or release carbohydrate binding bacteria such as Escherichia coli. The presented adhesion assays and the developed responsive systems can provide new insights into the mechanism through which carbohydrates mediate adhesion processes and establish new avenues toward scaffolds for the capture or release of cells or pathogens.