Supporting Information. Materials, instruments, and methods showing the production, characterization and labeling of the three lectins (DC-SIGN, DC-SIGN-C and DC-SIGNR); preparation and characterization of QD-DiMan hydrodynamic size and surface glycan valency; characterization of QD-DiMan lectin hydrodynamic sizes, and the kinetic fitting equations. "This material is available free of charge via the Internet at ."