Figure 2.
SEM images of a 2D array of polystyrene nanoparticles with mannose-hydrogel-filled interstices showing (a) a close-packed array when the hydrogel is collapsed and (b) a non-close-packed array when the hydrogel is swollen. (c) Dependence of the normalized diffraction spectra of 2D mannose hydrogel sensors on the concanavalin A concentration. The inset photographs demonstrate the sensor’s color change with increasing concanavalin A concentration. Reprinted from ref 20. Copyright 2014 American Chemical Society.