Fig. 2: Adhesion mechanism of nanohesives.
From: Designing nanohesives for rapid, universal, and robust hydrogel adhesion
a SEM analysis of adhesive interface in nanohesion. b Clear morphological distinction is shown at adhesive interface. Magnified images in (c) reveal that layers of ANP bridge the surfaces. SEM observation was repeated three times independently, yielding similar results. d Two states of ANP interlinking, the bridging state and Pickering state, are presented at the interface. e The interactions between ANP and surfaces were the collective short-range forces. f Evaluation of adhesion between nanohesives and substrates with varied nanoparticles-hydrogel interactions. D hydrogel represents dissipative hydrogel, PAA represents polyacrylic acid, and PAM represents polyacrylamide. g Comparison of nanohesion (bonding hydrogel to pristine glass) versus chemical anchoring (between hydrogel network and vinyl modified glass surface) and cyanoacrylates (bonding hydrogel to PC plate). h Adhesion energy of nanohesives with different ANP sizes. i Adhesion energy of nanohesives with two different ANP sizes, to hydrogels with varying crosslinking degree. j Adhesion energy and matrix toughness vary with the energy dissipative agarose content in hydrogel. Values in f–j represent mean ± standard deviation (s.d.) (n = 3 independent samples).
