Figure 17.

Illustration of different approaches that have been used to modify the surface-chemistry of high-aspect-ratio nanostructures. Note: surface chemistry mechanisms are often complex and multiple bindings may coexist on the same surface, for example only one mechanism is shown for silane binding in C, but more are possible.^[285] Similarly the mechanism of the sulfur-gold bond in D has been of considerable discussion in the literature.^[286,287] In F, the blue and bold portions of the line represent the presence of an integrin-recognized peptide-binding sequence within the overall peptide.