Figure 14.

(a) The basic structure of pNIPAm-co-N-(3-aminopropyl) methacrylamide hydrochloride microgel-based etalon; (b) A schematic representation of a single reflectance peak. Here, the microgels are positively charged in water with pH < 10.0; (c) After addition of ssDNA, the microgels were crosslinked and collapsed, reducing the distance between the two Au layers of the device; (d) The peak of the reflectance spectrum shifts to a shorter wavelength. Reprinted with the permission of [57] Copyright ^© 2014, Springer Verlag Berlin Heidelberg.