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Letters to the editor are presented in response to several articles in previous issues such as one on the search for autographed photos of golden age stars by Rod Labbe in the April 2015 issue, one on Bobby Driscoll in the June 2015 issue, and one on actor James Best by Joe Collura in the July 2015 issue.

We present a simple “top-down/bottom-up” strategy to fabricate nano- and micropatterned polymer brush arrays composed of pH- and salt-sensitive, weak polyelectrolyte copolymers poly(N-isopropylacrylamide-co-methacrylic acid, 3:1, poly(NIPAAM-co-MAA). In our approach, a silicon surface is first patterned with gold, using “lift-off” electron-beam lithography (“top-down”), and the resulting pattern is then amplified by surface-initiated photopolymerization by conventional, UV-light-induced free radical polymerization (“bottom-up”) from an immobilized 2,2‘-azobisisobutyronitrile (AIBN) type initiator. The use of pH- and ionic-strength-sensitive comonomers in the copolymer brush enables large, externally triggered conformational changes of the micro- and nanopatterned polymer brushes. We observed that the height of nanopatterned ionized polymer brushes increases with increasing feature size of the pattern. The design and fabrication of surfaces with conformationally switchable, patterned polymeric structures is important for sensing and actuation applications on the micro- and nanoscales.