Bracher, Paul J.Gupta, MalanchaWhitesides, George2018-12-142009-01-26Bracher, Paul J., Malancha Gupta, and George M. Whitesides. 2009. “Shaped Films of Ionotropic Hydrogels Fabricated Using Templates of Patterned Paper.” Advanced Materials 21 (4): 445–50. https://doi.org/10.1002/adma.200801186.0935-96481521-4095http://nrs.harvard.edu/urn-3:HUL.InstRepos:37907089Patterned paper wet with multivalent cations can template the production of films of ionotropic hydrogels in topologically complex shapes such as Mobius strips and interlocking rings (see figure). The films have lateral dimensions as low as 2mm, and range in thickness from 0.2 to 1.3mm. The films are magnetically responsive when cross-linked by Ho(3+) or Gd(3+).en-USJournal Article2018-12-1410.1002/adma.200801186