Expansion (length) as function of AMP concentration; polymer I, film size 5.0×2.0×0.4 mm, pH 7.0. Lower trace (○), in absence of buffer; upper trace (•), in presence of 0.02 M NaH2PO4 buffer. Schneider, H. J.; Liu, T. J.; Lomadze, N. Dimension changes in a chemomechanical polymer containing ethylenediamine and alkyl functions as selective recognition units. Eur. J. Org. Chem. 2006, 677-692. Copyright Wiley-VCH Verlag GmbH & Co. [39b].