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ad ls t par at ene dul e to up llin ne a nucleic r base er wit n bon ubjecte o stran single e to t prepared water-insoluble and nuclease-resistant DNA films by UV radiation [5], while Yamamoto and co-workers prepared DNA liquid crystal gels by the reaction with metal cations [6,7]. DNA/ nanoparticle hybrids [8], DNA-immobilized nonwoven cellulose fabric [9], DNA complexes with lipids [10], cationic surfactants [11,12], DNA immobilized in gels [13,14], semi-interpenetrating networks [15], DNA films [16], and hydrogels containing DNA strands as grafts [17], or as crosslinks [18] are among materials epoxide groups on both ends that can react with the amino groups on the nucleotide bases to form a three dimensional DNA network [23]. DNA hydrogels are responsive systems exhibiting drastic vol-ume changes in response to the external stimuli, such as the com-position of aqueous solutions of acetone [22,24], or polyethylene glycol [25], concentrations of inorganic salts [26–29], polyamines [27,28], cationic macromolecules [30], or surfactants [27,28,31]. We have recently focused on developing responsive DNA hydrogels with a wide range of tunable properties such as the conformation of the network strands [25], viscoelasticity [32], and nonlinear elasticity (strain hardening) [33]. Gelation reactions conducted a