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Series of polyelectrolyte−surfactant complexes, DNA−cationic surfactant complexes (cetyltrimethylammonium, cetylpyridinium, and cetylbenzyldimethylammonium), and their self-assembled bulk film materials were prepared on a large scale. Circular dichroism (CD) analysis indicated that the right-handed double helix structure of DNA was retained in these bulk film materials. TGA analysis suggested that 4 molecules of water were required to retain the B-type conformation of the DNA helix in the self-assembled bulk film materials. In addition, it revealed that DNA and the DNA−surfactant complex film materials were thermostable up to as high as 180 °C. Thermodynamical analysis indicated that these film materials were thermo-extensive over a temperature range from 100 to 148 °C. The DNA conformation in the supramolecular complex films can be reversibly tuned by changing the environmental humidity. Film formation was found to occur by self-assembly and self-organization with evaporation of solvent molecules. Various functional dyes such as laser dye, NLO dye, and photochromic dye could easily be incorporated in the self-assembled supramolecular complex films as adducts. Studies of the induced CD spectra demonstrated that 4[4-(dimethylamino)styryl]-1-dococylpyridinium (DMASDPB) could orient on the chiral nanotemplates of DNA in the self-assembled films. UV−vis analysis indicated that these film materials have high transparency from 300 to about 1000 nm. These self-assembled functional-dye-containing DNA−surfactant complex materials, with good processability for multilayer integration into large-area devices, will have promising applications in molecular optical and molecular optoelectronic fields.

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Complex formation between PDMAAm as a hydrogen-bonding acceptor and PAAc as a hydrogenbonding donor, the temperature dependence of the equilibrium swelling for interpenetrating polymer network (IPN) hydrogels composed of PDMAAm and PAAc, and changes in ketoprofen release of these IPN hydrogels were investigated. Interpolymer complexes between PDMAAm and PAAc were very stable at 70 °C in aqueous solution. Dissociation temperatures of the complex between poly(DMAAm-co-AAm) and PAAc shifted to higher values with increasing DMAAm content. These IPNs composed of poly(DMAAm-co-AAm) and PAAc showed limited swelling ratios between their swelling transition temperatures and lower swelling ratios above these transition temperatures. Transition temperatures shift to higher values with increasing DMAAm content. Reversible and pulsatile solute release, reflecting the "on" state at higher temperatures and the "off" state at lower temperatures, was achieved by fabricating these IPN hydrogels.

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