TY - JOUR A1 - Dollendorf, Christian A1 - Hetzer, Martin A1 - Ritter, Helmut T1 - Polymeric redox-responsive delivery systems bearing ammonium salts cross-linked via disulfides JF - Beilstein Journal of Organic Chemistry PY - 2013/// VL - 9 SP - 1652 EP - 1662 SN - 1860-5397 DO - 10.3762/bjoc.9.189 PB - Beilstein-Institut JA - Beilstein J. Org. Chem. UR - https://doi.org/10.3762/bjoc.9.189 KW - cationic hydrogel KW - cross-linked polymer KW - 2-(dimethylamino)ethyl methacrylate (DMAEMA) KW - disulfide cleavage KW - N,N-diethylacrylamide (DEAAm) N2 - A redox-responsive polycationic system was synthesized via copolymerization of N,N-diethylacrylamide (DEAAm) and 2-(dimethylamino)ethyl methacrylate (DMAEMA). N,N’-bis(4-chlorobutanoyl)cystamine was used as disulfide-containing cross-linker to form networks by the quaternization of tertiary amine groups. The insoluble cationic hydrogels become soluble by reduction of disulfide to mercaptanes by use of dithiothreitol (DTT), tris(2-carboxyethyl)phosphine (TCEP) or cysteamine, respectively. The soluble polymeric system can be cross-linked again by using oxygen or hydrogen peroxide under basic conditions. The redox-responsive polymer networks can be used for molecular inclusion and controlled release. As an example, phenolphthalein, methylene blue and reactive orange 16 were included into the network. After treatment with DTT a release of the dye could be recognized. Physical properties of the cross-linked materials, e.g., glass transition temperature (Tg), swelling behavior and cloud points (Tc) were investigated. Redox-responsive behavior was further analyzed by rheological measurements. ER -