New water-soluble and film-forming aminocellulose tosylates as enzyme support matrices with Cu2+-chelating properties

Within the framework of our studies on enzyme-compatible support matrix structures, we succeeded in making further derivatives of the new aminocellulose type 'P-CHZ-NH-(X)-NH2' (P = cellulose); (X) = -(CH2)(2)-(EDA),-(CH2)(2)-NH-(CH2)(2)-(DETA),-(CH2)(3)-NH-(CH2)(3)-(DPTA),-(CH2)(2)-NH-(CH2)(2)- NH-(CH2)2- (TETA) accessible by nucleophilic substitution reaction with ethylenediamine (EDA) and selected oligoamines starting from 6(2)-O-tosylcellulose tosylate (DStosylate = 0-8)- The C-13-NMR data show that the EDA and oligoamine residues are at C6 of the anhydroglucose unit (AGU) and that OH and tosylate are also (partially) present at C6. OH and partially tosylate are at C2/C3. All the synthesized aminocellulose tosylates were soluble in water and formed transparent films from their solutions. The aminocellulose tosylate solutions and the films prepared from them formed blue-coloured chelate complexes with Cu2+ ions, whose absorption maxima at wavelengths in the VIS region were located similarly to those of the CU2+ chelate complexes wit ! h EDA and with the oligoamines. AFM investigations have shown that the aminocellulose films, depending on structural and environment-induced factors influencing e.g. SiO2 polymer films, exhibit 'flat' topographies (< 1 nm), and on protonated NH2 polymer films, such as aminopropyl-functionalized polysiloxane films, 'nanostructured' topographies of derivative-dependent shape and nanostructure size as film supports in the form of 'nanotubes'. The aminocellulose films could be covalently coupled with glucose oxidase enzyme by various known and novel bifunctional reactions via NH2-reactive compounds. In this connection, it was confirmed again that the immobilized enzyme parameters, such as enzyme activity/area and Km value, can be changed by the interplay of aminocellulose film, coupling structure and enzyme protein in the sense of an application-relevant optimization.