title: Immobilized horseradish peroxidase on discs of polyvinyl alcohol-glutaraldehyde coated with polyaniline.
abstract: Discs of network polyvinyl alcohol-glutaraldehyde (PVAG) were synthesized and coated with polyaniline (PANI) using glutaraldehyde as a chemical arm (PVAG-PANIG-HRP disc). The best conditions for the immobilization were established as about 1.0 mg mL(-1) of protein, for 60 min and pH 5.5. The soluble enzyme lost all of its activity after incubation at 70°C for 15 min, whereas the PVAG-PANIG-HRP disc retained about half of the initial activity for pyrogallol. The same PVAG-PANIG-HRP disc was used consecutively three times without any activity lossbut presented 25% of the initial activity after the 7th use. PVAG-PANIG-HRP disc retained approximately 80% and 60% of its initial activity after 60 and 80 days of storage, respectively. Resorcinol, m-cresol, catechol, pyrogallol, α-naphthol, βnaphthol, and 4, 4'-diaminodiphenyl benzidine were efficiently oxidized by the PVAG-PANIG-HRP disc (from about 70% to 90%), and it was less efficient towards aniline, phenol, and 2-nitrosonaphthol.
authors.affiliation: Unidade Universitária de Ciências Exatas e Tecnológicas, Universidade Estadual de Goiás, Caixa Postal 459, Rodovia BR 153, Km 9875132-903 Anápolis, GO, Brazil. samantha.salomao@ueg.br
authors.forename: Samantha Salomão
authors.initials: SS
authors.lastname: Caramori
authors.forename: Kátia Flávia
authors.initials: KF
authors.lastname: Fernandes
authors.forename: Luiz Bezerra
authors.initials: LB
authors.lastname: de Carvalho Junior
mesh_terms: D000814:Aniline Compounds / Q000737:chemistry*; D004800:Enzymes, Immobilized / Q000737:chemistry*; D005976:Glutaral / Q000737:chemistry*; D006735:Horseradish Peroxidase / Q000737:chemistry*; D011142:Polyvinyl Alcohol / Q000737:chemistry*
chemical_list: D000814:Aniline Compounds; D004800:Enzymes, Immobilized; C416807:polyaniline; D011142:Polyvinyl Alcohol; D006735:Horseradish Peroxidase; D005976:Glutaral