title: Graphene oxide vs. reduced graphene oxide as carbon support in porphyrin peroxidase biomimetic nanomaterials.
abstract: The paper describes the preparation of supramolecular assemblies of tetrapyridylporphyrin (TPyP) and its metallic complexes with graphene oxide (GO) and thermally reduced graphene oxide (TRGO). The two carbon supports are introducing different characteristics in the absorption spectra of the investigated nanocomposites. Raman spectroscopy shows that the absorption of iron-tetrapyridylporphyrin is more efficient on GO than TRGO, suggesting that oxygen functionalities are involved in the non-covalent interaction between the iron-porphyrin and graphene. The biomimetic peroxidase activity is investigated and the two iron-containing composites exhibit a better catalytic activity than each component of the assembly, and their cobalt and manganese homologues, respectively. The main advantages of this work include the demonstration of graphene oxide as a very good support for graphene-based nanomaterials with peroxidase-like activity (K(M)=0.292 mM), the catalytic activity being observed even with very small amounts of porphyrins (the TPyP:graphene ratio=1:50). Its potential application in the detection of lipophilic antioxidants (vitamin E can be measured in the 10(-5)-10(-4) M range) is also shown.
authors.affiliation: National Institute for Research and Development of Isotopic and Molecular Technologies, 67-103 Donat, 400293 Cluj-Napoca, Romania. Electronic address: csocaci@itim-cj.ro.
authors.forename: C
authors.initials: C
authors.lastname: Socaci
authors.affiliation: National Institute for Research and Development of Isotopic and Molecular Technologies, 67-103 Donat, 400293 Cluj-Napoca, Romania.
authors.forename: F
authors.initials: F
authors.lastname: Pogacean
authors.affiliation: National Institute for Research and Development of Isotopic and Molecular Technologies, 67-103 Donat, 400293 Cluj-Napoca, Romania.
authors.forename: A R
authors.initials: AR
authors.lastname: Biris
authors.affiliation: National Institute for Research and Development of Isotopic and Molecular Technologies, 67-103 Donat, 400293 Cluj-Napoca, Romania.
authors.forename: M
authors.initials: M
authors.lastname: Coros
authors.affiliation: National Institute for Research and Development of Isotopic and Molecular Technologies, 67-103 Donat, 400293 Cluj-Napoca, Romania.
authors.forename: M C
authors.initials: MC
authors.lastname: Rosu
authors.affiliation: National Institute for Research and Development of Isotopic and Molecular Technologies, 67-103 Donat, 400293 Cluj-Napoca, Romania.
authors.forename: L
authors.initials: L
authors.lastname: Magerusan
authors.affiliation: Faculty of Chemistry and Chemical Engineering, Babes-Bolyai University, Arany Janos 11, Cluj-Napoca, Romania.
authors.forename: G
authors.initials: G
authors.lastname: Katona
authors.affiliation: National Institute for Research and Development of Isotopic and Molecular Technologies, 67-103 Donat, 400293 Cluj-Napoca, Romania. Electronic address: stela.pruneanu@itim-cj.ro.
authors.forename: S
authors.initials: S
authors.lastname: Pruneanu
mesh_terms: D032701:Biomimetics / Q000379:methods*; D002244:Carbon / Q000737:chemistry*; D006108:Graphite / Q000737:chemistry* / Q000378:metabolism; D049329:Nanostructures / Q000737:chemistry*; D010084:Oxidation-Reduction; D010087:Oxides / Q000737:chemistry* / Q000378:metabolism; D009195:Peroxidase / Q000737:chemistry; D011166:Porphyrins / Q000737:chemistry*; D013059:Spectrum Analysis, Raman / Q000379:methods
chemical_list: D010087:Oxides; D011166:Porphyrins; D002244:Carbon; D006108:Graphite; D009195:Peroxidase
keywords: Graphene oxide nanocomposites; Peroxidase-like activity; Supramolecular assemblies; Tetrapyridylporphyrin; Thermally reduced graphene oxide; Vitamin E