title: Improved DET communication between cellobiose dehydrogenase and a gold electrode modified with a rigid self-assembled monolayer and green metal nanoparticles: The role of an ordered nanostructuration.
abstract: Efficient direct electron transfer (DET) between cellobiose dehydrogenase from Corynascus thermophilus (CtCDH) and a novel gold electrode platform, obtained by covalent linking of green AuNPs and AgNPs modified with a dithiol self-assembled monolayer, consisting of biphenyl-4,4'-dithiol (BPDT), was presented. The green AuNPs and AgNPs were synthesized using quercetin as reducing agent at room temperature. TEM experiments showed that the AuNPs and AgNPs were circular in shape with an average diameter of 5 and 8nm, respectively. Cyclic voltammetry of CtCDH immobilized onto the AuNPs/BPDT/AuE and the AgNPs/BPDT/AuE electrode platforms were carried out and compared with naked AuE, BPDT/AuE, AuNPs/AuE, and AgNPs/AuE. A pair of well-defined redox waves in neutral pH solution due to efficient DET of CtCDH was present with both MNPs/BPDT/AuE platforms. No DET communication was found with platforms without MNPs linked to BPDT. The apparent heterogeneous electron transfer rate constants (kS) of CtCDH were calculated to be 21.5±0.8s-1and 10.3±0.7s-1, for the AuNPs/BPDT/AuE and the AgNPs/BPDT/AuE platforms, respectively. The modified electrodes were successively used to develop an eco-friendly biosensor for lactose detection. The CtCDH/AuNPs/BPDT/AuE based biosensor showed the best analytical performances with an excellent stability, a detection limit of 3µM, a linear range between 5 and 400µM and a sensitivity of 27.5±2.5µAcm-2mM-1. Such performances were favorably compared with other lactose biosensors reported in literature. The biosensor was successively tested to quantify lactose content in real milk and cream samples. No significant interference present in the sample matrices was observed.
authors.affiliation: Department of Chemistry and Drug Technologies, Sapienza University of Rome, P.le Aldo Moro 5, 00185 Rome, Italy.
authors.forename: P
authors.initials: P
authors.lastname: Bollella
authors.affiliation: Department of Chemistry and Drug Technologies, Sapienza University of Rome, P.le Aldo Moro 5, 00185 Rome, Italy.
authors.forename: F
authors.initials: F
authors.lastname: Mazzei
authors.affiliation: Department of Chemistry and Drug Technologies, Sapienza University of Rome, P.le Aldo Moro 5, 00185 Rome, Italy.
authors.forename: G
authors.initials: G
authors.lastname: Favero
authors.affiliation: Department of Chemistry and Drug Technologies, Sapienza University of Rome, P.le Aldo Moro 5, 00185 Rome, Italy.
authors.forename: G
authors.initials: G
authors.lastname: Fusco
authors.affiliation: Food Biotechnology Laboratory, Department of Food Science and Technology, BOKU - University of Natural Resources and Life Sciences, Muthgasse 18, A-1190 Vienna, Austria.
authors.forename: R
authors.initials: R
authors.lastname: Ludwig
authors.affiliation: Department of Analytical Chemistry/Biochemistry and Structural Biology, Lund University, P.O.Box 124, SE-221 00 Lund, Sweden.
authors.forename: L
authors.initials: L
authors.lastname: Gorton
authors.affiliation: Department of Chemistry and Drug Technologies, Sapienza University of Rome, P.le Aldo Moro 5, 00185 Rome, Italy. Electronic address: riccarda.antiochia@uniroma1.it.
authors.forename: R
authors.initials: R
authors.lastname: Antiochia
mesh_terms: D000818:Animals; D015374:Biosensing Techniques / Q000379:methods*; D002237:Carbohydrate Dehydrogenases / Q000737:chemistry*; D004566:Electrodes; D004579:Electron Transport; D004800:Enzymes, Immobilized / Q000737:chemistry; D005504:Food Analysis / Q000379:methods; D006046:Gold / Q000737:chemistry*; D055772:Green Chemistry Technology / Q000379:methods; D007785:Lactose / Q000032:analysis*; D057230:Limit of Detection; D053768:Metal Nanoparticles / Q000737:chemistry* / Q000648:ultrastructure; D008892:Milk / Q000737:chemistry*; D008958:Models, Molecular; D012834:Silver / Q000737:chemistry*; D020037:Sordariales / Q000201:enzymology*
chemical_list: D004800:Enzymes, Immobilized; D012834:Silver; D006046:Gold; D002237:Carbohydrate Dehydrogenases; C019859:cellobiose-quinone oxidoreductase; D007785:Lactose
keywords: Biphenyl-4,4′-dithiol; Cellobiose dehydrogenase; Direct electron transfer; Gold nanoparticles; Lactose; Silver nanoparticles