1335-57-5Relevant academic research and scientific papers
Copper Complexes as Bioinspired Models for Lytic Polysaccharide Monooxygenases
Concia, Alda Lisa,Beccia, Maria Rosa,Orio, Maylis,Ferre, Francine Terra,Scarpellini, Marciela,Biaso, Frédéric,Guigliarelli, Bruno,Réglier, Marius,Simaan, A. Jalila
, p. 1023 - 1026 (2017)
We report here two copper complexes as first functional models for lytic polysaccharide monooxygenases, mononuclear copper-containing enzymes involved in recalcitrant polysaccharide breakdown. These complexes feature structural and spectroscopic properties similar to those of the enzyme. In addition, they catalyze oxidative cleavage of the model substrate p-nitrophenyl-β-d-glucopyranoside. More importantly, a particularly stable copper(II) hydroperoxide intermediate is detected in the reaction conditions.
Cobalt sulfides/carbon nanohybrids: A novel biocatalyst for nonenzymatic glucose biofuel cells and biosensors
Li, Zihan,Li, Gangyong,Wu, Zhongdong,Jiao, Shuqiang,Hu, Zongqian
, p. 32898 - 32905 (2019)
Exploring high-performance electrocatalysts is of great importance in developing nonenzymatic biofuel cells. Hybrid nanostructures with transition metal compounds and carbon nanomaterials exhibit excellent electrocatalytic activity and have emerged as promising low-cost alternatives for various electrochemical reactions. Herein, we report cobalt sulfide/carbon nanohybrids via a facile synthesis, which have excellent electrocatalytic activity for glucose oxidation and oxygen reduction reaction. The nonenzymatic glucose biofuel cells equipped with cobalt sulfide/carbon nanohybrids deliver a high open circuit voltage of 0.72 V with a maximum open power density of 88 μW cm-2, indicating that cobalt sulfide/carbon nanohybrids are high performance biocatalysts for bioenergy conversion.
Three dimensional porous graphene-chitosan composites from ice-induced assembly for direct electron transfer and electrocatalysis of glucose oxidase
Qian, Lei,Lu, Lu
, p. 38273 - 38280 (2014)
Three dimensional porous graphene-chitosan (GR-CS) composites via ice-induced assembly for glucose oxidase (GOD) immobilization were reported for the first time. By adjusting the GR amount, the porous GR-CS composites containing different GR content could be produced. It was found that the GR amount played an important role in their morphologies. Higher GR amount resulted in more pores appearing in the GR-CS composites. When the GR amount was 70 wt%, the GR-CS composites (GR70-CS) had good flexibility and interpenetrating porous structures. The GR70-CS composite showed good stability, and still kept a porous structure even after dispersing and coating on the substrates. Current response from the GR70-CS composite modified glassy carbon electrode (GR70-CS/GCE) was about two times that from the bare GCE with Fe(CN) 63-/4- as a probe. The direct electrochemical behavior was observed when GOD was immobilized onto the GR70-CS/GCE. The GOD modified GCE also showed good electrocatalytic activity for glucose. Using ferrocenecarboxylic acid as a mediator, a linear relationship from 0.14 to 7.0 mM (R = 0.995) between currents and the glucose concentration with a detection limit of 17.5 μM was obtained. the Partner Organisations 2014.
Enzymatic Cascade Catalysis for the Synthesis of Multiblock and Ultrahigh-Molecular-Weight Polymers with Oxygen Tolerance
Liu, Zhifen,Lv, Yue,An, Zesheng
, p. 13852 - 13856 (2017)
Synthesis of well-defined multiblock and ultrahigh-molecular-weight (UHMW) polymers has been a perceived challenge for reversible-deactivation radical polymerization (RDRP). An even more formidable task is to synthesize these extreme polymers in the presence of oxygen. A novel methodology involving enzymatic cascade catalysis is developed for the unprecedented synthesis of multiblock polymers in open vessels with direct exposure to air and UHMW polymers in closed vessels without prior degassing. The success of this methodology relies on the extraordinary deoxygenation capability of pyranose oxidase (P2Ox) and the mild yet efficient radical generation by horseradish peroxidase (HRP). The facile and green synthesis of multiblock and UHMW polymers using biorenewable enzymes under environmentally benign and scalable conditions provides a new pathway for developing advanced polymer materials.
Redox Polymer Films Containing Enzymes. 2. Glucose Oxidase Containing Enzyme Electrodes
Gregg, Brian A.,Heller, Adam
, p. 5976 - 5980 (1991)
Glucose oxidase is covalently bound in a film of cross-linked, redox-conducting epoxy cement on the surface of electrodes.The binding simultaneously immobilizes the enzyme and connects it electrically with the electrode.The effects of cross-linker concentration, film thickness, enzyme concentration, temperature, and oxygen concentration on the steady-state electrocatalytic oxidation of glucose at the redox-epoxy enzyme electrodes are described.The catalytic "reaction layer" extends through the entire film, even for films as thick as ca. 5 μm.The limiting catalytic current density is a function of the enzyme concentration, reaching a maximum near 35 wtpercent enzyme for films about 1 μm thick.In such films, the activation energy for the electrocatalytic reaction at high glucose concentration is 63 kJ/mol, and the apparent Michaelis constant monotonically decreases with increasing enzyme concentration and increases with increasing oxygen concentration.These results are explained by postulating that in such ca. 1 μm thick redox-epoxy enzyme films that the rate-limiting kinetic step at high substrate concentration is related to electron transfer away from the enzyme active site, a process involving flexing of the cross-linked redox chain segments.This bottleneck may be attributed to the high activity of the enzyme and the small contact area between the redox polymer and the enzyme-active site that is recessed inside the insulating protein shell of the enzyme.
Nanoisozymes: Crystal-Facet-Dependent Enzyme-Mimetic Activity of V2O5 Nanomaterials
Ghosh, Sourav,Roy, Punarbasu,Karmodak, Naiwrit,Jemmis, Eluvathingal D.,Mugesh, Govindasamy
, p. 4510 - 4515 (2018)
Nanomaterials with enzyme-like activity (nanozymes) attract significant interest owing to their applications in biomedical research. Particularly, redox nanozymes that exhibit glutathione peroxidase (GPx)-like activity play important roles in cellular signaling by controlling the hydrogen peroxide (H2O2) level. Herein we report, for the first time, that the redox properties and GPx-like activity of V2O5 nanozyme depends not only on the size and morphology, but also on the crystal facets exposed on the surface within the same crystal system of the nanomaterials. These results suggest that the surface of the nanomaterials can be engineered to fine-tune their redox properties to act as “nanoisozymes” for specific biological applications.
Direct electrochemistry of glucose oxidase and sensing of glucose at a glassy carbon electrode modified with a reduced graphene oxide/fullerene-C60 composite
Thirumalraj, Balamurugan,Palanisamy, Selvakumar,Chen, Shen-Ming,Yang, Cheng-Yu,Periakaruppan, Prakash,Lou, Bih-Show
, p. 77651 - 77657 (2015)
In the present work, a glucose biosensor was fabricated based on the direct electrochemistry of glucose oxidase at glassy carbon modified with a reduced graphene oxide (RGO) and fullerene-C60 (C60) composite. The reduced graphene oxide/fullerene (RGO-C60) composite was prepared by electrochemical reduction of a graphene oxide (GO) and C60 composite at -1.4 V for 200 s in pH 5 solution; while the GO-C60 composite was prepared by a simple sonication of C60 in GO solution for 6 hours at 45°C. A well-defined and enhanced reversible redox peak of GOx was observed at RGO-C60 composite compared with other modified electrodes. The heterogeneous electron transfer rate constant (Ks) and the surface coverage concentration of GOx at RGO-C60/GOx modified electrode were calculated to be 2.92 s-1 and 1.19 × 10-10 mol cm-2, respectively. Under optimum conditions, the amperometry response of the biosensor was linear against the concentration of glucose from 0.1 to 12.5 mM with a response time of 3 s. The limit of detection was estimated to be 35 μM based on S/N = 3 with a high sensitivity of 55.97 μA mM-1 cm-2. In addition, the fabricated biosensor showed a good practical ability for the detection of glucose in human blood serum samples.
A Breathing Atom-Transfer Radical Polymerization: Fully Oxygen-Tolerant Polymerization Inspired by Aerobic Respiration of Cells
Enciso, Alan E.,Fu, Liye,Russell, Alan J.,Matyjaszewski, Krzysztof
, p. 933 - 936 (2018)
The first well-controlled aqueous atom-transfer radical polymerization (ATRP) conducted in the open air is reported. This air-tolerant ATRP was enabled by the continuous conversion of oxygen to carbon dioxide catalyzed by glucose oxidase (GOx), in the presence of glucose and sodium pyruvate as sequential sacrificial substrates. Controlled polymerization using initiators for continuous activator regeneration (ICAR) ATRP of oligo(ethylene oxide) methyl ether methacrylate (OEOMA, Mn=500) yielded polymers with low dispersity (1.09≤?≤1.29) and molecular weights (MWs) close to theoretical values in the presence of pyruvate. Without added pyruvates, lower MWs were observed due to generation of new chains by H2O2 formed by reaction of O2 with GOx. Successful chain extension of POEOMA500 macroinitiator with OEOMA300 (?≤1.3) and Bovine Serum Albumin bioconjugates (?≤1.22) confirmed a well-controlled polymerization. The reactions in the open air in larger scale (25 mL) were also successful.
Design and development of Co3O4/NiO composite nanofibers for the application of highly sensitive and selective non-enzymatic glucose sensors
Ramasamy, Ramachandran,Ramachandran,Philip, Geo George,Ramachandran, Rasu,Therese, Helen Annal,Gnana Kumar
, p. 76538 - 76547 (2015)
Cobaltosic oxide/nickel oxide (Co3O4/NiO) composite nanofibers were synthesized via an electrospinning technique and their electrocatalytic activities toward non-enzymatic glucose sensors were evaluated in detail. The Co3O4/NiO composite exhibited the homogeneously distributed nanofibers with high porosity, effective inter connectivity and an extended number of conducting channels with an average diameter of 160 nm. The diffraction patterns depicted the face centred cubic crystalline structure of Co3O4/NiO nanofibers and the purity of the composite nanofibers was further ensured by using FT-IR and UV-vis spectroscopic analyses. The electrocatalytic performances of prepared nanofibers toward the oxidation of glucose was determined by cyclic voltammetry and amperometry techniques and the experimental results showed that the Co3O4/NiO composite nanofibers exhibited a maximum electrooxidation toward glucose, owing to the synergistic effect of Co3O4 and NiO. The electrospun Co3O4/NiO nanofibers exhibited a detection limit of 0.17 μM, a wide linear range of 1 μM to 9.055 mM and a high sensitivity of 2477 μA mM-1 cm-2. The nanofibers have also exhibited favorable properties such as good selectivity, reproducibility, durability and real sample analysis, which ensured its potential applications in the clinical diagnosis of diabetes.
Versatile Three-Dimensional Porous Cu@Cu2O Aerogel Networks as Electrocatalysts and Mimicking Peroxidases
Ling, Pinghua,Zhang, Qiang,Cao, Tingting,Gao, Feng
, p. 6819 - 6824 (2018)
A facile strategy is presented to form 3D porous Cu@Cu2O aerogel networks by self-assembling Cu@Cu2O nanoparticles with the diameters of ca. 40 nm for constructing catalytic interfaces. Unexpectedly, the prepared Cu@Cu2O aerogel networks display excellent electrocatalytic activity to glucose oxidation at a low onset potential of ca. 0.25 V. Moreover, the Cu@Cu2O aerogels also can act as mimicking-enzymes including horseradish peroxidase and NADH peroxidase, and show obvious enzymatic catalytic activities to the oxidation of dopamine (DA), o-phenyldiamine (OPD), 3,3,5,5-tetramethylbenzidine (TMB), and dihydronicotinamide adenine dinucleotide (NADH) in the presence of H2O2. These 3D Cu@Cu2O aerogel networks are a new class of porous catalytic materials as mimic peroxidases and electrocatalysts and offer a novel platform to construct catalytic interfaces for promising applications in electrochemical sensors and artificial enzymatic catalytic systems.
