A particularly efficient redox mediator for electron transfer between FAD-dependent glucose dehydrogenase (FAD-GDH) and carbon nanotube (CNT) based electrodes can be obtained via electrosynthetic oxidation of pyrene in aqueous buffer solution. 1 H-NMR spectroscopic studies reveal the formation of a 2 : 1 mixture of 1,6-pyrenedione and 1,8-pyrenedione at the electrode. The formed pyrenedione exhibits a well-defined surface-bound redox system at À 0.1 V vs. SCE and provides excellent electron transfer kinetics with this enzyme. Further-more, the π-system of pyrenedione allows improved stacking behavior with the CNT walls, leading to enhanced stabilities compared to commonly used mediators like naphthoquinone. The electrosynthesis of pyrenedione for catalytic glucose oxidation is optimal at pH 2 using cyclic voltammetry or chronoamerometry. It is envisioned that the electrosynthetic methodology can be expanded to form different redox mediators for a series of enzymes.[a] Dr.

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Biosensors are essential tools in the health and the environmental sectors since they allow fast and reliable diagnostics and analysis. Biosensors are defined by the biological sensing element, which contains biomolecules or synthetic, bioinspired entities with unique specificity towards the analyte. The biological or bioinspired recognition even can be transduced into an electric, electrochemical, or optical signal. A constant challenge for the development of biosensors is the confinement of these selective entities in devices without altering the biological activity. Polymers are great candidates to serve as substrates for the immobilization or entrapment of bioreceptors related to well established synthesis routes with highly modulable chemical functions to create an almost ideal environment for the biomolecules. Nanomaterials are of constant increasing interest since they allow not only to increase drastically the specific surface for higher amounts of receptor units, but also provide electric or optical properties leading to enhanced signal capture. As for bioreceptors, such nanomaterials can be integrated polymer matrices for reliable processability. This review aims to summarize selected original examples about biosensors for health monitoring using beneficial combinations of nanomaterials and polymers.

A series of polycyclic aromatics, naphthalene, phenanthrene, perylene, pyrene, 1-pyrenebutyric acid N-hydroxysuccinimide ester (pyrene NHS) and coronene, were immobilized via π stacking on carbon nanotube (CNT) electrodes and electro-oxidized in...

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Thanks to an increased surface area, nanomaterials such as carbon nanotubes, graphene, [5][6][7][8][9][10][11][12][13] semi-conductor quantum dots, [14,15] have significantly increased the power density of biofuel cells and capacitors as well as the analytical performance of biosensors in terms of sensitivity and detection limit. In addition, metallic nanoparticles [16][17][18] have aroused great interest in the elaboration of electrode materials due to their physical and chemical properties such as high surface/volume ratio and relatively high electrical conductivity. Their main drawback lies in the post-chemical treatment of their surface to obtain reactive groups such as carboxyl, thiol, or amino groups, for example, for anchoring biomolecules. These steps are often complex and time consuming. [19] Recently, an attractive alternative to these metallic nanoparticles has been reported and consists of organic nanoparticles generated by selfassembly of amphiphilic glycopolymers in water. In particular, glyconanoparticles (GNPs) composed of polystyrene-block-βcyclodextrin (PS-b-βCD) constitute in aqueous medium, stable and polyvalent nanospheres easily functionalizable by inclusion of hydrophobic compounds in the cavities of the β-cyclodextrin shell. These host-guest interactions of the nanoparticle shell have been used successfully to immobilize redox hydrophobic compounds such tetrazine-naphthalimide, [20] bispyrene-(2,2′azino-bis(3-ethylbenzothiazoline-6-sulfonic acid), [21] phenanthrene-quinone, [22] anthraquinone-sulfonate. [23] Some of these resulting redox nanoparticles were applied in suspension successfully for efficient electrical connection of enzymes and the development of a solubilized enzymatic fuel cells. [22] However, these GNPs have only been used in aqueous suspension and have never been tested as a building block for the design of nanostructured (bio)materials of electrode for biosensing application or energy conversion. In this context, we report here the possibility to attach these nanoparticles on an electrode surface by specific host-guest interactions and compared this approach to a simple adsorption. Owing to the high affinity of adamantane to form inclusion complexes with Glyconanoparticles (GNPs) made by self-assembly of carbohydrate-based polystyrene-block-β-cyclodextrin copolymer are used as a building block for the design of nanostructured biomaterials of electrode. The firm immobilization of GNPs is carried out on electrochemically generated polymer, poly(pyrroleadamantane), and copolymer, poly(pyrrole-adamantane)/poly(pyrrole-lactobionamide) via host-guest interactions between adamantane and β-cyclodextrin. The ability of GNPs for the specific anchoring of biological macromolecules is investigated using glucose oxidase enzyme modified by adamantane groups as a protein model (GOx-Ad). The immobilization of GOx-Ad is carried out by incubation of an aqueous enzyme solution on a coating of GNPs adsorbed on a platinum electrode. The presence of immobilized GOx-Ad is evaluated in aqueous g...

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