Serge Cosnier

Biomolecule immobilization on electrode surfaces by entrapment or attachment to electrochemically polymerized films. A review

The concept and potentialities of electrochemical procedures of biomolecule immobilization based on electropolymerized films are described. The biomolecule entrapment in conventional electrogenerated polymers such as polypyrrole, polyaniline or polyphenol is compared with an electrochemical procedure involving the adsorption of amphiphilic monomers and biomolecules before the polymerization step. Examples of organic phase enzyme electrode and electrical wiring of immobilized enzymes are presented. Furthermore, the construction of controlled architectures based on spatially segregated multilayers, exhibiting complementary biological activities is described. Then, the use of functionalized polymers bearing functional groups for the covalent binding of biomolecules is reported. Moreover, the attachment of biomolecules to biotinylated polymers through affinity interactions based on avidin-biotin bridge is presented.

Mediatorless high-power glucose biofuel cells based on compressed carbon nanotube-enzyme electrodes

Enzymatic fuel cells use enzymes to produce energy from bioavailable substrates. However, such biofuel cells are limited by the difficult electrical wiring of enzymes to the electrode. Here we show the efficient wiring of enzymes in a conductive pure carbon nanotube matrix for the fabrication of a glucose biofuel cell (GBFC). Glucose oxidase and laccase were respectively incorporated in carbon nanotube disks by mechanical compression. The characterization of each bioelectrode shows an open circuit potential corresponding to the redox potential of the respective enzymes, and high current densities for glucose oxidation and oxygen reduction. The mediatorless GBFC delivers a high power density up to 1.3 mW cm−2 and an open circuit voltage of 0.95 V. Moreover, the GBFC remains stable for 1 month and delivers 1 mW cm−2 power density under physiological conditions (5×10−3 mol l−1 glucose, pH 7). To date, these values are the best performances obtained for a GBFC.

Nanomaterials for biosensing applications: a review

A biosensor device is defined by its biological, or bioinspired receptor unit with unique specificities toward corresponding analytes. These analytes are often of biological origin like DNAs of bacteria or viruses, or proteins which are generated from the immune system (antibodies, antigens) of infected or contaminated living organisms. Such analytes can also be simple molecules like glucose or pollutants when a biological receptor unit with particular specificity is available. One of many other challenges in biosensor development is the efficient signal capture of the biological recognition event (transduction). Such transducers translate the interaction of the analyte with the biological element into electrochemical, electrochemiluminescent, magnetic, gravimetric, or optical signals. In order to increase sensitivities and to lower detection limits down to even individual molecules, nanomaterials are promising candidates due to the possibility to immobilize an enhanced quantity of bioreceptor units at reduced volumes and even to act itself as transduction element. Among such nanomaterials, gold nanoparticles, semi-conductor quantum dots, polymer nanoparticles, carbon nanotubes, nanodiamonds, and graphene are intensively studied. Due to the vast evolution of this research field, this review summarizes in a non-exhaustive way the advantages of nanomaterials by focusing on nano-objects which provide further beneficial properties than “just” an enhanced surface area.

Single Glucose Biofuel Cells Implanted in Rats Power Electronic Devices

We describe the first implanted glucose biofuel cell (GBFC) that is capable of generating sufficient power from a mammals body fluids to act as the sole power source for electronic devices. This GBFC is based on carbon nanotube/enzyme electrodes, which utilize glucose oxidase for glucose oxidation and laccase for dioxygen reduction. The GBFC, implanted in the abdominal cavity of a rat, produces an average open-circuit voltage of 0.57 V. This implanted GBFC delivered a power output of 38.7 μW, which corresponded to a power density of 193.5 μW cm−2 and a volumetric power of 161 μW mL−1. We demonstrate that one single implanted enzymatic GBFC can power a light-emitting diode (LED), or a digital thermometer. In addition, no signs of rejection or inflammation were observed after 110 days implantation in the rat.

A new strategy for the construction of a tyrosinase-based amperometric phenol and o-diphenol sensor

Abstract A novel biosensor construction based on the electropolymerization of a pyrrole amphiphilic monomer-tyrosinase (EC 1.14.18.1) mixture previously adsorbed on an electrode is described. The enzyme film was characterized and applied to the detection of several phenols and o -diphenols. The electrode response is based on the amperometric detection of the biocatalytically generated o -quinones. This biosensor has a fast reponse time (about 3 s) and provides very low detection limits (2 nM for catechol). Linear calibration curves were obtained over a wide concentration range. Their slopes, varying from 1 to 300 mA M −1 , illustrate the selectivity of the biosensor. The stability, pH and temperature response of the biosensor as well as its kinetic parameter have also been studied.

Electrosynthesized polymers for biosensing

This tutorial review briefly surveys the chronological evolution of biosensor concepts based on electrogenerated polymers. The most common procedures of biomolecule immobilization are classified as direct electropolymerization, physical entrapment, covalent linkage, and anchoring by affinity interactions via electropolymerized films. These are discussed, and recent bioanalytical applications are described. The discussion emphasizes the use of templates for controlling the formation of nanowires and composite polymers. Recent advances in the design of three-dimensional biological architectures are also highlighted.

A biosensor as warning device for the detection of cyanide, chlorophenols, atrazine and carbamate pesticides

Abstract The determination of cyanide, chlorophenols, atrazine, dithiocarbamate and carbamate pesticides is described, utilizing an amperometric biosensor constructed by the electropolymerization of a pyrrole amphiphilic monomer-tyrosinase coating. Measurements were carried out with catechol, dopamine, l -DOPA or epinephrine as an enzyme substrate; the enzymatically generated quinoid products being electroreduced at -200 mV vs. SCE. The detection of these water pollutants was performed via their inhibiting action on the tyrosinase electrode. The characterization of the inhibition processes (competitive /non-competitive) and their reversibility were examined. The detection limits are 0.4, 2, 2, 4 and 0.02 μM for 3,4-dichlorophenol, chloroisopropylphenylcarbamate, 3-chloroaniline, atrazine and cyanide, respectively.

Electrochemical coating of a platinum electrode by a poly(pyrrole) film containing the fac-Re (2,2'-bipyridine) (CO)3Cl system. Application to electrocatalytic reduction of CO2

Donnees sur la preparation et le comportement electrochimique des electrodes de Pt recouvertes de films de polypyrrole contenant des complexes de Re(I) avec le bipyridyle

Oxidative electropolymerization of polypyridinyl complexes of ruthenium(II)-containing pyrrole groups

Abstract The oxidative electrochemical polymerization of polypyridinyl complexes of ruthenium(II) that contain pyrrolic groups on their surrounding ligands have been investigated. Film formation and stability of the resulting modified electrodes have been studied with regard to the number of pyrrolic groups and 2,2′-bipyridinyl ligands contained in the complexes. Observation of prepeaks in the cyclic voltammograms of the modified electrodes is attributed to the mediated oxidation and reduction of the polypyrrole backbone through the redox levels of the Ru(II) complexes. The polypyrrolic chain does not exhibits its usual electroactivity, probably owing to the steric hindrance due to the bulky polypyridinyl Ru(II) pendant groups.

Impedimetric immunosensor using avidin–biotin for antibody immobilization

The potentialities of an electrodeposited biotinylated polypyrrole film as an immobilisation matrix for the fabrication of impedimetric immunosensors are described. Biotinylated antibody (anti-human IgG), used as a model system, was attached to free biotin groups on the electrogenerated polypyrrole film using avidin as a coupling reagent. This immobilization method allows to obtain a highly reproducible and stable device. The resulting immunosensor has a linear dynamic range of 10-80 ng ml(-1) of antigen and a detection limit of 10 pg ml(-1). Furthermore, this immunosensor exhibited minor loss in response after two regeneration steps.