Bouffier L., Yiu H. H. P., Rosseinsky M. J.
Langmuir 2011, 27, 6185-6192.

Spherical magnetite nanoparticles (MNPs, 24 nm in diameter) were sequentially functionalized with trimethoxysilylpropyldiethylenetriamine (TMSPDT) and a synthetic DNA intercalator, namely, 9-chloro-4H-pyrido[4,3,2-kl]acridin-4-one (PyAcr), in order to promote DNA interaction. The designed synthetic pathway allowed control of the chemical grafting efficiency to access MNPs either partially or fully functionalized with the intercalator moiety. The newly prepared nanomaterials were characterized by a range of physicochemical techniques: FTIR, TEM, PXRD, and TGA. The data were consistent with a full surface coverage by immobilized silylpropyldiethylenetriamine (SPDT) molecules, which corresponds to 22300 SPDT molecules per MNP and a subsequent (4740 − 2940) PyAcr after the chemical grafting step (i.e., 2.4 PyAcr/nm2). A greater amount of PyAcr (30600) was immobilized by the alternative strategy of binding a fully prefunctionalized shell to the MNPs with up to 16.1 PyAcr/nm2. We found that the extent of PyAcr functionalization strongly affects the resulting properties and, particularly, the colloidal stability as well as the surface charge estimated by ζ-potential measurement. The intercalator grafting generates a negative charge contribution which counterbalances the positive charge of the single SPDT shell. The DNA binding capability was measured by titration assay and increases from 15 to 21.5 μg of DNA per mg of MNPs after PyAcr grafting (14−20% yield) but then drops to only 2 μg for the fully functionalized MNPs. This highlights that even if the size of the MNPs is obviously a determining factor to promote surface DNA interaction, it is not the only limiting parameter, as the mode of binding and the interfacial charge density are essential to improve loading capability.

 

 

Lenz J., Trieu V., Hempelmann R., Kuhn A.
Electroanalysis 2011, 23, 1186-1192.

We report two methods to prepare ordered macroporous ruthenium oxide electrodes based on a template approach and their possible applications as potentiometric and amperometric sensors. The very stable porous electrodes have been prepared using two techniques to assemble the colloidal template: the controlled evaporation (CE) technique and the Langmuir-Blodgett (LB) technique, followed by electrochemical deposition of ruthenium oxide. The increased surface area of the macroporous structure makes them attractive for electroanalytical applications such as potentiometric and amperometric sensors as is illustrated for pH sensing and direct oxidation of NADH, which is an ingredient in dehydrogenase based biosensors.

2011-10

Mertins O., Messina P., Labbé E., Arbault S., Lemaitre F., Buriez O., Amatore C.
Inorganica Chimica Acta 2011, 374(1), 59-68

Transport, reactivity and interactions of anti-tumor ferrocene-based compounds within lipid environments have been investigated electrochemically at a glassy carbon electrode (GCE) modified with a lipid bilayer film. Cyclic voltammetry performed in the presence of an adsorbed bilipid film in a H2O/EtOH (8/2) mixture, clearly showed that the affinity of the starting neutral ferrocifen derivatives towards the lipidic bilayer depends on both their size and their polarity. Likewise, the electrogenerated ferrocenium derivatives were expulsed reversibly from the bilayer in agreement with their positive charge. The reactivity of ferrocifen compounds was also investigated under the same conditions and in the presence of a base in order to trigger an intramolecular ferrocene-mediated (−2e −2H+) process within the lipidic film. Under these conditions, two distinct sequential electrochemical behaviors were observed depending on the base availability in the lipid layer, the magnitude of the corresponding two electrons wave being limited by the base concentration in the film. A full two-electron oxidation process, was observed as long as the amount of base present into the lipid layer was high enough to titrate the two protons released in the two-electron process. When this was sub-stoichiometric a second wave was observed at higher potential values representing the one electron oxidation of the ferrocifen excess.

2011-13

Loget G., Lapeyre V., Garrigue P., Warakulwit C., Limtrakul J., Delville M.-H., Kuhn A.
Chem.Mater. 2011, 23, 2595-2599

A bulk procedure based on bipolar electrochemistry is proposed for the generation of Janus-type carbon tubes. The concept is illustrated with carbon tubes, that are selectively modified at their ends with various metals and conducting polymers. No surface or interface is required to break the symmetry and therefore this approach could be used for the mass production of Janus micro- and nanoobjects. We show evidence that the technique is very versatile, allowing to choose the kind of material that is deposited and whether the end product is mono- or bifunctionalized.

2011-12

Meunier A., Jouannot O., Fulcrand R., Fanget I., Bretou M., Karatekin E., Arbault S., Guille M., Darchen F., Lemaitre F., Amatore C.
Angew. Chem. Int. Ed. 2011, 50(22), 5081-5084

A microdevice based on transparent indium tin oxide (ITO) electrodes allows simultaneous total internal reflection fluorescence microscopy and amperometric measurements. Use of the device in the coupled optical and electrochemical detection of single exocytotic events is demonstrated with enterochromaffin BON cells.

2011-14

Thumbnail Loget G., Kuhn A.Nature Comm. 20112, 535 Externally triggered motion of small objects shows a general promise in applications ranging from micromachines to drug delivery and self-assembly of...
Thumbnail Loget G., Kuhn A.G.I.T. Laboratory Journal 20115-6, 19-21. Bipolar electrochemistry is a concept with a quite long history, but has only very recently revealed its virtues in the field...
Thumbnail Couedelo L., Vaysse C., Guy A., Gosse I., Durant T., Pinet S., Simon N., Cansell M., Combe N.Lipid Nutri+ 2011, 12 La dernière édition des apports nutritionnels conseillés pour la population...
Thumbnail Destribats M., Lapeyre V., Sellier E., Leal-Calderon F., Schmitt V., Ravaine V.Langmuir 2011, 27(23), 14096-14107 Emulsions were prepared using poly(N-isopropylacrylamide) microgels as...
Thumbnail Peyrard L., Chierici S., Pinet S., Batat P., Jonusauskas G., Pinaud N., Meyrand P., Gosse I.Org. Biomol. Chem. 2011, 9, 8489-8494 A new strategy to obtain fluorescent cyclotriveratrylene (CTV) probes...
Thumbnail Loget G., Peyrard L., Ung V., Abadie T.L'Actualité Chimique 2011, 355, 50-51 La section Aquitaine de la Société Chimique de France inclut depuis janvier 2011 un club de jeunes chimistes qui a...
Thumbnail Bon Saint-Côme Y., Lalo H., Wang Z., Etienne M., Gajdzik J., Kohring G-W., Walcarius A., Hempelmann R., Kuhn A.Langmuir 2011, 27, 12737-12744 We describe the elaboration of a multi-scale tailored...
Thumbnail Ancla C., Lapeyre V., Gosse I., Catargi B., Ravaine V.Langmuir 2011, 27, 12693-12701 We report on the synthesis of various glucose-responsive microgels based on N-alkylacrylamide derivatives and...
Thumbnail Sojic N., Kuhn A.Annales de la Société des Experts Chimistes de France 2011975, 35-41. Les capteurs sont devenus indispensables pour de nombreux aspects de notre vie avec des exemples...
Thumbnail Segan D., Vukicevic R. D., Segan S., Sojic N., Buriez O., Manojlovic D.Electrochimica Acta 201156, 9968-9972 Cyclic voltammetry and ultramicroelectrodes were used to investigate the kinetic...
Thumbnail Loget G., Kuhn A.GIT Laborfachzeitschrift2011, 4, 236. Die bipolare Elektrochemie hat zwar schon einen ziemlich langen Werdegang hinter sich, ihre Vorteile auf dem Gebiet der Nanowissenschaft...
Thumbnail Wang Z., Etienne M., Kohring G-W., Bon Saint-Côme Y., Kuhn A., Walcarius A.Electrochim. Acta.2011, 56, 9032 We report here that the electrochemically-assisted deposition (E-AD) of silica thin...
Thumbnail Olariu C. I., Yiu H. H. P., Bouffier L., Nedjadi T., Costello E., Williams S. R., Halloran C. M., Rosseinsky M. J.J. Mater. Chem.2011, 21, 12650-12659 Amine and carboxylic acid-bifunctionalized iron...
Thumbnail Destribats M., Lapeyre V, Wolfs M., Sellier E., Leal-Calderon F., Ravaine V., Schmitt V.Soft Matter 2011, 7, 7689-7698  We synthesised soft uncharged microgels made of...
Thumbnail Loget G., Kuhn A.Techniques de l'Ingénieur2011, 7,RE208 L'électrochimie bipolaire est une technique relativement peu connue qui attire de plus en plus l'attention de la communauté scientifique....
Thumbnail Milutinovic M., Suraniti E., Studer V., Mano N., Manojlovic D., Sojic N.Chem. Comm.2011, 47, 9125-9127 Photoinitiated polymerization is efficiently and rapidly carried out to immobilize...
Thumbnail Milutinovic M., Sallard S., Manojlovic D., Mano N., Sojic N.Bioelectrochemistry2011, 82, 63-68 In this work, we report a new sensing approach based on electrogenerated chemiluminescence (ECL) in an...
Thumbnail Meunier A., Jouannot O., Fulcrand R., Fanget I., Bretou M., Karatekin E., Arbault S., Guille M., Darchen F., Lemaitre F., Amatore C. Angew. Chem. Int. Ed. 2011, 50(22), 5081-5084 A microdevice based...
Thumbnail Mertins O., Messina P., Labbé E., Arbault S., Lemaitre F., Buriez O., Amatore C. Inorganica Chimica Acta 2011, 374(1), 59-68 Transport, reactivity and interactions of anti-tumor ferrocene-based...
Thumbnail Loget G., Lapeyre V., Garrigue P., Warakulwit C., Limtrakul J., Delville M.-H., Kuhn A. Chem.Mater.2011, 23, 2595-2599 A bulk procedure based on bipolar electrochemistry is proposed for the...
Thumbnail Bouffier L., Yiu H. H. P., Rosseinsky M. J.Langmuir 2011, 27, 6185-6192. Spherical magnetite nanoparticles (MNPs, 24 nm in diameter) were sequentially functionalized with...
Thumbnail Lenz J., Trieu V., Hempelmann R., Kuhn A. Electroanalysis2011, 23, 1186-1192. We report two methods to prepare ordered macroporous ruthenium oxide electrodes based on a template approach and their...
Thumbnail Scullion L., Doneux T., Bouffier L., Fernig D. G., Higgins S. J., Bethell D., Nichols R. J.J. Phys. Chem. C2011, 115, 8361-8368.Because electron transfer is often highly sensitive to bridge...
Thumbnail Loget G., Kuhn A.Anal. Bioanal. Chem.2011, 400, 1691-1704.Bipolar electrochemistry is a technique with a rather young history in the field of analytical chemistry. Being based on the...
Thumbnail Suraniti E., Studer V., Sojic N., Mano N.Anal. Chem.2011, 83, 2824–2828 Immobilization and electrical wiring of enzymes is of particular importance for the elaboration of efficient biosensors...
Thumbnail Amatore C., Arbault S., Guille M., Lemaitre F.Actualité Chimique 2011, 348-349, 25-31 La production de radicaux libres par les êtres vivants aérobiques a certainement une très mauvaise presse,...
Thumbnail Fattah Z., Loget G., Lapeyre V., Garrigue P., Warakulwit C., Limtrakul J., Bouffier L., Kuhn A. Electrochimica Acta2011, 56, 10562-10566. Autonomous microswimmers are of enormous interest not...
Thumbnail Urbanova V., Li Y., Vytras K., Yvert B., Kuhn A.J. Electroanal. Chem. 2011, 656(1-2), 91-95. In order to understand the dynamics of large neuronal networks, one of the challenges of nowadays...
Thumbnail Reculusa S., Heim M., Gao F., Mano N., Ravaine S., Kuhn A. Adv. Funct. Mater., 2011, 21, 691-698. Porous gold structures with a well-defined pore size and thickness are obtained through...
Thumbnail Qu F., Nasraoui R., Etienne M., Bon Saint-Côme Y., Kuhn A., Lenz J., Gajdzik J., Hempelmann R., Walcarius A.Electrochem. Comm.2011, 13, 138-142.Electro-assisted generation of ultra-thin silica films...