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 A. Sauret, E. C. Barney, A. Perro, E. Villermaux, H. A. Stone and E. Dressaire  Applied Physics Letters 2014, 105, 074101  We report on a microfluidic method that allows measurement of a small...
Thumbnail D. Tarus, E. Hachet, L. Messager, B. Catargi, V. Ravaine, R. Auzély-Velty Macromol. Rapid. Commun. 2014, 35, 2089 -2095 Dynamic covalent hydrogels are facilely prepared from biocompatible...
Thumbnail P. Masse, E. Sellier, V. Schmitt, and V. Ravaine Langmuir, 2014, 30 (49), pp 14745–14756 The importance of electrostatics on microgel adsorption at a liquid interface is studied, as well as its...
Thumbnail H. Sopha, J. Roche, I. Švancara, A. Kuhn Anal.Chem. 2014, 86, 10515–10519 In this contribution, a wireless method for the electrolytic sampling of heavy metals at special bismuth-modified...
Thumbnail J. Roche, S. Carrara, J. Sanchez, J. Lannelongue, G. Loget, L. Bouffier, P. Fischer, A. KuhnSci. Rep. 2014, 4, 6705 Miniaturized structures that can move in a controlled way in solution and...
Thumbnail F. Pinaud, N. Sojic, V. Ravaine L'Actualité Chimique, 2014, 390. In the present work, redox thermoresponsive microgels bearing ruthenium complex were synthesized. Investigation of electrogenerated...
Thumbnail J. Roche, E. Gianessi, A. KuhnPhys. Chem. Chem. Phys. 2014, 16, 21234-21236. Here we report a new physico-chemical method based on bipolar electrochemistry for producing spherical metal beads with...
Thumbnail M. Ongaro, J. Roche, A. Kuhn, P. UgoChem. Electro. Chem. 2014, 2048-2051 We present a new procedure for the site-specific deposition of metal on semiconductor nanofibers (NF). The semiconductor...
Thumbnail M. Sentic, S. Arbault, B. Goudeau, D. Manojlovic, A. Kuhn, L. Bouffier, N. SojicChem. Commun. 2014, 50, 10202-10205. An electrochemiluminescent (ECL) swimmer driven by bipolar...
Thumbnail E. Suraniti, S. Ben-Amor, P. Landry, M. Rigoulet, E. Fontaine, S. Bottari, A. Devin, N. Sojic, N. Mano, S. ArbaultAngew. Chem. Int. Ed. 2014, 126, 6773-6776.Mitochondria consume oxygen at the...
Thumbnail S. Kong, O. Fontaine, J. Roche, L. Bouffier, A. KuhnD. ZigahLangmuir 2014, 30, 2973−2976 Bipolar electrochemistry has been recently explored for the modification of conducting micro- and...
Thumbnail F. Pinaud, K. Geisel, P. Massé, B. Catargi, L. Isa, W. Richtering, V. Ravaine, V. SchmittSoft Matter, 2014, in press. The aim of this paper is to determine how microgels adsorb at a model...
Thumbnail Bouffier L., Doneux T., Goudeau B., Kuhn A.Anal. Chem. 2014, 86(8) 3708-3711. Bipolar electrochemistry (BPE) is nowadays well-known but relatively underexploited and still considered as...
Thumbnail Yadnum S., Roche J., Lebraud E., Négrier P., Garrigue P., Bradshaw D., Warakulwit C., Limtrakul J., Kuhn A. Angew. Chem. Int. Ed. 2014, 126, 4082-4086. Herein, bipolar electrochemistry is...
Thumbnail Sentic, M., Milutinovic, M., Kanoufi, F., Manojlovic, D., Arbault S., Sojic, N.Chem. Sci. 2014, 5, 2568-2572. The remarkable characteristics of electrogenerated chemiluminescence (ECL) as a...
Thumbnail Wattanakit C., Bon Saint-Côme Y., Lapeyre V., Bopp P., Heim M., Yadnum S., Nokbin S., Warakulwit C., Limtrakul J., Kuhn A.Nature Comm.2014, 5,article 3325. Chirality is widespread in natural...
Thumbnail Roche J., Loget G., Zigah D., Fattah Z., Goudeau B., Arbault S., Bouffier L., Kuhn A.Chem. Sci. 2014, 5, 1961-1966 Particles with sophisticated surface patterns have many potential...
Thumbnail Destribats M., Lapeyre V., Sellier E., Varga I., Ravaine V., Schmitt V.Langmuir 2014, 30, 1768-1777. We study the influence of the particle size on the ability of poly(N-isoprolylacrylamide)...
Thumbnail Ongaro M., Gambirasi A., Favaro M., Kuhn A., Ugo P.Electrochim. Acta2014, 116,421. This contribution presents the asymmetrical modification of carbon microfibers (CMF) with gold and...
Thumbnail Hachet E., Sereni N., Pignot-Paintrand I., Ravaine V., Szarpak-Jankowska A., Auzély-Velty R.J. Coll. Interface Sci. 2014, 419, 52-55. The fabrication of hyaluronic acid (HA) nanogels using a...
Thumbnail Ben-Amor S., Vanhove E., Sékli Belaïdi F., Charlot S., Colin D., Rigoulet M., Devin A., Sojic N., Launay J., Temple-Boyer P., Arbault S. Electrochimica Acta 2014, ASAP article Black...
Thumbnail Bouffier L., Wang B. S., Roget A., Livache T., Demeunynck M., Mailley P.Anal. Bioanal. Chem. 2014, 406(4), 1163-1172. A synthetic redox probe structurally related to natural pyridoacridones was...
Thumbnail Vajrala V. S., Suraniti E., Garrigue P., Goudeau B., Rigoulet M., Devin A., Sojic N., Arbault S.Anal. Bioanal. Chem. 2014, 406, 931-941. Forefront Paper Microsystems based on microwell arrays...
Thumbnail Bouffier L., Zigah D., Adam C., Sentic M., Fattah Z., Manojlovic D., Kuhn A., Sojic N.ChemElectroChem 2014, 1(1), 95-98. A blue-light-emitting swimmer driven by bipolar electrochemistry is...