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 chemiluminescent properties shows an unexpected amplification up to two orders of magnitude at the volume phase transition. The origin of this phenomenon is explained by the decrease in the average distance between adjacent ruthenium complexes at the swell-collapse transition, which favors the annihilation process in the microgels. This general principle offers the opportunity to develop a new range of electrogenerated chemiluminescent biosensors based microgels.

2014-19

 

Clogging by sieving in microchannels: application to the detection of contaminants in colloidal suspensions
vendredi 8 avril 2016
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 concentration of largecontaminants in suspensions of solid micrometer-scale particles. To perform... Read More...
Readily Prepared Dynamic Hydrogels by Combining Phenyl Boronic Acid- and Maltose-Modified Anionic Polysaccharides at Neutral pH
vendredi 19 décembre 2014
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 polysaccharides in physiological conditions by the formation of phenylboronate ester cross-links. This is based on the simple mixing of carboxylate-containing polysaccharides (i.e., hyaluronic acid or... Read More...
Impact of Electrostatics on the Adsorption of Microgels at the Interface of Pickering Emulsions
vendredi 19 décembre 2014
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 consequence on emulsion stabilization. In this work, poly(N-isopropylacrylamide) (pNIPAM) microgels bearing different numbers of charges and various distribution profiles are studied, both in solution... Read More...
Wireless Electrosampling of Heavy Metals for Stripping Analysis with Bismuth-Based Janus Particles
mercredi 19 novembre 2014
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 particles is presented. For the first time, glassy carbon beads were asymmetrically modified with bismuth using bipolar electrochemistry. The resulting chemically asymmetric beads, so-called Janus particles,... Read More...
Wireless powering of e-swimmers
mardi 21 octobre 2014
J. Roche, S. Carrara, J. Sanchez, J. Lannelongue, G. Loget, L. Bouffier, P. Fischer, A. Kuhn Sci. Rep. 2014, 4, 6705 Miniaturized structures that can move in a controlled way in solution and integrate various functionalities are attracting considerable attention due to the potential applications in fields ranging from autonomous micromotors to roving sensors. Here we introduce a concept which... Read More...
Stimuli-responsive microgels for electrochemiluminescence amplification
mardi 7 octobre 2014
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 chemiluminescent properties shows an unexpected amplification up to two orders of magnitude at the volume phase transition. The origin of this phenomenon is explained by the decrease in the average...
Physico-chemical Milling for controlled Size Reduction of Metal Beads
jeudi 28 août 2014
J. Roche, E. Gianessi, A. Kuhn Phys. 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 a well-controlled size. Applying an electric field to a low conductivity electrolyte containing metal beads leads to a polarization potential across the beads which triggers their electrodissolution.... Read More...
Asymmetric Modification of TiO2 Nanofibers with Gold by Electric-Field-Assisted Photochemistry
jeudi 31 juillet 2014
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 NFs are exposed to an external electric field while irradiated with UV light. This coupling allows the generation of excited electron–hole couples and drives them to the opposite extremities of the... Read More...
Electrochemiluminescent Swimmers for Dynamic Enzymatic Sensing
lundi 30 juin 2014
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 electrochemistry is reported for enzymatic glucose sensing. The chemo-mechanical motion is induced by localized hydrogen bubble generation. The concomitant oxidation of the luminophore and of the enzymatically-produced NADH... Read More...
Monitoring Electrochemically the Early Events of Hydrogen peroxide Production by Mitochondria
jeudi 22 mai 2014
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 respiratory chain and convert redox energy into ATP. As a side process, they produce reactive oxygen species (ROS), which physiological activities still need to be understood. However, current analytical... Read More...
Electropolymerization of Polypyrrole by Bipolar Electrochemistry in an Ionic Liquid
mardi 13 mai 2014
S. Kong, O. Fontaine, J. Roche, L. Bouffier, A. Kuhn, D. ZigahLangmuir 2014, 30, 2973−2976 Bipolar electrochemistry has been recently explored for the modification of conducting micro- and nanoobjects with various surface layers. So far, it has been assumed that such processes should be carried out in low-conductivity electrolytes in order to be efficient. We report here the first bipolar... Read More...
Adsorption of Microgels at an Oil–Water Interface: Correlation between Packing and 2D Elasticity
vendredi 25 avril 2014
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 oil–water interface and how they adapt their conformation to compression, which gives rise to surface elasticity depending on the microgel packing. The structure of the film is determined by the Langmuir... Read More...
Imaging Redox Activity at Bipolar Electrodes by Indirect Fluorescence Modulation
vendredi 21 mars 2014
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 unconventional. It has been used, among others, in the frame of materials science and most importantly has also found very promising applications in analytical chemistry. Here, we extend this emerging field of... Read More...
Site-Selective Synthesis of Janus-type Metal-Organic Framework Composites
jeudi 6 mars 2014
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 applied in a straightforward way to the site-selective in situ synthesis of metal–organic framework (MOF) structures, which have attracted tremendous interest in recent years because of their significant... Read More...
Mapping the Electrogenerated Chemiluminescence Reactivity in Space: Mechanistic Insight into Model Systems Used in Immunoassays
lundi 3 mars 2014
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 readout method are successfully exploited in numerous microbead-based immunoassays. However there is still a lack of understanding of the extremely high sensitivity of such ECL bioassays. Here the mechanisms... Read More...
Enantioselective Recognition at Mesoporous Chiral Metal Surfaces
mercredi 19 février 2014
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 systems, and artificial reproduction of chiral recognition is a major scientific challenge, especially owing to various potential applications ranging from catalysis to sensing and separation science. In... Read More...
Straight-forward Synthesis of Ringed Particles
jeudi 23 janvier 2014
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 applications ranging from information coding to catalysis and optics. However controlled patterning of particles often requires rather complicated lithographic or template based approaches. Here we report the... Read More...
Impact of pNIPAM Microgel Size on their Ability to stabilize Pickering Emulsions
mercredi 22 janvier 2014
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) microgels to stabilize direct oil-in-water Pickering emulsions. The microgel size is varied from 250 to 760 nm, the cross-linking density being kept constant. The emulsion properties strongly depend on the... Read More...
Asymmetrical Modification of Carbon Microfibers by Bipolar Electrochemistry in Acetonitrile
vendredi 10 janvier 2014
Ongaro M., Gambirasi A., Favaro M., Kuhn A., Ugo P.Electrochim. Acta 2014, 116, 421. This contribution presents the asymmetrical modification of carbon microfibers (CMF) with gold and polythiophene by bipolar electrochemistry (BPE) in acetonitrile (ACN). At first, the electrochemical behavior of AuCl4- in ACN was examined by cyclic voltammetry, in order to determine the deposition mechanism and... Read More...
Thiol-ene Clickable Hyaluronans: from Macro- to Nanogel
mercredi 25 décembre 2013
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 thiol-ene reaction has been demonstrated. HA was modified with pentenoate groups and then cross-linked with poly(ethylene glycol)-bis(thiol) by exposure to UV light. The cross-linking density and thereby the... Read More...
Enhanced Detection of Hydrogen Peroxide with Platinized Microelectrode Arrays for Analyses of Mitochondria Activities
dimanche 1 décembre 2013
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 platinum-modified ultramicroelectrodes (UME) were previously reported as excellent sensors for hydrogen peroxide produced by biological systems; their detection limit being typically 100 nM. In the present... Read More...
Electrochemical Transduction of DNA Hybridization at Modified Electrodes by using an Electroactive Pyridoacridone Intercalator
jeudi 12 septembre 2013
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 designed and electrochemically characterised. These heterocycles behave as DNA intercalators due to their extended planar structure that promotes stacking in between nucleic acid base pairs.... Read More...
Optical Microwell Array for Large Scale Studies of Single Mitochondria Metabolic Responses
dimanche 28 juillet 2013
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 have been widely used for studies on single living cells. In this work, we focused on the subcellular level in order to monitor biological responses directly on individual organelles. Consequently, we... Read More...
Lighting up Redox Propulsion with Luminol Electrogenerated Chemiluminescence
lundi 8 juillet 2013
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 reported here for the first time. The approach involves the controlled motion of a conducting carbon bead through localized oxygen bubble generation, resulting from the oxidation of hydrogen peroxide.... Read More...