J. Kalecki, M. Cieplak, M. Dąbrowski, W. Lisowski, A. Kuhn,  P. Sindhu Sharma

ACS Sensors (2019) in press, doi.org/10.1021/acssensors.9b01878

Homogenous nanostructuration of molecularly imprinted polymer (MIP) films for follicle-stimulating hormone (FSH) sensing was achieved by using optimized colloidal crystals as a hard mold. Introduction of heating step after assembling colloidal crystals of silica beads promoted their adhesion.  Thus precise assembling of beads was not disturbed during further multistep of surface imprinting, and crack free hexagonal packing was maintained.  SEM imaging confirmed hexagonal packing of silica colloidal crystals as well as homogenous nanostructurization in MIP films. FSH immobilization over silica beads and later its derivatization with electroactive functional monomers was confirmed by XPS analysis. The nanostructured molecular recognition films prepared in this way were combined with an electrochemical transducer in order to design a capacitive impedimetry (CI) based chemosensing system. It was tested for the determination of FSH in the range from 0.1 fM to 100 pM in 10 mM MES buffer (pH = 4.2).  The detection limit of the chemosensor was 0.1 fM showing a high selectivity with respect to common protein interferences as well as other protein hormones of the gonadotropin family.

2019 21

 

C. Wattanakit, A. Kuhn

Chemistry-A European Journal (2019) in press

The concept of encoding molecular information in bulk metals has been proposed over the past decade. The structure of various types of molecules has been imprinted, including also enantiomers. Typically, to encode metals with chiral information, several approaches, based on chemical and electrochemical concepts, can be used. In this minireview we discuss recent achievements with respect to the development of such materials, including the entrapment of chiral biomolecules in metals, the chiral imprinting of metals, as well as the combination of imprinting with nanostructuring. The features and potential applications of these designer materials, such as chirooptical properties, enantioselective adsorption and separation as well as their use for asymmetric synthesis will be presented. This will illustrate that the development of molecularly encoded metal structures opens up very interesting perspectives, especially in the frame of chiral technologies.

2019 19

T. Bombail, P. Garrigue, B. Goudeau, D. Talaga, L. Bouffier, S. Bonhommeau, L. Servant, D. Zigah, S. Arbault, N. Sojic

Electrochim. Acta, 2019, DOI: 10.1016/j.electacta.2019.135105.

Gold microelectrodes decorated with nanotips were developed for spectroelectrochemical experiments. These new dual probes were fabricated by combining fabrication processes of scanning near-field optical microscopy with photolithography. A nanotip array was produced at the surface of a coherent optical fiber bundle by a wet chemical etching step. The resulting nanostructured surface was sputter-coated with a thin gold layer. This gold film conferred plasmonic properties to the sharp nanotips and served as well as the electrode material to enable electrochemical reactions. A photolithographic process was used to define on the bundle surface nanotips-decorated microelectrodes with tunable dimensions (radii ranging between 20 μm and 3.5 μm) individually or in an array format. The resulting microelectrodes with a regular nanotip pattern were characterized first by cyclic voltammetry. Numerical simulation was used to assess the electrochemical properties of these platforms and the influences of the recessed geometry and of the nanotips. Approach curves were recorded in negative and positive feedback modes of scanning electrochemical microscopy (SECM) on insulating and conducting substrates. Finally, spatially resolved Raman imaging allowed us to detect a mercaptobenzoic acid monolayer adsorbed on the microelectrode surface, demonstrating a surface-enhanced Raman scattering (SERS) effect induced by the gold-coated nanotips with a typical enhancement factor of ∼7 × 104. Such an approach introduces a reproducible method to fabricate promising SERS-active platforms with microelectrode behavior for SECM experiments.

tips

S. Assavapanumat,  M. Ketkaew,  A. Kuhn, C.Wattanakit

J. Am.Chem.Soc. 141 (2019) 18870 (Front Cover)

see also CNRS press release

The enantioselective synthesis of chiral compounds is of crucial importance for a wide range of potential applications, especially in cosmetic and pharmaceutical industries. Recently, chiral imprinted mesoporous platinum films, produced by the electrodeposition of the metal, in the simultaneous presence of a lyotropic liquid crystalline phase of non-ionic surfactants as mesoporogens and chiral templates, have been applied as electrocatalysts and selective stationary phases for the asymmetric synthesis and separation of chiral compounds, respectively. However, platinum is an expensive metal and therefore it is mandatory to explore the possibility to apply this concept also to other metals. In this contribution, we propose mesoporous chiral imprinted nickel as an alternative cheap and earth-abundant metal. The designed surface layers not only demonstrate electrochemical discrimination between two enantiomers, but most importantly, also allow stereospecific electroreduction of a prochiral compound, with very significant enantioselectivity of up to 80% ee. These results open up very promising perspectives for the development of low cost non-noble metal matrices for the synthesis of chiral compounds.

2019 20

A. Bouchet-Spinelli, E. Descamps, J. Liu, A. Ismail, P. Pham, F. Chatelain, T. Leïchlé, L. Leroy, P. N. Marche, C. Raillon, A. Roget, Y. Roupioz, N. Sojic, A. Buhot, V. Haguet, T. Livache and P. Mailley

Biosensors 2019, 9, 121; doi:10.3390/bios9040121

This review summarizes recent advances in micro- and nanopore technologies with a focus on the functionalization of pores using a promising method named contactless electro-functionalization (CLEF). CLEF enables the localized grafting of electroactive entities onto the inner wall of a micro- or nano-sized pore in a solid-state silicon/silicon oxide membrane. A voltage or electrical current applied across the pore induces the surface functionalization by electroactive entities exclusively on the inside pore wall, which is a significant improvement over existing methods. CLEF’s mechanism is based on the polarization of a sandwich-like silicon/silicon oxide membrane, creating electronic pathways between the core silicon and the electrolyte. Correlation between numerical simulations and experiments have validated this hypothesis. CLEF-induced micro- and nanopores functionalized with antibodies or oligonucleotides were successfully used for the detection and identification of cells and are promising sensitive biosensors. This technology could soon be successfully applied to planar configurations of pores, such as restrictions in microfluidic channels.

micropore

Thumbnail S. Assavapanumat, T. Yutthalekha, P. Garrigue, B. Goudeau, V. Lapeyre, A. Perro, N. Sojic, C. Wattanakit, A. Kuhn Angew. Chem. Int. Ed. 58 (2019) 3471 (Back Cover) see also CNRS press release...
Thumbnail S. Voci, B. Goudeau, G. Valenti, A. Lesch, M. Jović, S. Rapino, F. Paolucci, S. Arbault, N. Sojic J. Am. Chem. Soc., 140,2018, 14753-14760 Herein is reported a surface-confined microscopy based...
Thumbnail Hanan Al-Kutubi, Silvia Voci, Liza Rassaei, Neso Sojic, Klaus Mathwig Chem .Sci., 9, 2018, (2018 Chemical Science HOT Article Collection) Microfabricated nanofluidic electrochemical devices offer a...
Thumbnail L. Bouffier, S. Arbault, A. Kuhn, N. Sojic Techniques de l’Ingénieur. 2018. P156 Les mesures sélectives et sensibles dans des échantillons complexes tels que l’urine ou le sang sont devenues des outils...
Thumbnail H. Labie, A. Perro, V. Lapeyre, B. Goudeau, B. Catargi, R. Auzély, V. Ravaine Journal of Colloid and Interface Science 535 (2019) 16–27 A simple route to deliver on demand hydrosoluble molecules such...
Thumbnail E.Krisch, B. Gyarmati, D. Barczikai, V. Lapeyre, B.A. Szilágyi, V. Ravaine, A. Szilágyi European Polymer Journal 105 (2018) 459–468 Redox and pH responsive hydrogels were synthesized, which can...
Thumbnail L. Zhang, B. Gupta, B. Goudeau, N. Mano, A. Kuhn J. Am. Chem. Soc 140 (2018) 15501 Collecting electrochemical information concerning the presence of molecules in a solution is usually achieved by measuring...
Thumbnail L. Adam, A. Kuhn Techniques de l'Ingénieur (2019)Ref:IN189 V1 Les molécules chirales sont d’un grand intérêt dans un certain nombre de domaines tels que la médecine, la biologie ou encore la chimie....
Thumbnail J.-P. Douliez, A. Perro, J.-P. Chapel, B. Goudeau and L. Béven Small 2018, 1803042 A template-free all-aqueous bulk preparation of robust hollow capsules having a gelatin shell from all-in-water...
Thumbnail G. Salinas, B. A. Frontana-Uribe, S. Reculusa, P. Garrigue, A. Kuhn Anal.Chem. 90 (2018) 11770 Highly ordered macroporous electrodes of the conducting polymer poly-3,4-ortho-xylendioxythiophene...
Thumbnail T. D. Le, L. Zhang, S. Reculusa, G.Vignoles, N. Mano, A. Kuhn, D. Lasseux ChemElectroChem 6 (2018) 173 This article reports on a procedure to predict the optimal thickness of cylindrical porous...
Thumbnail A. de Poulpiquet, B. Goudeau, P. Garrigue, N. Sojic, S. Arbault, T. Doneux, L. Bouffier. Chem. Sci. 2018, 9, 6622-6628. The coupling between electrochemistry and fluorescence confocal laser scanning...
Thumbnail V. Pirenne, G. Kurtay, S. Voci, L. Bouffier, N. Sojic, F. Robert, D. M. Bassani, Y. Landais. Org. Lett. 2018, 20 (15), 4521-4525. Eosin-Y (EY)-mediated alkylsulfonyl cyanation of olefins was shown...
Thumbnail I. Hernández Delgado, S. Pascal, C. Besnard, S. Voci, L. Bouffier, N. Sojic, J. Lacour. Chem. Eur. J. 2018, 24 (40), 10186-10195. A series of nine C‐functionalized cationic diazaoxa triangulene...
Thumbnail E. Suraniti, P. Merzeau, J. Roche, S. Gounel, A. G. Mark, P. Fischer, N. Mano, A. Kuhn Nature Comm. 2018, 9:3229 see also CNRS press release Chemical systems do not allow the coupling of energy from...
Thumbnail D. Kos, H. P. A. G. Astier, G. D. Martino, J. Mertens, H. Ohadi, D. De. Fazio, D. Yoon, Z. Zhao, A. Kuhn, A. C. Ferrari, C. J. B. Ford, J. J. Baumberg Small 14 (2018) 1801599 Nanoactuators are a key...
Thumbnail Ruigrok, H.J., Arnaud-Cormos D., Hurtier A., Poque-Haro E., Poulletier de Gannes F., Ruffié G., Bonnaudin F, Lagroye I., Sojic N., Arbault S., Lévêque P., Veyret B. and Percherancier Y. Radiation...
Thumbnail Girard F., Peret M., Dumont N., Badets V., Blanc S., Gazeli K., Noël C., Belmonte T., Marlin L., Cambus J.P., Simon G., Sojic N., Held B., Clément F. and Arbault S. Phys. Chem. Chem. Phys., 2018, 20,...
Thumbnail Lefrançois P., Goudeau B., Arbault S. Integrative Biology, 2018, in press Phospholipid Giant Unilamellar Vesicles (GUVs) are usually prepared by electroformation in water, that is in a...
Thumbnail E. Suraniti, A.G. Mark, J. Roche, H. Richter, A. Kuhn, P. Fischer, N. Mano L’Actualité Chimique 2018, 427-428,127-128 Une micro-source d’énergie intégrée permettrait à des implants biomédicaux...