Laboratoire d’analyse et d’architecture des systèmes
H.BERTRAND, A.ESTEVE, E.CAMPO, B.JAMMES
Valcap Valence Capteur, NEO, S4M, ISGE
Brevet : FR3049623 (A1), Février 2019 , N° 16412
L'invention concerne un procédé et un dispositif informatiques de surveillance continue d'un réseau de canalisations de circulation d'eaux résiduaires. Au moins une canalisation (12) est dotée d'au moins un capteur (14) d'écoulement. Un modèle nominal du capteur pour un état normal sans fuite est enregistré en l'absence de pluie sur une période de référence comprenant une plage nocturne entre T00:00 et T06:00 heure locale. Au moins un indicateur d'infiltration/exfiltration représentatif d'écoulements anormaux d'infiltration/exfiltration est élaboré par comparaison entre des signaux délivrés parle capteur d'écoulement et le modèle nominal dans la plage nocturne.
D.DHUNGANA, A.HEMERYCK, N.SARTORI, P.F.FAZZINI, F.CRISTIANO, S.PLISSARD
MPN, M3, EXT, LPCNO
Revue Scientifique : Nano Research, Décembre 2018 , N° 18560
A CMOS compatible process is presented in order to grow self-catalyzed InAs nanowires on silicon by molecular beam epitaxy. The crucial step of this process is a new in-situ surface preparation under hydrogen (gas or plasma) during the substrate degassing combined with an in-situ arsenic annealing prior to growth. Morphological and structural characterizations of the InAs nanowires are presented and growth mechanisms are discussed in detail. The major influence of surface termination is exposed both experimentally and theoretically using statistics on ensemble of nanowires and density functional theory (DFT) calculations. The differences observed between Molecular Beam Epitaxy (MBE) and Metal Organic Vapor Phase Epitaxy (MOVPE) growth of InAs nanowires can be explained by these different surfaces terminations. The transition between a vapor solid (VS) and a vapor liquid solid (VLS) growth mechanism is presented. Optimized growth conditions lead to very high aspect ratio nanowires (up to 50 nm in diameter and 3 micron in length) without passing the 410 °C thermal limit, which makes the whole process CMOS compatible. Overall, our results suggest a new method for surface preparation and a possible tuning of the growth mechanism using different surface terminations.
L.RECOULES, A.MIGAOU, X.DOLLAT, G.THOUAND, A.M.GUE, A.BOUKABACHE
MILE, I2C, Nantes
Revue Scientifique : Analytical and Bioanalytical Chemistry, Vol.410, N°4, pp.1189-1190, Novembre 2018 , N° 18378
Manifestation avec acte : NanoBio&Med ( ) 2018 du 20 novembre au 22 novembre 2018, Barcelone (Espagne), Novembre 2018 , N° 18558
P.TEERAPANICH, M.PUGNIERE, C.HENRIQUET, Y.L.LIN, A.NAILLON, P.JOSEPH, C.F.CHOU , T.LEICHLE
MEMS, IRCM, Academia Sinica, MILE
Revue Scientifique : Sensors and Actuators B: Chemical, N°274, pp.338-342, Novembre 2018 , N° 18465
We report a simple and cost-effective nanofluidic fluorescence microscopy platform with parallel kinetic assay capability for the determination of kinetic parameters in a single run. An on-chip microfluidic concentration diluter, or gradient generator, was integrated to a biofunctionalized nanofluidic chip, enabling simultaneous interrogation of multiple biomolecular interactions with a full titration series of analyte in a single experiment. We demonstrate that since the association and dissociation phases are induced by the on-chip gradient generator and a reverse buffer flow operation, complete kinetic sensorgrams for IgG/anti-IgG interactions can be achieved within 20 min on a single device, which is at least 10 times faster than traditional kinetic techniques. This method could contribute to low-cost, rapid and high-throughput drug-screening and clinical diagnostics.
R.MALBEC, J.CACHEUX, P.CORDELIER, T.LEICHLE, P.JOSEPH, A.BANCAUD
MICA, MEMS, CRCT-INSERM, MILE
Revue Scientifique : Micro and Nano Engineering, Vol.1, pp.25-32, Novembre 2018 , N° 18468
Genetic testing based on the analysis of circulating cell-free DNA (cfDNA) in body fluids, especially blood plasma, is raising interest for the management and follow-up of many diseases, including cancer. Because the concentration of cfDNA is low and its composition mostly degraded, this material can only be assayed with the most sensitive nucleic acid processing technologies. cfDNA analysis therefore constitutes a model target and a driving force for innovation in microfluidic biotechnologies. Here, we overview the main physico-chemical characteristics of cfDNA, and provide a critical review on the different methods for its processing out of blood samples. Then, we describe recent microfluidic developments for high sensitivity DNA analysis, evaluate their practical relevance for cfDNA analysis, and identify a few challenges for technologists in the near future.
L.J.HOLT, O.HALLATSCHEK, M.DELARUE
New York, Berkeley, MILE
Ouvrage (contribution) : Microfluidics in Cell Biology Part B: Microfluidics in Single Cells, N°ISBN 978-0-12-814282-0, Vol.147231, Octobre 2018, 215p. , N° 18315
Cells need to act upon the elastic extracellular matrix and against steric constraints when proliferating in a confined environment, leading to the build-up, at the population level, of a compressive, growth-induced, mechanical stress. Compressive mechanical stresses are ubiquitous to any cell population growing in a spatially-constrained environment, such as microbes or most solid tumors. They remain understudied, in particular in microbial populations, due to the lack of tools available to researchers. Here, we present various mechano-chemostats: microfluidic devices developed to study microbes under pressure. A mechano-chemostat permits researchers to control the intensity of growth-induced pressure through the control of cell confinement, while keeping cells in a defined chemical environment. These versatile devices enable the interrogation of physiological parameters influenced by mechanical compression at the single cell level and set a standard for the study of growth-induced compressive stress.
R.TICHAUER, G.FAVRE, S.CABANTOUS, G.LANDA, A.HEMERYCK, M.BRUT
M3, ICR, CRCT-INSERM
Revue Scientifique : Biophysical Journal, Vol.115, N°8, pp.1417-1430, Octobre 2018, doi 10.1016/j.bpj.2018.07.042 , N° 18306
Point mutations in p21ras are associated with ∼30% of human tumors by disrupting its GTP hydrolysis cycle, which is critical to its molecular switch function in cellular signaling pathways. In this work, we investigate the impact of Gln 61 substitutions in the structure of the p21N-ras active site and particularly focus on water reorganization around GTP, which appears to be crucial to evaluate favorable and unfavorable hydration sites for hydrolysis. The NRas-GTP complex is analyzed using a hybrid quantum mechanics/molecular mechanics approach, treating for the first time to our knowledge transient water molecules at the ab initio level and leading to results that account for the electrostatic coupling between the protein complex and the solvent. We show that for the wild-type protein, water molecules are found around the GTP γ-phosphate group, forming an arch extended from residues 12 to 35. Two density peaks are observed, supporting previous results that suggest the presence of two water molecules in the active site, one in the vicinity of residue 35 and a second one stabilized by hydrogen bonds formed with nitrogen backbone atoms of residues 12 and 60. The structural changes observed in NRas Gln 61 mutants result in the drastic delocalization of water molecules that we discuss. In mutants Q61H and Q61K, for which water distribution is overlocalized next to residue 60, the second density peak supports the hypothesis of a second water molecule. We also conclude that Gly 60 indirectly participates in GTP hydrolysis by correctly positioning transient water molecules in the protein complex and that Gln 61 has an indirect steric effect in stabilizing the preorganized catalytic site.
T.CALAIS, A.BANCAUD, A.ESTEVE, C.ROSSI
Revue Scientifique : ACS Applied Nano Materials, Vol.1, N°9, pp.4716-4725, Septembre 2018 , N° 18279
The association of a metallic fuel (usually aluminum) with an oxidizer (metal oxide or organic compound) creates an exothermic material that can be ignited with an external stimulus such as local heating or spark discharge. These materials with high energetic performances, called nanothermites, have been used to release temperature or pressure waves for civil or military applications (initiators, impact igniters, etc.). However, the energetic performances of these nanothermites are highly dependent on the nanoscale intimacy of the two components. The use of nanoparticles results in an increase of the energy release, but control of their assembly remains particularly challenging. In this work, we demonstrate that the use of DNA to self-organize Al or CuO nanoparticles greatly enhances the energy release of nanothermites by up to 240% compared to classically sonicated nanothermites in hexane, with the heat of reaction prior to Al melting reaching a value of 2.57 kJ·g–1. In particular, we report that the energetic performances can be tuned by controlling the ionic strength during the self-assembly process. These results are supported by ultrafine characterization of the nanocomposite microstructure based on high-resolution transmission electronic microscopy and energy-dispersive X-ray spectroscopy. Besides, we report the surprisingly good energetic performances of randomly mixed nanoparticles dispersed in water, nonetheless 40% lower than DNA-self-assembled nanocomposites. Altogether, our study not only proposes an easy and immediate process for nanocomposites synthesis but also opens the door for opportunities toward large-scale crystalline Al–CuO superlattices with high energetic performances.
O.LIOT, S.AKASH, P.BACCHIN, P.DURU, J.MORRIS, P.JOSEPH
MILE, LGC, IMFT, Levich Institute
Revue Scientifique : Scientific Reports, Vol.8, 12460p., Août 2018 , N° 17438
Blockage of pores by particles is found in numerous industrial and natural processes, including filtration and oil extraction. We present experimental results of filtration through a linear array of ten channels with one dimension which is sub-micron. These silicon-glass nanoslits serve as model pores, through which a dilute dispersion of Brownian polystyrene spheres flows. The clog growth rate at fixed differential pressure is shown to systematically increase with the number of saturated (entirely clogged) pores, indicating that there is an interaction or " cross-talk " between the pores. This observation is interpreted using a model proposed here, based on the concept that the residual permeability allows a clog to act as a filter. A clogged pore is thus the source of a local increase of particle concentration adjacent to the pore, which then diffuses towards other pores. This phenomenon, evidenced and modelled here in one dimension, should be at play in two-dimensional membranes.