Laboratoire d’analyse et d’architecture des systèmes
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
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.
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.
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.
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.
C.MAGNANI, C.MONTIS, G.MANGIAPIA, A.F.MINGOTAUD, C.MINGOTAUD, C.ROUX, P.JOSEPH, D.BERTI, B.LONETTI
IMRCP, UNIFI, Forschungszentrum, MILE
Revue Scientifique : Colloids and Surfaces B: Biointerfaces, Vol.168, pp.18-28, Août 2018 , N° 18144
In recent years, there has been a growing interest in the formation of copolymers-lipids hybrid self-assemblies, which allow combining and improving the main features of pure lipids-based and copolymer-based systems known for their potential applications in the biomedical field. In this contribution we investigate the self-assembly behavior of dipalmitoylphosphatidylcholine (DPPC) mixed with poly(butadiene-b-ethyleneoxide) (PBD-PEO), both at the micro- and at the nano-length scale. Epifluorescence microscopy and Laser Scanning Confocal microscopy are employed to characterize the morphology of micron-sized hybrid vesicles. The presence of fluid-like inhomogeneities in their membrane has been evidenced in all the investigated range of compositions. Furthermore, a microfluidic set-up characterizes the mechanical properties of the prepared assemblies by measuring their deformation upon flow: hybrids with low lipid content behave like pure polymer vesicles, whereas objects mainly composed of lipids show more variability from one vesicle to the other. Finally, the structure of the nanosized assemblies is characterized through a combination of Dynamic Light Scattering, Small Angle Neutron Scattering and Transmission Electron Microscopy. A vesicles-to-wormlike transition has been evidenced due to the intimate mixing of DPPC and PBD-PEO at the nanoscale. Combining experimental results at the micron and at the nanoscale improves the fundamental understanding on the phase behavior of copolymer-lipid hybrid assemblies, which is a necessary prerequisite to tailor efficient copolymer-lipid hybrid devices.
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.
Manifestation avec acte : International workshop on new micro technology and translational approaches for organ regeneration and cancer therapies ( ) 2018 du 26 juin au 27 juin 2018, Tokyo (Japon), Juin 2018 , N° 18559
B.CHAMI, M.SOCOL, M.MANGHI, A.BANCAUD
MILE, IRSAMC, Toulouse
Revue Scientifique : Soft Matter, Vol.14, N°24, pp.5069-5079, Juin 2018 , N° 18344
DNA separation and analysis have advanced over recent years, benefiting from microfluidic systems that reduce sample volumes and analysis costs, essential for sequencing and disease identification in body fluids. We recently developed the μLAS technology that enables the separation, concentration, and analysis of nucleic acids with high sensitivity. The technology combines a hydrodynamic flow actuation and an opposite electrophoretic force in viscoelastic polymer solutions. Combining hydrodynamics first principles and statistical mechanics, we provide, in this paper, a quantitative model of DNA transport capable of predicting device performance with the exclusive use of one adjustable parameter associated with the amplitude of transverse viscoelastic forces. The model proves to be in remarkable agreement with DNA separation experiments, and allows us to define optimal conditions that result in a maximal resolution length of 7 bp. We finally discuss the usefulness of our model for separation technologies involving viscoelastic liquids.