Accueil >
Production scientifique
Physique de systèmes biologiques
(18) Production(s) de l'année 2019
|
|
Mucus Microrheology Measured on Human Bronchial Epithelium Culture
Auteur(s): Jory M., Bellouma Karim, Blanc C., Casanellas Vilageliu L., Petit Aurelie, Reynaud Paul, Vernisse Charlotte, Vachier Isabelle, Bourdin Arnaud, Massiera G.
(Article) Publié:
Frontiers In Physics, vol. 7 p.19 (2019)
Texte intégral en Openaccess :
Ref HAL: hal-02025486_v1
DOI: 10.3389/fphy.2019.00019
WoS: WOS:000459130800002
Exporter : BibTex | endNote
1 Citation
Résumé: We describe an original method to measure mucus microrheology on human bronchial epithelium culture using optical tweezers. We probed rheology on the whole thickness of mucus above the epithelium and showed that mucus gradually varies in rheological response, from an elastic behavior close to the epithelium to a viscous one far away. Microrheology was also performed on mucus collected on the culture, on ex vivo mucus collected by bronchoscopy, and on another epithelium model. Differences are discussed and are related to mucus heterogeneity, adhesiveness and collection method.
|
|
|
pH-mediated control over the mesostructure of ordered mesoporous materials templated by polyion complex micelles
Auteur(s): Molina Emilie, Mathonnat M., Richard Jason, Lacroix-Desmazes Patrick, In M., Dieudonne-George P., Cacciaguerra Thomas, Gerardin Corine, Marcotte Nathalie
(Article) Publié:
Beilstein Journal Of Nanotechnology, vol. 10 p.144-156 (2019)
Texte intégral en Openaccess :
Ref HAL: hal-01992289_v1
DOI: 10.3762/bjnano.10.14
WoS: 000455446300001
Exporter : BibTex | endNote
2 Citations
Résumé: Ordered mesoporous silica materials were prepared under different pH conditions by using a silicon alkoxide as a silica source and polyion complex (PIC) micelles as the structure-directing agents. PIC micelles were formed by complexation between a weak poly-acid-containing double-hydrophilic block copolymer, poly(ethylene oxide)-b-poly(acrylic acid) (PEO-b-PAA), and a weak poly-base, oligochitosan-type polyamine. As both the micellization process and the rate of silica condensation are highly dependent on pH, the properties of silica mesostructures can be modulated by changing the pH of the reaction medium. Varying the materials synthesis pH from 4.5 to 7.9 led to 2D-hexagonal, wormlike or lamellar mesostructures, with a varying degree of order. The chemical composition of the as-synthesized hybrid organic/inorganic materials was also found to vary with pH. The structure variations were discussed based on the extent of electrostatic complexing bonds between acrylate and amino functions and on the silica condensation rate as a function of pH.
|
|
|
Probing shear-induced rearrangements in Fourier space. I. Dynamic light scattering
Auteur(s): Aime S., Cipelletti L.
(Article) Publié:
Soft Matter, vol. 15 p.200-212 (2019)
Texte intégral en Openaccess :
Ref HAL: hal-01982836_v1
DOI: 10.1039/c8sm01563e
WoS: WOS:000454947400016
Exporter : BibTex | endNote
5 Citations
Résumé: Understanding the microscopic origin of the rheological behavior of soft matter is a long-lastingendeavour. While early efforts concentrated mainly on the relationship between rheology and structure,current research focuses on the role of microscopic dynamics. We present in two companion papers athorough discussion of how Fourier space-based methods may be coupled to rheology to shed light onthe relationship between the microscopic dynamics and the mechanical response of soft systems. In thisfirst companion paper, we report a theoretical, numerical and experimental investigation of dynamiclight scattering coupled to rheology. While in ideal solids and simple viscous fluids the displacement fieldunder a shear deformation is purely affine, additional non-affine displacements arise in many situationsof great interest, for example in elastically heterogeneous materials or due to plastic rearrangements.We show how affine and non-affine displacements can be separately resolved by dynamic lightscattering, and discuss in detail the effect of several non-idealities in typical experiments.
|
|
|
Probing shear-induced rearrangements in Fourier space. II. Differential dynamic microscopy
Auteur(s): Aime S., Cipelletti L.
(Article) Publié:
Soft Matter, vol. 15 p.213-226 (2019)
Texte intégral en Openaccess :
Ref HAL: hal-01982835_v1
DOI: 10.1039/c8sm01564c
WoS: WOS:000454947400017
Exporter : BibTex | endNote
3 Citations
Résumé: We discuss in two companion papers how Fourier-space measurements may be coupled to rheologicaltests in order to elucidate the relationship between mechanical properties and microscopic dynamics insoft matter. In this second companion paper, we focus on Differential Dynamic Microscopy (DDM)under shear. We highlight the analogies and the differences with dynamic light scattering coupled torheology, providing a theoretical approach and practical guidelines to separate the contributions toDDM arising from the affine and the non-affine part of the microscopic displacement field. We showthat in DDM under shear the coherence of the illuminating source plays a key role, determining theeffective sample thickness that is probed. Our theoretical analysis is validated by experiments on 2Dsamples and 3D gels.
|