« mars 2024 »
L M M J V S D
26 27 28 29 1 2 3
4 5 6 7 8 9 10
11 12 13 14 15 16 17
18 19 20 21 22 23 24
25 26 27 28 29 30 31
 
Tous les évènements de Physique à venir

Tous les évènements de Biologie / Chimie à venir

Tous les évènements à venir

Les évènements relevant de la Physique et de la Biologie / Chimie sont représentés en turquoise

ATTENTION SEMINAIRE ANNULE !!! Reporté au 10/05/2016 - Fast insulin amyloid aggregation at the air-liquid-solid triple interface

Mardi 26 avril 2016 14:00 - Duree : 1 heure
Lieu : Grenoble INP-Phelma, Laboratoire LMGP-2ème étage-salle de séminaire, 3 parvis Louis Néel - 38000 Grenoble

Orateur : Thibaut FRACHON (Eveon, LMGP, IMBM)

With the growing use of therapeutical proteins and the development of medical delivery devices, protein stability becomes a major concern in pharmaceutical industrial processes. Proteins can lose their native conformation by unfolding and reach a new free energy minimum by forming insoluble aggregates. Insulin is one example of such an aggregation-prone protein, which easily forms amyloid fibrils on hydrophobic surfaces under agitation. Within a device containing a protein solution, hydrophobic interfaces are found at the border between hydrophobic materials and liquid and between air and liquid. These different interfaces come into close proximity in protocols, frequently used in industry, involving intermittent wetting.

We designed a model experiment, where we observe by optical microscopy the formation of insulin amyloid fibers as a protein solution moves repetitively back and forth in a microfluidic channel. Thioflavin T fluorescence was used to monitor the formation of amyloid deposits and reflection interference contrast microscopy was used to monitor the morphology of the liquid film after receding. The growth of protein aggregates on the surface was characterized. We demonstrate that insulin fibers mainly form in regions of intermittent wetting, but not in regions exposed to hydrodynamic shear stress alone, remaining always wet. This clarifies the role of interfaces in insulin aggregation, showing that wall shear stress alone is insufficient to rapidly trigger amyloid fiber formation.

Contact : Michele.san-martin@grenoble-inp.fr

Discipline évènement : (Physique)
Entité organisatrice : (LMGP)
Nature évènement : (Séminaire)
Evènement répétitif : (Séminaire LMGP)
Site de l'évènement : Site Minatec

Prévenir un ami par email

Télécharger dans mon agenda

Cafés sciences de Grenoble | UdPPC de Grenoble | Sauvons Le Climat | Cafe des sciences de Vizille
Accueil du site | Secretariat | Espace privé | Suivre la vie du site RSS 2.0 : Tous les evenements Suivre la vie du site RSS 2.0 : Evenements de Physique Suivre la vie du site RSS 2.0 : Evenements de Biologie & Chimie