GRAYSCALE LITHOGRAPHY TO FABRICATE VARYING-DEPTH NANOCHANNELS IN A SINGLE STEP

International audienceWe report a new, fast and versatile method to fabricate nanochannels with non-uniform depth in a single step, in the range 50-500nm. The process is based on maskless laser lithography to structure a photosensitive resist (PR). The lateral dimension can be as small as 2µm. Functional nanofluidic chips with slopes, steps, and pore networks mimicking a nanoporous medium were fabricated and tested

Quasi-static drainage in a network of nanoslits of non-uniform depth designed by grayscale laser lithography

International audienceA method is reported to fabricate silicon-glass nanofluidic chips with non-uniform channel depths in the range 20-500 nm and micrometer resolution in width. The process is based on grayscale laser lithography to structure photoresist in 2.5 dimensions in a single step, followed by a reactive ion etching to transfer the resist depth profile into silicon. It can be easily integrated in a complete process flow chart. The method is used to fabricate a network of interconnected slits of non-uniform depth, a geometry mimicking a nanoporous medium. The network is then used to perform a pressure step controlled drainage experiment, i.e. the immiscible displacement of a wetting fluid (liquid water) by a non-wetting one (nitrogen). The drainage patterns are analyzed by comparison with simulations based on the invasion percolation algorithm. The results indicate that slow drainage in the considered nanofluidic system well corresponds to the classical capillary fingering regime

OPA1 gene therapy prevents retinal ganglion cell loss in a Dominant Optic Atrophy mouse model

Abstract Dominant optic atrophy (DOA) is a rare progressive and irreversible blinding disease which is one of the most frequent forms of hereditary optic neuropathy. DOA is mainly caused by dominant mutation in the OPA1 gene encoding a large mitochondrial GTPase with crucial roles in membrane dynamics and cell survival. Hereditary optic neuropathies are commonly characterized by the degeneration of retinal ganglion cells, leading to the optic nerve atrophy and the progressive loss of visual acuity. Up to now, despite increasing advances in the understanding of the pathological mechanisms, DOA remains intractable. Here, we tested the efficiency of gene therapy on a genetically-modified mouse model reproducing DOA vision loss. We performed intravitreal injections of an Adeno-Associated Virus carrying the human OPA1 cDNA under the control of the cytomegalovirus promotor. Our results provide the first evidence that gene therapy is efficient on a mouse model of DOA as the wild-type OPA1 expression is able to alleviate the OPA1-induced retinal ganglion cell degeneration, the hallmark of the disease. These results displayed encouraging effects of gene therapy for Dominant Optic Atrophy, fostering future investigations aiming at clinical trials in patients

Bilan des activités de la plateforme de micro et nano technologies du LAAS-CNRS

National audienceLa plateforme de micro et nanotechnologies du LAAS fait partie du réseau RENATECH. Elle offre aux domaines sensibles aux contaminations environnementales une concentration particulaire maîtrisée, une régulation de la température, de l'humidité, et de la lumière pour certaines opérations sensibles aux rayonnements ultraviolets au sein de la salle de 1600 m² en classes 100 et 10 000. Les équipements permettent l’élaboration, la mise en forme, le traitement de matériaux pour le prototypage de composants microélectroniques, optoélectroniques, micro et nano systèmes.La gestion et le développement de l’infrastructure, des équipements et procédés ; le soutien aux projets de recherche sont assurés par le service TEAM. Ces moyens humains et technologiques assurent le soutien des actions de recherche internes au LAAS, mais aussi l'accueil de demandes externes dans le cadre du réseau Renatech.Annuellement l’activité du service est examinée par une commission (ComTEAM), présidée par le Directeur du laboratoire.Ce document réalisé annuellement fait le bilan des activités 2016 et se projette sur des actions à conduire en 2017 dans les différentes zones gérées par le service TEAM