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4 results on '"Hélène Cayron"'

1. Siphon-Induced Droplet Break-Off for Enhanced Mixing on a Centrifugal Platform

Author

Robert Burger, David J Kinahan, Hélène Cayron, Nuno Reis, João Fonseca, and Jens Ducrée

Subjects
lab-on-a-chip, centrifugal microfluidics, lab-on-a-disc, mixing, siphon valves, Engineering machinery, tools, and implements, TA213-215, Technological innovations. Automation, HD45-45.2
Abstract

We present a powerful and compact batch-mode mixing and dilution technique for centrifugal microfluidic platforms. Siphon structures are designed to discretize continuous flows into a sequence of droplets of volumes as low as 100 nL. Using a passive, self-regulating 4-step mechanism, discrete volumes of two fluids are alternatingly issued into a common intermediate chamber. At its base, a capillary valve acts as a fluidic shift register; a single droplet is held in place while two or more droplets merge and pass through the capillary stop. These merged droplets are advectively mixed as they pass through the capillary valve and into the receiving chamber. Mixing is demonstrated for various combinations of liquids such as aqueous solutions as well as saline solutions and human plasma. The mixing quality is assessed on a quantitative scale by using a colorimetric method based on the mixing of potassium thiocyanate and iron(III) chloride, and in the case of human plasma using a spectroscopic method. For instance, volumes of 5 µL have been mixed in less than 20 s. Single-step dilutions up to 1:5 of plasma in a standard phosphate buffer solution are also demonstrated. This work describes the preliminary development of the mixing method which has since been integrated into a commercially available microfluidic cartridge.

Published
2019
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2. A novel 3D microdevice for the in vivo capture of cancer-associated cells

Author

Aline Cerf, David Bourrier, Charline Blatché, Hélène Cayron, Alejandro Kayum Jimenez Zenteno, Christophe Vieu, Bernard Malavaud, Aurore Estève, Sylvain Sanson, Denis Calise, Elise Bou, Équipe Ingénierie pour les sciences du vivant (LAAS-ELIA), Laboratoire d'analyse et d'architecture des systèmes (LAAS), Université Toulouse 1 Capitole (UT1)-Institut National des Sciences Appliquées - Toulouse (INSA Toulouse), Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Université Toulouse - Jean Jaurès (UT2J)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut National Polytechnique (Toulouse) (Toulouse INP), Université Fédérale Toulouse Midi-Pyrénées-Université Toulouse 1 Capitole (UT1)-Institut National des Sciences Appliquées - Toulouse (INSA Toulouse), Université Fédérale Toulouse Midi-Pyrénées, Service Techniques et Équipements Appliqués à la Microélectronique (LAAS-TEAM), CHU Rangueil, Toulouse, France., Institut National de la Santé et de la Recherche Médicale (INSERM), Service Instrumentation Conception Caractérisation (LAAS-I2C), Institut Universitaire du Cancer de Toulouse - Oncopole (IUCT Oncopole - UMR 1037), Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-CHU Toulouse [Toulouse]-Institut National de la Santé et de la Recherche Médicale (INSERM), Institut Universitaire du Cancer de Toulouse, Département de microchirurgie de Rangueil, ANR-15-CE19-0020,NODENS,Nouveaux Objets triDimensionnels Embarqués pour la Nano-analyse du Sang(2015), Université Toulouse Capitole (UT Capitole), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut National des Sciences Appliquées - Toulouse (INSA Toulouse), Institut National des Sciences Appliquées (INSA)-Université de Toulouse (UT)-Institut National des Sciences Appliquées (INSA)-Université Toulouse - Jean Jaurès (UT2J), Université de Toulouse (UT)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Centre National de la Recherche Scientifique (CNRS)-Institut National Polytechnique (Toulouse) (Toulouse INP), Université de Toulouse (UT)-Université Toulouse Capitole (UT Capitole), Université de Toulouse (UT), Centre Hospitalier Universitaire de Toulouse (CHU Toulouse), Université de Toulouse (UT)-Université de Toulouse (UT)-Centre Hospitalier Universitaire de Toulouse (CHU Toulouse)-Institut National de la Santé et de la Recherche Médicale (INSERM), Université Toulouse - Jean Jaurès (UT2J)-Université Toulouse 1 Capitole (UT1), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Institut National des Sciences Appliquées - Toulouse (INSA Toulouse), Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Institut National Polytechnique (Toulouse) (Toulouse INP), Université Fédérale Toulouse Midi-Pyrénées-Université Toulouse - Jean Jaurès (UT2J)-Université Toulouse 1 Capitole (UT1), Hôpital de Rangueil, and CHU Toulouse [Toulouse]

Subjects
[SDV.BIO]Life Sciences [q-bio]/Biotechnology, Venous circulation, [SDV.CAN]Life Sciences [q-bio]/Cancer, [SDV.BC.BC]Life Sciences [q-bio]/Cellular Biology/Subcellular Processes [q-bio.SC], 03 medical and health sciences, 0302 clinical medicine, Circulating tumor cell, Animal model, Electroforming, In vivo, Medicine, Liquid biopsy, [SPI.NANO]Engineering Sciences [physics]/Micro and nanotechnologies/Microelectronics, 030304 developmental biology, 0303 health sciences, business.industry, Cancer, Direct Laser Writing, medicine.disease, Clinical routine, 030220 oncology & carcinogenesis, Cancer cell, Cancer research, business, Circulating Tumor Cells
Abstract

International audience; Circulating tumour cells (CTCs) correlate by their number to the lethal potential of the tumour and can be characterized in terms of molecular properties. The repeated isolation of living CTCs has now appeared as an unavoidable step towards their use as biomarkers in clinical routine. We introduce a 3D stealthy microdevice adapted to the in vivo capture of CTCs in the venous blood flow, on the basis of their physical characteristics, size and rigidity. Embedded in a fluidic bench mimicking an artificial arm vein, it readily captured human prostate cancer cells spiked into donor blood down to a concentration of 1,000 cells/ml. The isolation of cancer cells in venous circulation was validated in an animal model in vivo. These results open new avenues to the characterization of CTCs in prognosis, personalization of treatments and follow‐up, not only as a research tool, but also for repeated monitoring in clinical practice.

Published
2019
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3. Controlled deposition and multi-layer architecturing of single biomolecules using automated directed capillary assembly and nano-contact printing processes

Author

Vincent Paveau, Jean Christophe Cau, Christophe Vieu, Benjamin Berteloite, Hélène Cayron, Aline Cerf, Équipe NanoBioSystèmes (LAAS-NBS), Laboratoire d'analyse et d'architecture des systèmes (LAAS), Université Toulouse Capitole (UT Capitole), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut National des Sciences Appliquées - Toulouse (INSA Toulouse), Institut National des Sciences Appliquées (INSA)-Université de Toulouse (UT)-Institut National des Sciences Appliquées (INSA)-Université Toulouse - Jean Jaurès (UT2J), Université de Toulouse (UT)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Centre National de la Recherche Scientifique (CNRS)-Institut National Polytechnique (Toulouse) (Toulouse INP), Université de Toulouse (UT)-Université Toulouse Capitole (UT Capitole), Université de Toulouse (UT), Innopsys [Carbonne], Université Toulouse - Jean Jaurès (UT2J)-Université Toulouse 1 Capitole (UT1), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Institut National des Sciences Appliquées - Toulouse (INSA Toulouse), Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Institut National Polytechnique (Toulouse) (Toulouse INP), Université Fédérale Toulouse Midi-Pyrénées-Université Toulouse - Jean Jaurès (UT2J)-Université Toulouse 1 Capitole (UT1), and Université Fédérale Toulouse Midi-Pyrénées

Subjects
Materials science, Fabrication, Capillary action, Nanotechnology, 02 engineering and technology, [SPI.MAT]Engineering Sciences [physics]/Materials, 03 medical and health sciences, Nano, Deposition (phase transition), Electrical and Electronic Engineering, [SPI.NANO]Engineering Sciences [physics]/Micro and nanotechnologies/Microelectronics, 030304 developmental biology, chemistry.chemical_classification, [PHYS]Physics [physics], 0303 health sciences, Biomolecule, Process (computing), 021001 nanoscience & nanotechnology, Condensed Matter Physics, Atomic and Molecular Physics, and Optics, Surfaces, Coatings and Films, Electronic, Optical and Magnetic Materials, chemistry, Meniscus, 0210 nano-technology, Contact print
Abstract

International audience; Up to date, a large amount of research studies have been carried out to manipulate and arrange biomo-lecules at the single molecule scale using capillary forces. However, many of these techniques remain in the fundamental research field, their industrial transfer being restricted by poor repeatability and user-dependent processes. We present an automated process for the controlled and large scale deposition of single biomolecules, relying on the use of directed capillary assembly and nano-contact printing processes. The adjustment and control of physical parameters allow for single molecule deposition, and the use of an automate operating arm ensures high reproducibility and freedom in the assembly architectures to create. This methodology was used to assemble DNA molecules and actin filaments (or F-actin), evidencing two distinct assembly mechanisms. In the first one we use capillary forces to trap and elongate preformed 1D structures such as DNA molecules. In the second case, fluid flows created upon evaporation and local pinning of the meniscus favor the F-actin polymerization through continuous supply of monomers. In this way, we introduce a new concept of using capillary assembly as a construction tool to assemble 1D nano-structures. Additionally, by sequentially aligning and printing multiple single molecule assemblies, large-scale multi-layer architectures of single molecules were also obtained. The large-scale capabilities and reliability of our fabrication process render sophisticated single molecule biophysical measurements possible with systematic analysis over a large population for statistical relevance.

Published
2015
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4. 3D-microdevice for the in vivo capture of cancer-associated circulating cells

Author

Bernard Malavaud, Sylvain Sanson, Hélène Cayron, Alejandro Kayum Jimenez Zenteno, Aurore Esteve, Aline Cerf, and Christophe Vieu

Subjects
Cancer Research, Pathology, medicine.medical_specialty, Cell adhesion molecule, business.industry, Cancer, medicine.disease, In vitro, Circulating tumor cell, Oncology, In vivo, Blood circulation, Cancer cell, medicine, Overall survival, Cancer research, business
Abstract

e579 Background: Circulating tumor cells (CTCs) are cancer cells that have detached from a tumor and have entered into the blood circulation at a very low concentration (D. Shook, Mech. Dev., Nov 2003). CTCs have a strong prognostic value, as their number has been correlated to overall survival in different metastatic cancers (J. S. de Bono, Clin. Cancer Res., Oct 2008). Considering the rareness of CTCs in blood, capturing them in vitro is very challenging. CTCs being mainly larger and less deformable than most of blood cells, ISET was the first system exploiting their physical traits using a filtration membrane to enrich 10mL blood samples (G. Vona, Am. J. Pathol., Jan 2000). However, placing the trapping system directly within the bloodstream would increase the amount of blood screened and ensure no sampling bias. To our knowledge, the only system developed for in vivo capture of CTCs relies on an immunologic detection targeting CTCs with specific epithelial-cell adhesion molecules (N. Saucedo-Zeni, Int. J. Oncol., Oct 2012). The major drawback of this technique is the selection bias induced, given the strong heterogeneity of antigen expression profiles in CTC population as confirmed by several studies. Methods: Our device combines the advantages of in vivo capture and physical trapping of CTCs. A polymeric 3D net-like microdevice is fabricated using a Direct Laser Writing technique (Nanoscribe) and integrated onto a Nitinol guidewire to be introduced into the basilic vein through a routine 20G catheter. To optimize the design, we conducted simulation studies and in vitro assays using a fluidic platform reproducing in vivo conditions. Results: We succeeded in capturing PC3 human prostate cancer cells from 20 mL healthy donor blood spiked with 1,000 PC3 cells in 2 minutes, demonstrating the capability to capture CTCs in conditions close to those found in vivo, in terms of pressure and flow rate and without any additional treatment or dilution of the blood. Conclusions: This device could facilitate treatment personalization and follow-up. Its versatility should render it transposable to the capture of single or clustered CTCs, derived from all types of cancer and, by extension, to other circulating cellular and molecular biomarkers.

Published
2017
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