Développement d'un capteur colorimétrique innovant pour la détection directe du phénol dans l'air et dans l'eau

International audienc

Développement de matériaux poreux hybrides innovants pour l'analyse glycomique

International audienceL'analyse glycomique consiste à établir le profil des oligosaccharides présents sur l'ensemble des glycoprotéines d'un fluide biologique d'intérêt (ex : plasma) . Cependant, la préparation des échantillons implique de nombreuses étapes souvent manuelles, très chronophages et peu compatibles avec l'analyse à haut débit des échantillons. Les matériaux préparés selon le procédé sol-gel, par leur grande adaptabilité en terme de porosité et de propriétés physico-chimiques, ont montré qu'ils pouvaient être utilisés pour une grande variété d'applications tels que la détection (capteurs) ou la capture de molécules d'intérêt , notamment dans le domaine biomédical. Dans cette optique, nous développons des matériaux à porosité bimodale pour faciliter et accélérer la préparation des échantillons dédiés à l'analyse glycomique. Les premiers résultats obtenus seront présentés, en particulier le procédé de synthèse, les modulations possibles des matériaux (microstructure et porosité) ainsi que la caractérisation de leurs propriétés texturales et microstructurales. Enfin, quelques résultats prometteurs obtenus à l'aide de ces matériaux sur des échantillons biologiquement pertinents seront également présentés

Shelf-life e qualit\ue0 microbiologica di pizze refrigerate e confezionate in atmosfera modificata

The microbiological quality and the shelf-life of pizza, packaged in modified atmosphere and stored at 2\ub0C were evalued. By accelerated shelf-life test (ASLT) and by Q10 factor obtained was possible to identify the time of the shelf-life of the pizzas. The growth of C. botulinum type E nontoxic and of C. sporogenes artificially added was investigated. The pizzas have an high standard of microbial quality, clostridia did not grow even when pizza was stored at 12\ub0C. The Q10 factor also permitted to define the shelf-life of the pizzas at the moment of their production and the value was similar to that obtained by microbial analysis

Innovative colorimetric sensors for the selective detection of monochloramine in air and in water

International audienceAbstract The development of a new disposable chemical sensor for the direct and selective detection of monochloramine, NH2Cl, a toxic pollutant present in both water and atmosphere of indoor swimming pools, is described. This innovative chemical and colorimetric sensor is based on the use of nanoporous matrices doped with probe-molecules, which act as sponges to trap the targeted pollutant and turn from transparent to dark blue. The calibration for gaseous NH2Cl was carried out with concentrations ranging from 60 to 250 ppb at room temperature and in humid atmosphere. In water the detection limit of NH2Cl is 0.01 mg/L. This method, which is selective and easy-to-use, could favorably replace the current method of detection of free and combined chlorine used in swimming pools

Imagerie de bio-puces multiplexes dans l'ultraviolet pour l'identification de menaces biologiques

WorkshopNational audienc

A microsystem for air quality measurement in future housings

International audienceNowadays, about half of humanity is housed in cities, a number expected to rise up to more than 2/3 by 2050 . Whether such a prediction is accurate is not relevant, we already experience the major issue that breathing a reasonably pure indoor air is becoming. Analytical chemistry has thus tremendous challenges ahead, among which the ability to design sensing elements for continuous air quality monitoring in closed environments. Functional materials with specific optimized properties are a growing part of modern chemistry and such materials may lead to disruptive solution in the field of analytical chemistry. For instance, hybrid porous materials prepared by the Sol-Gel process may be turned into functional sensing materials through careful formulation and process control . Incorporating such materials into microsystems is one promising way to new sensing approaches but their integration for sensing purposes into microsystems is far from being straightforward, which probably explains that it has not been reported yet. We have developed a microsystem based on an innovative microfluidic design and functional materials integrations that allows for gas detection and is compatible with continuous air quality measurements. First, we will describe the specificity of its design concerning micro-reactors fabrication and sensing capability. The preparation of the microfluidic device from micro-milled brass molds, and the method for fast and neat preparation of hundreds of individual micro-reactors will be reviewed. Then, the keys steps necessary to integrate functional materials into this device, such as the control of gelation will be explained. Special emphasis will be put on the interesting materials behavior within the microsystem. Finally, we will demonstrate the ability of our microsystem to perform quantitative optical detection of one of the main indoor air pollutants: formaldehyde . Based on air quality regulation, we will discuss the possibility of using such air quality monitoring microsystems in housings

Colorimetric sensors for the detection of monochloramine and nitrogen trichloride at ppb level in swimming pools.

International audienc

Innovative porous materials for enhanced glycomic analysis

International audienceHierarchical porosity sol-gel monoliths (HPMs) are of increasing interest for a wide variety of applications due to their outstanding microstructural (homogenous) and textural properties (high porosity and specific surface area) [1]. The high flow rate and low-pressure resultant compared to conventional materials, makes them suited for extraction and enrichment of analytes of interest in analytical techniques (HPLC, SPE, etc.) [2–4]. However, pure inorganic materials have rarely been considered for relevant applications in various omics fields such as metabolomics or proteomics [5].In the context, we report on: (i) a pure silica HPM based on a finely tuned bimodal porosity thoroughly controlled, (ii) coupled to a new way to a miniaturize shaping (iii) and its use as an innovative tool for sample preparation prior to glycan analysis by mass spectrometry, as a new source of disease biomarkers (glycomics analysis). The monolith synthesis will be presented with a special emphasize on its robustness and on the modulations of the bimodal porosity obtained ([0.1–5] μm and [1-25] nm). Beside microstructural and textural properties measurements (SEM, Hg porosimetry, etc.), the transport of small molecules through mesoporous network were evaluated by TEM tomography. Finally, the material was processed in different shapes and size (50 μm – 4 mm in diameter) demonstrating a high flexibility of our approach to produce devices dedicated to a biological analysis. The use of HPM for the analysis of both free and protein-bound oligosaccharides present in precious samples (human blood and milk) and their detection by MALDI-TOF mass spectrometry will be presented as a proof of concept. Optimized experimental conditions, as well as material textures and shapes, enabled straightforward and time-efficient purification and MS- based glycomics analysis using minute quantities (few μl) of solvents but above all of complex human biofluids, thus outperforming common laboratory protocols