AF4-UHPLC: Two-dimensional separation of macromolecules in four white wines from South-Western France.

Proteins in wines contribute to "protein haze," which, while not affecting health or taste, can detract from the visual appeal of wines to consumers. To mitigate this issue, winemakers commonly use fining agents such as bentonite, despite the high costs involved. To overcome these challenges, numerous studies employ various analytical methods to better understand the behaviour of proteins.

High and low pathogenicity avian influenza virus discrimination and prediction based on volatile organic compounds signature by SIFT-MS: a proof-of-concept study.

High and low pathogenicity avian influenza viruses (HPAIV, LPAIV) are the primary causes of poultry diseases worldwide. HPAIV and LPAIV constitute a major threat to the global poultry industry. Therefore, early detection and well-adapted surveillance strategies are of the utmost importance to control the spread of these viruses.

Ozonized 2-hydroxypropyl-β-cyclodextrins as novel materials with oxidative and bactericidal properties.

Ozonized (2-Hydroxypropyl)-β-cyclodextrins (Oz-HPbCDs) were produced by direct gas/solid reaction between gaseous ozone (O) and solid HPbCD. The solid materials obtained were first characterized using physical and chemical methods and compared to the initial HPbCD. The main process parameters of the synthesis were studied independently to assess their effect on the oxidizing power of Oz-HPbCDs.

Study of the relationship between red wine colloidal fraction and astringency by asymmetrical flow field-flow fractionation coupled with multi-detection.

Macromolecules including condensed tannins and polysaccharides impact wine taste and especially astringency. Asymmetrical Flow-Field-Flow-Fractionation (AF4) coupled to UV detection (UV), multi-angle light scattering (MALS) and refractive index detection (dRI) has been proposed to separate red wine colloids. The present work aimed at relating AF4-mutidetection profiles with red wine astringency.

Ozonation of three different fungal conidia associated with apple disease: Importance of spore surface and membrane phospholipid oxidation.

Although ozone (O) is a well-known bactericide and fungicide, the required dose of ozone can depend significantly on the targeted pathogens. The present research evaluates the variation in sensibility to ozone of three fungal species from a single fungal group. The three fungal species selected, , , and , belong to the Ascomycota group and attack apples.

Prediction and detection of human epileptic seizures based on SIFT-MS chemometric data.

Although epilepsy is considered a public health issue, the burden imposed by the unpredictability of seizures is mainly borne by the patients. Predicting seizures based on electroencephalography has had mixed success, and the idiosyncratic character of epilepsy makes a single method of detection or prediction for all patients almost impossible. To address this problem, we demonstrate herein that epileptic seizures can not only be detected by global chemometric analysis of data from selected ion flow tube mass spectrometry but also that a simple mathematical model makes it possible to predict these seizures (by up to 4 h 37 min in advance with 92% and 75% of samples correctly classified in training and leave-one-out-cross-validation, respectively).

Fractionation and characterization of polyphenolic compounds and macromolecules in red wine by asymmetrical flow field-flow fractionation.

Red wine is a complex matrix containing macromolecules such as condensed tannins and polysaccharides. Wine macromolecular components and their interactions have been reported to impact taste properties such as astringency but the colloidal systems formed in wine are not well known. A key prerequisite to characterize these systems is the ability to work under analytical conditions as close as possible to the colloid environment, preserving the sample structure and limiting the denaturation of macromolecular complexes.

Ozone Quantification by Selected Ion Flow Tube Mass Spectrometry: Influence of Humidity and Manufacturing Gas of Ozone Generator.

The quantification of ozone by SIFT-MS was investigated in conditions suitable with an industrial emission context (high ozone demand, dry air/oxygen as the manufacturing gas of the ozone generator, and high humidity levels beyond saturation at room conditions). Ozone reacts with four negative precursor ions available in the SIFT-MS device (NO, O, HO, and O), each precursor ion having its specific domain of linearity. For a high ozone concentration range, only NO and O have resulted in a linear behavior (between 1 and 100 ppmv of O for NO, between 1 and 50 ppmv of O for O).

Aldehydes gas ozonation monitoring: Interest of SIFT/MS versus GC/FID.

Two analytical techniques - online Gas Chromatography coupled with Flame Ionization Detector (often used method for VOCs monitoring) versus Selected Ion Flow Tube coupled with Mass Spectrometry (a more recent technique based on direct mass spectrometry) - were compared in association to an ozone-based gas treatment. Selecting aldehydes as the representative VOCs, their concentrations were monitored during ozonation experiments by both techniques in parallel. Contradictory results were obtained in the presence of ozone.

Physicochemical characterization and study of molar mass of industrial gelatins by AsFlFFF-UV/MALS and chemometric approach.

Industrial gelatins have different physicochemical properties that mainly depend of the raw materials origin and the extraction conditions. These properties are closely related to the molar mass distribution of these gelatins. Several methods exist to characterize molar mass distribution of polymer, including the Asymmetrical Flow Field Flow Fractionation method.

Modulating analytical characteristics of thermovinified Carignan musts and the volatile composition of the resulting wines through the heating temperature.

The impact of two temperature levels (50 °C and 75 °C) and heating times (30 min and 3 h) on the composition of thermovinified musts and wines from Carignan was investigated at the laboratory scale in 2014 and 2015. The heating temperature had a significant impact on the extraction of amino acids and a probable thermal degradation of anthocyanins was noted at 75 °C. In 2014, musts from grapes that underwent a heat treatment at 50 °C for 3 h had a similar level of phenolic compounds as those treated at 75 °C for 30 min.

Characterization of Non-Derivatized Cellulose Samples by Size Exclusion Chromatography in Tetrabutylammonium Fluoride/Dimethylsulfoxide (TBAF/DMSO).

This paper deals with the use of tetrabutylammonium fluoride/dimethylsulfoxide (TBAF/DMSO) to characterize the molar mass distribution of non-derivatized cellulosic samples by size exclusion chromatography (SEC). Different cellulose samples with various average degree of polymerization (DP) were first solubilized in this solvent system, with increasing TBAF rates, and then analyzed by SEC coupled to a refractive index detector (RID), using DMSO as mobile phase. The Molar Masses (MM) obtained by conventional calibration were then discussed and compared with suppliers' data and MM determined by viscosimetry measurements.

Frit inlet field-flow fractionation techniques for the characterization of polyion complex self-assemblies.

Polymer self-assemblies joining oppositely charged chains, known as polyion complexes (PICs), have been formed using poly(ethyleneoxide - b - acrylic acid)/poly(l-lysine), poly(ethyleneoxide-b-acrylic acid)/dendrigraft poly(l-lysine) and poly[(3-acrylamidopropyl) trimethylammonium chloride - b - N - isopropyl acrylamide]/poly(acrylic acid). The self-assemblies have been first characterized in batch by Dynamic Light Scattering. In a second step, their analysis by Flow Field-Flow Fractionation techniques (FlFFF) was examined.

Drug Release by Direct Jump from Poly(ethylene-glycol-b-ε-caprolactone) Nano-Vector to Cell Membrane.

Drug delivery by nanovectors involves numerous processes, one of the most important being its release from the carrier. This point still remains unclear. The current work focuses on this point using poly(ethyleneglycol-b-ε-caprolactone) micelles containing either pheophorbide-a (Pheo-a) as a fluorescent probe and a phototoxic agent or fluorescent copolymers.

Structural modifications of cellulose samples after dissolution into various solvent systems.

This work deals with the modifications resulting from the dissolution of four commercial cellulosic samples, with different crystallinity rates and degrees of polymerization (DPs), in four solvent systems, known and used to dissolve cellulose. The dissolution conditions were optimized for the 16 various systems and followed by turbidity measurements. After regeneration, the samples were analyzed by thermal gravimetric analysis (TGA), scanning electron microscopy (SEM), and X-ray diffractometry (XRD) to study their modification.

Self-assembled polymeric vectors mixtures: characterization of the polymorphism and existence of synergistic effects in photodynamic therapy.

The objective of this work was to assess the relation between the purity of polymeric self-assemblies vectors solution and their photodynamic therapeutic efficiency. For this, several amphiphilic block copolymers of poly(ethyleneoxide-b-ε-caprolactone) have been used to form self-assemblies with different morphologies (micelles, worm-like micelles or vesicles). In a first step, controlled mixtures of preformed micelles and vesicles have been characterized both by dynamic light scattering and asymmetrical flow field flow fractionation (AsFlFFF).

Multimodal Dispersion of Nanoparticles: A Comprehensive Evaluation of Size Distribution with 9 Size Measurement Methods.

Purpose: Evaluation of particle size distribution (PSD) of multimodal dispersion of nanoparticles is a difficult task due to inherent limitations of size measurement methods. The present work reports the evaluation of PSD of a dispersion of poly(isobutylcyanoacrylate) nanoparticles decorated with dextran known as multimodal and developed as nanomedecine.

Methods: The nine methods used were classified as batch particle i.

Ozonation of sunflower oils: impact of experimental conditions on the composition and the antibacterial activity of ozonized oils.

Ozone can react with vegetable oils to produce ozonized oils which have antimicrobial properties and can be used in dermatology. The aim of this study was to evaluate the influence of ozonation conditions and of the initial fatty acid composition on iodine index (II), peroxide index (IP), acidity value (AV) of ozonized sunflower oils. The antibacterial activity of these products against the three bacterial strains that are more often involved in mastitis (Staphylococcus aureus, Escherichia coli and Streptococcus uberis) was also evaluated.

Asymmetrical flow field-flow fractionation with multi-angle light scattering and quasi-elastic light scattering for characterization of polymersomes: comparison with classical techniques.

Polymersomes formed from amphiphilic block copolymers, such as poly(ethyleneoxide-b-ε-caprolactone) (PEO-b-PCL) or poly(ethyleneoxide-b-methylmethacrylate), were characterized by asymmetrical flow field-flow fractionation coupled with quasi-elastic light scattering (QELS), multi-angle light scattering (MALS), and refractive index detection, leading to the determination of their size, shape, and molecular weight. The method was cross-examined with more classical ones, like batch dynamic and static light scattering, electron microscopy, and atomic force microscopy. The results show good complementarities between all the techniques; asymmetrical flow field-flow fractionation being the most pertinent one when the sample exhibits several different types of population.

Polymeric micelles encapsulating photosensitizer: structure/photodynamic therapy efficiency relation.

Various polymeric micelles were formed from amphiphilic block copolymers, namely, poly(ethyleneoxide-b-ε-caprolactone), poly(ethyleneoxide-b-d,l-lactide), and poly(ethyleneoxide-b-styrene). The micelles were characterized by static and dynamic light scattering, electron microscopy, and asymmetrical flow field-flow fractionation. They all displayed a similar size close to 20 nm.

Kinetic aspects and identification of by-products during the ozonation of bitertanol in agricultural wastewaters.

The degradation of bitertanol by ozone treatment is investigated. Solutions of bitertanol (8.4 μg mL(-1)) were prepared either by dissolution of the standard or by dilution of Gaucho Blé seed loading solution and then ozonated under different conditions.

Ozonation of imidacloprid in aqueous solutions: reaction monitoring and identification of degradation products.

This paper presents the degradation of imidacloprid by ozonation. Solutions of 39.0 μg/mL imidacloprid were prepared either by dissolution of standard or by dilution of Gaucho Blé(®) seed loading solution and then ozonated under different conditions.

Asymmetrical flow field-flow fractionation with multi-angle light scattering and quasi elastic light scattering for characterization of poly(ethyleneglycol-b-ɛ-caprolactone) block copolymer self-assemblies used as drug carriers for photodynamic therapy.

Poly(ethyleneoxide-b-ɛ-caprolactone) (PEO-b-PCL) self-assemblies in water were characterized by asymmetrical flow field-flow fractionation (AsFlFFF), with on-line coupling with quasi-elastic light scattering (QELS), multi-angle light scattering (MALS), refractive index and UV/Vis detection. We report here the AsFlFFF analysis of three different nanoparticular self-assembled systems of PEO-PCL polymers in aqueous media, each polymer differing by the mass of the PEO and PCL fragments. Thus, self-assembled water samples of {PEO(2000)-b-PCL(2600)}, {PEO(5000)-b-PCL(1400)} and {PEO(5000)-b-PCL(4000)} were analyzed by AsFlFFF.

Characterization of heat-induced changes in skim milk using asymmetrical flow field-flow fractionation coupled with multiangle laser light scattering.

Separation and size measurement of protein particles are a relevant approach to monitor heat-induced changes in skim milk. Unfortunately, no method is currently available at low cost and without excessive preparation of the samples. Therefore, the present study aimed at evaluating the interest of asymmetrical flow field-flow fractionation (AFlFFF) coupled with multiangle laser light scattering (MALLS) for this purpose.