Search results for "010401 analytical chemistry"
showing 10 items of 1284 documents
Extraction of Phenolic Compounds from Fresh Apple Pomace by Different Non-Conventional Techniques
2021
Red Delicious apple pomace was produced at laboratory scale with a domestic blender and different non-conventional extraction techniques were performed to isolate phenolic compounds, such as ultrasound-assisted extraction (UAE), ultraturrax extraction (UTE), accelerated solvent extraction (ASE) and pulsed electric field (PEF) extraction pre-treatment. Total phenolic content (TPC) was determined by Folin–Ciocalteu assay. Phloridzin, the main phenolic compound in apples, was determined by chromatographic analysis Q-TOF-LC/MS. The results obtained with these techniques were compared in order to identify the most efficient method to recover polyphenols. The highest value of TPC (1062.92 ± 59.80…
Phenolic compounds of herbal infusions obtained from some species of the Lamiaceae family
2018
Abstract The present investigation was to estimate the total phenolic content and composition of flavonoids and hydroxycinnamic acids in herbal infusions obtained from aerial parts of three Lamiaceae species (Dracocephalum moldavica, Ocimum americanum and Satureja hortensis). The total phenolic content of herbal infusions was determined using a spectrophotometric method, whereas the individual phenolics were assessed by high-performance liquid chromatography (HPLC). The HPLC method was developed and validated. The total phenolic content was measured by applying the Folin-Ciocalteu method with reference to gallic acid. Results were in the range from 29.39 to 65.38 mg estimated as gallic acid…
Application of Organic Monolithic Materials to Enantioseparation in Capillary Separation Techniques.
2017
This review article is primarily focused on the state-of-the-art of enantioseparations on organic monolithic materials. The article gives an overview of the chiral stationary phases and its application in capillary electrochromatography (CEC), and capillary- and nano-liquid chromatography (cLC and nLC). Since thousands of publications have been emerged from 2000’s and citing all these papers would extend the scope of this review; then, recent developments from last 10 years (2006 to 2016) will be mentioned. Mostly, stationary phases based on copolymers obtained from chiral functional monomers and surface modifications of organic monoliths with chiral ligands will be discussed. The effective…
Stability of mycophenolate mofetil in polypropylene 5% dextrose infusion bags and chemical compatibility associated with the use of the Equashield ® …
2019
Stability studies are necessary in healthcare settings as they facilitate fast, cost-effective and efficient work related to batch manufacturing and availability of supplies. We studied the stability of 1-10 mg/mL mycophenolate mofetil (MMF) in polypropylene 5% dextrose infusion bags prepared from Cellcept® and with a generic brand name (Micofenolato de Mofetilo Accord) at different storage temperatures. To ensure chemical compatibility during preparation, we also tested MMF sorption to the Equashield® closed-system drug transfer device used in this step. For this, a validated stability-indicating high-performance liquid chromatography method was developed for the quantification and identif…
Solid-State Transition Mechanisms of Ammonium Nitrate Phases IV, III, and II Investigated by Simultaneous Raman Spectrometry and Differential Scannin…
1993
The solid-state transition mechanisms of ammonium nitrate IV, III, and II were studied by measuring samples simultaneously by Raman spectrometry and differential scanning calorimetry (DSC). The Raman instruments were a Fourier transform Raman spectrophotometer and triple monochromator Raman spectrophotometer with charge-coupled-device (CCD) detector. The spectral data of the transitions were collected simultaneously with the calorimetric data in the temperature-scanning mode of the calorimeter and then isothermally between transitions. The phase transition from phase IV to phase III occurred through an intermediate phase II*, whose lifetime was seven minutes maximum when the onset temperat…
ZnO/polyaniline composite based photoluminescence sensor for the determination of acetic acid vapor
2020
In this study, we report a novel ZnO/polyaniline (PANI) nanocomposite optical gas sensor for the determination of acetic acid at room temperatures. ZnO nanorods, synthesized in powder form were coated by PANI (ZnO/ PANI) by chemical polymerization method. The obtained nanocomposites were deposited on glass substrate and dried overnight at room temperature. Structure and optical properties of ZnO/PANI nanocomposite have been studied by using X-ray diffraction, transmission electron microscopy, scanning electron microscopy, diffuse reflectance and photoluminescence spectroscopy. Tests towards acetic acids were performed in the range of concentrations 1–13 ppm. The adsorption of acetic a…
Quantum dots functionalised artificial peptides bioinspired to the D1 protein from the Photosystem II of Chlamydomonas reinhardtii for endocrine disr…
2021
Herein we describe the design and synthesis of novel artificial peptides mimicking the plastoquinone binding niche of the D1 protein from the green photosynthetic alga Chlamydomonas reinhardtii, also able to bind herbicides. In particular, molecular dynamics (MD) simulations were performed to model in silico the behaviour of three peptides, D1Pep70-H, D1Pep70-S264K and D1Pep70-S268C, as genetic variants with different affinity towards the photosynthetic herbicide atrazine. Then the photosynthetic peptides were functionalised with quantum dots for the development of a hybrid optosensor for the detection of atrazine, one of the most employed herbicides for weed control in agriculture as well …
PIPERADE: A double Penning trap for mass separation and mass spectrometry at DESIR/SPIRAL2
2021
International audience; A double Penning trap is being commissioned at CENBG Bordeaux for the future DESIR/SPIRAL2 facility of GANIL. The setup is designed to perform both high-resolution mass separation of the ion beam for trap-assisted spectroscopy, and high-accuracy mass spectrometry of short-lived nuclides. In this paper, the technical details of the new device are described. First offline tests with the purification trap are also presented, showing a mass resolving power of about 105.
Shape from polarization: a method for solving zenithal angle ambiguity
2012
International audience; We report a multispectral based method that permits the evolution of shape from polarization setup applied to 3D shape estimation of transparent objects. The setup is based on a polarization imaging technique which is a recent imaging method based on the analysis of the polarization state of the light in the observed scene. The technique has rapidly evolved with the development of electro-optic components and some polarization cameras are now available on the market. Shape from polarization consists in measuring the azimuthal and zenithal angles characterizing the normal of each point of the observed surface. We focus on the ambiguity in the measurement of the zenith…
Experimental Setup with Chaotic and Periodic Excitations for Cell Growth Studies
2020
The paper presents circuits used for excitation living cells to increase their growth rate. The main novelty is the proposal of using chaotic oscillations for the electromagnetic excitation. The research is in a preliminary phase and no conclusions have been yet derived for applications in biotechnology.