114 research outputs found

    Chiral separation and analysis of antifungal drugs by chromatographic and electromigration techniques: Results achieved in 2010–2020

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    AbstractThe determination and separation of enantiomers is an interesting and important topic of research in various fields, e.g., biochemistry, food science, pharmaceutical industry, environment, etc. Although these compounds possess identical physicochemical properties, a pair of enantiomers often has different pharmacological, toxicological, and metabolic activities. For this reason, chiral discrimination by using chromatographic and electromigration techniques has become an urgent need in the pharmaceutical field. This review intends to offer the "state of the art" about the separation of chiral antifungal drugs and several related precursors by both liquid and gas chromatography, as well as electromigration methods. This overview is organized into two sections. The first one describes general considerations on chiral antifungal drugs. The second part deals with the main analytical methods for the enantiomeric discrimination of these drugs, including a brief description of chiral selectors and stationary phases. Moreover, many recent applications attesting the great interest of analytical chemists in the field of enantiomeric separation are presented

    Application of a Low Transition Temperature Mixture for the Dispersive Liquid-Liquid Microextraction of Illicit Drugs from Urine Samples

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    The use of psychoactive substances is a serious problem in today's society and reliable methods of analysis are necessary to confirm their occurrence in biological matrices. In this work, a green sample preparation technique prior to HPLC-MS analysis was successfully applied to the extraction of 14 illicit drugs from urine samples. The isolation procedure was a dispersive liquid-liquid microextraction based on the use of a low transition temperature mixture (LTTM), composed of choline chloride and sesamol in a molar ratio 1:3 as the extracting solvent. This mixture was classified as LTTM after a thorough investigation carried out by FTIR and DSC, which recorded a glass transition temperature at −71 °C. The extraction procedure was optimized and validated according to the main Food and Drug Administration (FDA) guidelines for bioanalytical methods, obtaining good figures of merit for all parameters: the estimated lower limit of quantitation (LLOQ) values were between 0.01 µg L−1 (bk-MMBDB) and 0.37 µg L−1 (PMA); recoveries, evaluated at very low spike levels (in the ng-µg L−1 range), spanned from 55% (MBDB) to 100% (bk-MMBDB and MDPV); finally, both within-run and between-run precisions were lower than 20% (LLOQ) and 15% (10xLLOQ)

    Polyphenols Extraction from Hazelnut Skin Using Water as Solvent: Equilibrium Studies and Quantification of the Total Extractable Polyphenols

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    In this work, a system for the extraction of antioxidant agents from waste vegetal matrices was studied. To this end, the extraction of polyphenols from food waste hazelnut skins was taken into consideration as a case study and a continuous set-up using distilled water at 70 °C as a solvent has been developed. Various extraction cycles were performed at different solid/liquid ratios (ranging from 2 to 5.7 g/l) in order to study the effect of this parameter on extraction efficiency. Through a mass balance, data obtained from the various cycles were used to calculate the total extractable polyphenols, and a value of 0.114 g of polyphenols per g of hazelnut skin was evaluated. Moreover, for two selected cycles the polyphenols concentration in the aqueous solution was measured at different time intervals in order to determine the extraction time, and in both tests it reached a plateau within the first hour. Finally, equilibrium concentrations of polyphenols in liquid and solid phases of the six tests were correlated by a linear isotherm equation, and a partition coefficient of 0.0368 l/g was evaluated through a fitting of experimental data

    Salivary Proteomic Analysis and Acute Graft-versus-Host Disease after Allogeneic Hematopoietic Stem Cell Transplantation

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    Abstract Graft-versus-host disease (GVHD) is the major life-threatening complication after allogeneic hematopoietic stem cell transplantation (allo-HSCT), developing in 35%-70% of all allo-HSCT recipients despite immunosuppressive prophylaxis. The recent application of proteomic tools that allow screening for differentially expressed or excreted proteins in body fluids could possibly identify specific biomarkers for GVHD. Whole saliva is highly attractive for noninvasive specimen collection. In the present study, we collected saliva specimens from 40 consecutives patients who underwent allo-HSCT between December 2008 and March 2011 at our institution. The specimens were analyzed by HPLC coupled to electrospray-ionization mass spectrometry. Variable expression of S100 protein family members (S100A8, S100A9, and S100A7) was detected. Fourteen of 23 patients with GVHD demonstrated the presence of S100A8, compared with only 2 patients without GVHD and 0 patients in the control group ( P = .001). S100A7 was detectable in 11 of the 23 patients with GVHD but was absent in the other 2 groups ( P = .0001). S100A9-short was detected in 20 patients with GVHD, in 9 patients without GVHD, and in 8 healthy volunteers ( P = .01) Further studies are needed to clarify the role of these proteins as a marker of GVHD or as an index of mucosal inflammation

    Large-scale profiling of carotenoids by using non aqueous reversed phase liquid chromatography-photodiode array detection–triple quadrupole linear ion trap mass spectrometry: application to some varieties of sweet pepper (Capsicum annuum L.)

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    Analysis of carotenoids is very complex and demanding in terms of both separation and detection. In this article, an analytical strategy relying on high-performance liquid chromatography-photodiode array detection-tandem mass spectrometry (HPLC-PAD-MS/MS) is presented for the large-scale screening of these phytochemicals. Separation was realized by means of Non-Aqueous Reversed Phase (NARP) chromatography on a triacontyl stationary phase kept at subambient temperature, using a mobile phase compatible with atmospheric pressure chemical ionization (APCI). The standards of 14 analytes were used to optimize the method and to predict the chromatographic behaviour of untargeted carotenoids. MS and MS/MS data, obtained during Information Dependent Acquisition (IDA) experiments, were utilized to set up a sensitive HPLC- selected reaction monitoring (SRM) method. Relative abundance between SRM ion currents (ion ratio) allowed the MS distinction of structural isomers (for example, bicyclic, monocyclic and acyclic isomers), while the identification of geometrical isomers was based on Qratio and fine structure, as calculated from UV–vis spectra. The comparison of LC-PAD- SRM chromatograms, acquired after applying two different extraction procedures (matrix solid-phase dispersion and overnight cold saponification), allowed verifying that sweet peppers are a good source of xanthophylls, prevalently occurring as esterified forms. The overall strategy could identify more than 40 carotenoids in some sweet pepper varieties (Jolly, horn and sweet chili pepper) available on the Italian and European food market

    Advanced analytical techniques for fat-soluble vitamin analysis

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    This review presents advancements in sample preparation and liquid chromatographic methods made during the last 10 years for the fat-soluble vitamin (FSV) analysis in foods. Since activity. and bioavailability of organic micronutrients (MOs) depend on the form in which they are present in a food, special emphasis has been given to the most recent techniques, instruments and approaches which have allowed the extraction and separation of various vitamin homologues as well as the comprehensive MO profiling in foods. Due to the numerous ancillary advantages, miniaturized techniques which have been applied in this analysis field are also discussed in this review. A number of selected applications are proposed to enable readers to access the most recent developments and trends aimed at gaining more in-depth knowledge of the vitamin composition of foods. (C) 2016 Elsevier B.V. All rights reserved

    Analysis of Enantiomers in Products of Food Interest

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    The separation of enantiomers has been started in the past and continues to be a topic of great interest in various fields of research, mainly because these compounds could be involved in biological processes such as, for example, those related to human health. Great attention has been devoted to studies for the analysis of enantiomers present in food products in order to assess authenticity and safety. The separation of these compounds can be carried out utilizing analytical techniques such as gas chromatography, high-performance liquid chromatography, supercritical fluid chromatography, and other methods. The separation is performed mainly employing chromatographic columns containing particles modified with chiral selectors (CS). Among the CS used, modified polysaccharides, glycopeptide antibiotics, and cyclodextrins are currently applied

    Advances in Food Analysis

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    This Topical Collection of Molecules provides the most recent advancements and trends within the framework of food analysis, confirming the growing public, academic, and industrial interest in this field. The articles broach topics related to sample preparation, separation science, spectroscopic techniques, sensors and biosensors, as well as investigations dealing with the characterization of macronutrients, micronutrients, and other biomolecules. It offers the latest updates regarding alternative food sources (e.g., algae), functional foods, effects of processing, chiral or achiral bioactive compounds, contaminants, and every topic related to food science that is appealing to readers. Nowadays, the increasing awareness of the close relation among diet, health, and social development is stimulating demands for high levels of quality and safety in agro-food production, as well as new studies to fill gaps in the actual body of knowledge about food composition. For these reasons, modern research in food science and human nutrition is moving from classical methodologies to advanced instrumental platforms for comprehensive characterization. Nondestructive spectroscopic and imaging technologies are also proposed for food process monitoring and quality control in real time

    Capillary electromigration techniques applied to pollutant analysis—A review

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    The analysis of pollutants such as pesticides, herbicides, insecticides, heavy metal ions, etc. is an important topic in the field of research, health, and the environment as these compounds, even if in traces, can create serious problems for the health of humans and animals. Therefore, reliable analytical methods, for the determination of these compounds, are requested. Among them, capillary electrophoretic techniques have been successfully applied for their separation and analysis. In this review paper, the main features of electromigration techniques (capillary zone electrophoresis, capillary isotachophoresis, capillary electrokinetic chromatography, and capillary electrochromatography) have been briefly reported. Selected applications reported in the period 2018–2023-March of the electromigration techniques applied to the analysis of pollutants are presented and discussed

    Exploring the performance of cellulose tris-3,5-dichlorophenylcarbamate as a stationary phase for the chiral electro-chromatographic separation of azole antifungals

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    In this study, the enantiorecognition and separation performance of cellulose tris-3,5-dichlorophenylcarbamate (CDCPC) as the chiral selector for the enantioseparation of some chiral antifungal compounds was investigated. The CDCPC was bonded to 5 µm porous silica particles and the stationary phase packed into fused silica capillaries (250 mm x 75 µm I.D.) using the ''slurry method''. The column was used for the separation of twelve selected azole compounds in their enantiomers by capillary electrochromatography (CEC). To study chiral recognition, the mobile phase was modified changing the organic solvent, water content, buffer type, concentration, and pH. Each change resulted in the enhancement of specific interactions at the expense of others, leading to chiral recognition. Their effects on retention factors, enantiomeric resolution, and peak broadening are critically discussed. The developed methodology was used as an appropriate test bench to evaluate the stability of the stationary phase under different mobile phase conditions, demonstrating a remarkable enantioselective capacity even after several tens of hours of continuous use. The optimized CEC-UV method was very effective in the enantiomeric separation of seven out of twelve azole fungicides, totaling fourteen separated peaks in a single 30 min run analysis
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