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1.
Electrophoresis ; 45(1-2): 55-68, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37495859

RESUMO

Separation and identification of chiral molecules is a topic widely discussed in the literature and of fundamental importance, especially in the pharmaceutical and food fields, both from industrial and laboratory points of view. Several techniques are used to carry out these analyses, but high-performance liquid chromatography is often the "gold standard." The high costs of chiral columns, necessary for this technique, led researchers to look for an alternative, and capillary electrophoresis (CE) is a technique capable of overcoming some of the disadvantages of liquid chromatography, often providing comparable results in terms of sensitivity and robustness. We addressed this topic, already widely discussed in the literature, providing an overview of the last 6 years of the most frequent and recent applications of CE. To make the manuscript more effective, we decided to divide it into paragraphs that represent the main field of application, from enantioseparation in complex matrices (pharmacokinetic studies or toxicological dosage of drugs, analysis of environmental pollutants, and analyses of foods) to quality control analyses on pharmaceutical formulas. About these, which are the fields of most meaningful use, we mentioned some of the most innovative and performing methods, with a look to the future on the application of new materials used, such as chiral selectors, that can make these types of analyses accessible to all, reducing cost, time, and excessive use of toxic solvents.


Assuntos
Eletroforese Capilar , Eletroforese Capilar/métodos , Cromatografia Líquida , Estereoisomerismo , Cromatografia Líquida de Alta Pressão , Preparações Farmacêuticas
2.
Chirality ; 36(3): e23659, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38445305

RESUMO

Due to a great demand for amylose and cellulose polymeric chromatographic chiral columns, the enantiomeric separation of thiourea derivatives of naringenin was achieved on the different amylose (Chiralpak-IB) and cellulose chiral (Chiralcel-OJ and Chiralcel-OD-3R) columns with varied chromatographic conditions. The isocratic mobile phases used were ethanol and methanol, where ethanol/hexane and methanol/hexane were used as gradient mode and were prepared in volume/volume relation. The separation and resolution factors for all the enantiomers were in the range of 1.25 to 3.47 and 0.48 to 1.75, respectively. The enantiomeric resolution was obtained within 12 min making fast separation. The docking studies confirmed the chiral recognition mechanisms with binding affinities in the range of -4.7 to -5.7 kcal/mol. The reported compounds have good anticoagulant activities and may be used as anticoagulants in the future. Besides, chiral separation is fast and is useful for enantiomeric separation in any laboratory in the world.


Assuntos
Amilose , Flavanonas , Hexanos , Metanol , Estereoisomerismo , Celulose , Polímeros , Etanol , Tioureia
3.
Pflugers Arch ; 475(6): 691-709, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-37156970

RESUMO

Extracellular vesicles (EVs) enriched with bioactive molecules have gained considerable attention in nanotechnology because they are critical to intercellular communication while maintaining low immunological impact. Among biological matrices, urine has emerged as a noninvasive source of extracellular-contained liquid biopsy, currently of interest as a readout for physiological adaptations. Therefore, we aimed to evaluate chronic adaptations of endurance sport practice in terms of urinary EV parameters and evaluated by food consumption assessment. Two balanced groups of 13 inactive controls vs. triathlon athletes were enrolled; their urinary EVs were obtained by differential ultracentrifugation and analyzed by dynamic light scattering and transmission electron and atomic force microscopy. The cargo was analyzed by means of purine and miRNA content through HPLC-UV and qRT-PCR. Specific urinary EV signatures differentiated inactive versus endurance-trained in terms of peculiar shape. Particularly, a spheroid shape, smaller size, and lower roughness characterize EVs from triathletes. Metabolic and regulatory miRNAs often associated with skeletal muscle (i.e., miR378a-5p, miR27a-3p, miR133a, and miR206) also accounted for a differential signature. These miRNAs and guanosine in urinary EVs can be used as a readout for metabolic status along with the shape and roughness of EVs, novel informative parameters that are rarely considered. The network models allow scholars to entangle nutritional and exercise factors related to EVs' miRNA and purine content to depict metabolic signatures. All in all, multiplex biophysical and molecular analyses of urinary EVs may serve as promising prospects for research in exercise physiology.


Assuntos
Líquidos Corporais , Vesículas Extracelulares , MicroRNAs , Sistema Urinário , Humanos , MicroRNAs/metabolismo , Sistema Urinário/metabolismo , Vesículas Extracelulares/metabolismo , Líquidos Corporais/metabolismo , Purinas/metabolismo
4.
Anal Biochem ; 677: 115268, 2023 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-37524223

RESUMO

A polymer-based nanosensor and electrochemical methods were developed for the quantitative analysis of vanillin. The sample preparation was done using nano solid phase micro membrane tip extraction (NSPMMTE). A novel poly(phenylalanine)/TiO2/CPE sensor was built as the working electrode for the first time for the analysis of the vanillin substance. The electrochemical behavior and analytical performance of vanillin were examined in detail by cyclic voltammetry (CV) and differential pulse stripping voltammetry (DPSV) techniques via the oxidation process. The optimized modules of the DPSV technique that affected the vanillin peak current and peak potential were pH, pulse amplitude, step potential, and deposition time. The electroactive surface areas of bare CPE, TiO2/CPE, and poly(phenylalanine)/TiO2/CPE electrodes were found to be 0.135 cm2, 0.155 cm2, and 0.221 cm2, respectively. The limit of detection (LOD) was 32.6 µg/L in the 0.25-15.0 mg/L working range at pH 7.0. The selectivity of the proposed DPSV method for the determination of vanillin on the modified electrode was investigated in the presence of various organic and inorganic substances, and the determination of vanillin with high recovery was achieved with less than 5% relative error. The analytical application was applied in chocolate samples and the DPSV method was found highly efficient, reproducible, and selective.


Assuntos
Chocolate , Titânio/química , Polímeros/química , Técnicas Eletroquímicas/métodos , Eletrodos , Carbono/química
5.
J Sep Sci ; 46(21): e2300582, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37675810

RESUMO

The extraction of berberine was carried out from Berberis vulgaris, Berberis aquifolium, and Hydrastis canadensis plants using ethanol and water (70:30, v/v). The extracted berberine was characterized by ultraviolet-visible and Fourier-transform infrared spectroscopy. The purity of berberine was ascertained by thin-layer chromatography using n-propanol-formic acid-water (95:1:4) and (90:1:9) solvents. hRf values were in the range of 44-49 with compact spots (diameter 0.2-0.4 cm). HPLC was carried out using ammonium acetate buffer and acetonitrile in gradient mode with Zodiac (4.6 × 150 mm, 3 µm) column. The flow rate was 1.0 mL/min and detection was at 220 nm. The values of separation and resolution factors of the standard and the extracted berberine were in the range of 1.13-1.16 and 1.40-1.71, respectively. A comparison has shown that both thin-layer chromatography and high-performance liquid chromatography (HPLC) methods found applications in different situations and requirements. The extracted berberine samples were used to treat Leishmaniosis and the results showed better activity of berberine in comparison to the standard drug Amphotericin B. Briefly, the reported research is a novel and may be used to extract berberine from plants, separation and identification of berberine by thin layer chromatography and HPLC and to treat Leishmaniosis.


Assuntos
Berberina , Berberina/química , Cromatografia Líquida de Alta Pressão/métodos , Cromatografia em Camada Fina/métodos , Solventes/análise , Água
6.
Molecules ; 28(5)2023 Feb 24.
Artigo em Inglês | MEDLINE | ID: mdl-36903374

RESUMO

Nowadays, it is vital to have new, complete, and rapid methods to screen and follow pharmacotoxicological and forensic cases. In this context, an important role is undoubtedly played by liquid chromatography-tandem mass spectrometry (LC-MS/MS) thanks to its advanced features. This instrument configuration can offer comprehensive and complete analysis and is a very potent analytical tool in the hands of analysts for the correct identification and quantification of analytes. The present review paper discusses the applications of LC-MS/MS in pharmacotoxicological cases because it is impossible to ignore the importance of this powerful instrument for the rapid development of pharmacological and forensic advanced research in recent years. On one hand, pharmacology is fundamental for drug monitoring and helping people to find the so-called "personal therapy" or "personalized therapy". On the other hand, toxicological and forensic LC-MS/MS represents the most critical instrument configuration applied to the screening and research of drugs and illicit drugs, giving critical support to law enforcement. Often the two areas are stackable, and for this reason, many methods include analytes attributable to both fields of application. In this manuscript, drugs and illicit drugs were divided in separate sections, with particular attention paid in the first section to therapeutic drug monitoring (TDM) and clinical approaches with a focus on central nervous system (CNS). The second section is focused on the methods developed in recent years for the determination of illicit drugs, often in combination with CNS drugs. All references considered herein cover the last 3 years, except for some specific and peculiar applications for which some more dated but still recent articles have been considered.


Assuntos
Drogas Ilícitas , Espectrometria de Massas em Tandem , Humanos , Cromatografia Líquida/métodos , Espectrometria de Massas em Tandem/métodos , Medicina Legal , Monitoramento de Medicamentos
7.
Chirality ; 34(3): 514-520, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-34989017

RESUMO

Supercritical fluid chromatography and high-performance liquid chromatography techniques are popular for the chiral separations of different drugs and pharmaceuticals. Therefore, this article describes a comparative study of the chiral separation of some calcium channel antagonists such as verapamil, gallopamil, and nisoldipine. The columns used were Chiralpak IG and Chiralpak ID (250 mm × 4.6 mm, 5.0 µm). The separation was achieved by using a variety of mobile phases in both techniques. The retention, separation, and resolution factors in SFC were in the range of 1.36-7.30, 1.09-1.72, and 1.16-3.47, while these values in the case of HPLC were 1.03-2.42, 1.12-1.35, and 0.49-2.46. The complete resolution of gallopamil and verapamil was achieved successfully. The chiral recognition was controlled by hydrogen bondings, π-π interactions, dipole induced dipole interactions, van der Waal forces, and steric effects. SFC was found to be a better technique than HPLC because of quick separation, good separation power, economic, environment-friendly, and green technology.


Assuntos
Bloqueadores dos Canais de Cálcio , Cromatografia com Fluido Supercrítico , Cromatografia Líquida de Alta Pressão/métodos , Cromatografia com Fluido Supercrítico/métodos , Polissacarídeos/química , Estereoisomerismo
8.
Molecules ; 27(6)2022 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-35335207

RESUMO

Bioindicator plants are species that have the capacity to linearly uptake some elements (metal and metalloids) from the growing substrate, thus reflecting their concentration in the soil. Many factors can influence the uptake of these elements by plants, among which is the simultaneous presence of several metals, a common situation in contaminated or natural soils. A novel approach that can be used to validate the bioindication ability of a species growing on a polymetallic substrate is the design of experiment (DoE) approach. The aim of the present study was to apply the DoE in full factorial mode to model the Cu, Cd, Pb, Zn, and Cr bioindication capacity of Polygonum aviculare, used as the model plant. The results showed that P. aviculare has the ability to bioindicate Cd and Cr with a linear uptake (from 0.35 to 6.66, and 0.1 to 3.4 mg kg-1, respectively) unaffected by the presence of other metals. Conversely, the uptake of Pb, Cu, and Zn is strongly influenced by the presence of all the studied metals, making their concentration in the plant shoot not proportional to that of the soil. In conclusion, these preliminary results confirmed that the DoE can be used to predict the bioindicator abilities of a plant for several elements at the same time and to evaluate the interactions that can be established between variables in the growing medium and in the plant itself. However, more studies including other plant species are needed to confirm the effectiveness of this method.


Assuntos
Metais Pesados , Poluentes do Solo , Oligoelementos , Plantas , Solo , Poluentes do Solo/análise
9.
Molecules ; 27(6)2022 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-35335375

RESUMO

A new 5,7-dihydroxy-3'-methoxy-4'-acetoxyflavone-8-C-ß-d-arabinopyranoside-2″-O-(4‴-acetoxy)-glucoside (6) and three known flavone C-glycosides-5,7,3',4'-tetrahydroxyflavone-6-C-xyloside-8-C-ß-d-glucoside (lucenin-1) (7), 5,7,3'-trihydroxyflavone-6-C-glucoside-8-C-ß-d-glucoside (vicenin-2) (8), and 5,7,4'-trihydroxy-3'-methoxyflavone-6-C-ß-d-glucopyranoside-8-C-α-arabinopyranoside (chrysoeriol-6-C-ß-d-glucopyranoside-8-C-α-arabinopyranoside) (9)-were isolated from aerial parts of Scleranthus perennis L. (Caryophyllaceae). Their structures were determined through the use of comprehensive spectroscopic and spectrometric methods, and a method for the quantification of the major constituents of S. perennis and S. annuus L. was developed. Furthermore, the anti-collagenase and antioxidant activities of all isolated compounds obtained from extracts and fractions from both Scleranthus species were evaluated. The highest percentage of collagenase inhibition (at 400 µg/mL) was distinguished for methanolic extracts (22.06%, 32.04%) and ethyl acetate fractions (16.59%, 14.40%) from S. annuus and S. perennis. Compounds 6-9 displayed moderate inhibitory activity, with IC50 values ranging from 39.59-73.86 µM.


Assuntos
Antioxidantes , Caryophyllaceae , Antioxidantes/farmacologia , Colagenases , Flavonoides/química , Flavonoides/farmacologia , Glicosídeos/química
10.
Molecules ; 27(17)2022 Aug 23.
Artigo em Inglês | MEDLINE | ID: mdl-36080126

RESUMO

The presence of triclosan in water is toxic to human beings, hazardous to the environment and creates side effects and problems because this is an endocrine-disturbing water pollutant. Therefore, there is a great need for the separation of this notorious water pollutant at an effective, economic and eco-friendly level. The interface sorption was achieved on synthesized ionic liquid-based nanocomposites. An N-methyl butyl imidazolium bromide ionic liquid copper oxide nanocomposite was prepared using green methods and characterized by using proper spectroscopic methods. The nanocomposite was used to remove triclosan in water with the best conditions of time 30 min, concentration 100 µg/L, pH 8.0, dose 1.0 g/L and temperature 25 °C, with 90.2 µg/g removal capacity. The results obeyed Langmuir, Temkin and D-Rs isotherms with a first-order kinetic and liquid-film-diffusion kinetic model. The positive entropy value was 0.47 kJ/mol K, while the negative value of enthalpy was -0.11 kJ/mol. The negative values of free energy were -53.18, -74.17 and -76.14 kJ/mol at 20, 25 and 30 °C. These values confirmed exothermic and spontaneous sorption of triclosan. The combined effects of 3D parameters were also discussed. The supramolecular model was developed by simulation and chemical studies and suggested electrovalent bonding between triclosan and N-methyl butyl imidazolium bromide ionic liquid. Finally, this method is assumed as valuable for the elimination of triclosan in water.


Assuntos
Líquidos Iônicos , Nanocompostos , Triclosan , Poluentes Químicos da Água , Poluentes da Água , Purificação da Água , Adsorção , Brometos , Humanos , Concentração de Íons de Hidrogênio , Cinética , Termodinâmica , Água/química , Poluentes Químicos da Água/química , Purificação da Água/métodos
11.
Molecules ; 27(18)2022 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-36144585

RESUMO

This work was undertaken to explore the phytochemical composition, antioxidant, and enzyme-inhibiting properties of Neurada procumbens L. extracts/fractions of varying polarity (methanol extract and its fractions including n-hexane, chloroform, n-butanol, and aqueous fractions). A preliminary phytochemical study of all extracts/fractions, HPLC-PDA polyphenolic quantification, and GC-MS analysis of the n-hexane fraction were used to identify the phytochemical makeup. Antioxidant (DPPH), enzyme inhibition (against xanthine oxidase, carbonic anhydrase, and urease enzymes), and antibacterial activities against seven bacterial strains were performed for biological investigation. The GC-MS analysis revealed the tentative identification of 22 distinct phytochemicals in the n-hexane fraction, the majority of which belonged to the phenol, flavonoid, sesquiterpenoid, terpene, fatty acid, sterol, and triterpenoid classes of secondary metabolites. HPLC-PDA analysis quantified syringic acid, 3-OH benzoic acid, t-ferullic acid, naringin, and epicatechin in a significant amount. All of the studied extracts/fractions displayed significant antioxidant capability, with methanol extract exhibiting the highest radical-scavenging activity, as measured by an inhibitory percentage of 81.4 ± 0.7 and an IC50 value of 1.3 ± 0.3. For enzyme inhibition experiments, the n-hexane fraction was shown to be highly potent against xanthine oxidase and urease enzymes, with respective IC50 values of 2.3 ± 0.5 and 1.1 ± 0.4 mg/mL. Similarly, the methanol extract demonstrated the strongest activity against the carbonic anhydrase enzyme, with an IC50 value of 2.2 ± 0.4 mg/mL. Moreover, all the studied extracts/fractions presented moderate antibacterial potential against seven bacterial strains. Molecular docking of the five molecules ß-amyrin, campesterol, ergosta-4,6,22-trien-3ß-ol, stigmasterol, and caryophyllene revealed the interaction of these ligands with the investigated enzyme (xanthine oxidase). The results of the present study suggested that the N. procumbens plant may be evaluated as a possible source of bioactive compounds with multifunctional therapeutic applications.


Assuntos
Anidrases Carbônicas , Catequina , Plantas Medicinais , Triterpenos , 1-Butanol , Antibacterianos/farmacologia , Antioxidantes/química , Ácido Benzoico , Clorofórmio , Ácidos Graxos , Flavonoides/análise , Flavonoides/farmacologia , Hexanos , Ligantes , Metabolômica , Metanol/química , Simulação de Acoplamento Molecular , Fenóis/análise , Compostos Fitoquímicos/análise , Compostos Fitoquímicos/farmacologia , Extratos Vegetais/química , Plantas Medicinais/metabolismo , Estigmasterol , Terpenos , Trientina , Urease , Xantina Oxidase
12.
Anal Chem ; 93(4): 1957-1961, 2021 02 02.
Artigo em Inglês | MEDLINE | ID: mdl-33470800

RESUMO

This study introduces an innovative device for the noninvasive sampling and chromatographic analysis of different compounds present in exhaled breath aerosol (EBA). The new sampling device, especially in light of the recent COVID-19 pandemic that forced many countries to impose mandatory facemasks, allows an easy monitoring of the subject's exposure to different compounds they may come in contact with, actively or passively. The project combines the advantages of a fabric-phase sorptive membrane (FPSM) as an in vivo sampling device with a validated LC-MS/MS screening procedure able to monitor more than 739 chemicals with an overall analysis time of 18 min. The project involves the noninvasive in vivo sampling of the EBA using an FPSM array inserted inside an FFP2 mask. The study involved 15 healthy volunteers, and no restrictions were imposed during or prior to the sampling process regarding the consumption of drinks, food, or drugs. The FPSM array-LC-MS/MS approach allowed us to effectively exploit the advantages of the two complementary procedures (the convenient sampling by an FPSM array and the rapid analysis by LC-MS/MS), obtaining a powerful and green tool to carry out rapid screening analyses for human exposure to different compounds. The flexible fabric substrate, the sponge-like porous architecture of the high-efficiency sol-gel sorbent coating, the availability of a large cache of sorbent coatings, including polar, nonpolar, mixed mode, and zwitterionic phases, the easy installation into the facemask, and the possibility of sampling without interrupting regular activities provide FPSMs unparalleled advantages over other sampling techniques, and their applications are expected to expand to many other clinical or toxicological studies.


Assuntos
Exposição Ambiental , Membranas Artificiais , Têxteis , COVID-19/epidemiologia , COVID-19/virologia , Cromatografia Líquida de Alta Pressão/métodos , Humanos , Máscaras , Pandemias , Reprodutibilidade dos Testes , SARS-CoV-2/isolamento & purificação , Espectrometria de Massas em Tandem/métodos
13.
Anal Chem ; 93(49): 16308-16313, 2021 12 14.
Artigo em Inglês | MEDLINE | ID: mdl-34843645

RESUMO

Narcotic and psychotropic substances are natural, synthetic, or semisynthetic compounds that are present in both solid and liquid illicit products. The alterations effects on the central nervous system related to their use can be psycholeptic, psychoanaleptic, or psychodiseptic and are able to generate tolerance, addiction, or dependence phenomena, creating social and public order problems. In this scenario, the analytical evaluations that aim to determine these analytes in seized nonbiological samples, and which assume the character of judicial evidence, must meet high analytical requirements of reliability, transparency, and procedures uniformity at a national level. For the first time in the literature, the herein validated method is able to provide the simultaneous quantitative determination of 37 of the most common narcotic substances as well as the most commonly used excipients/adulterants found in seized illicit material. Additionally, the validated method can process both solid and liquid samples maintaining the precision and trueness levels (intraday and interday) in accordance with the U.S. Food and Drug Administration and European Medicines Agency international guidelines (<14.31 and <13.41%, respectively). Furthermore, it provides a simple and fast procedure for sample preparation using the dilute and shoot approach, exploiting the sensitivity and selectivity of the LC-MS/MS instrument configuration used and the signal acquisition in multiple reaction monitoring (MRM) mode (both positive and negative polarization modes).


Assuntos
Manejo de Espécimes , Espectrometria de Massas em Tandem , Cromatografia Líquida , Reprodutibilidade dos Testes , Estados Unidos
14.
Molecules ; 26(11)2021 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-34071519

RESUMO

Currently, forensic research is multidisciplinary with new methods and parameters useful to define the cause and time of death as well as survival/agony times. The identification of biochemical markers able to estimate agonal period has been studied by many forensic researchers. It is known that the estimation of agonal time in different types of death is not always easy, hence our interest in literature's data. The studies analyzed in this review confirm the important role of thanatobiochemistry for the estimation of survival times. Regardless of the death cause, the survival/agony time between the primary event and death influences markers concentrations in biological samples (e.g., blood, urine, cerebrospinal fluid). Different biomarkers can be used for qualitative evaluations in deaths with short and long agony (e.g., C-reactive protein, ferritin, GFAP, etc.). Instead, the quantitative interpretation showed limits due to the lack of reference cut-offs. Thanatobiochemistry is a useful tool to confirm what emerged from autopsies findings (macroscopic and histological analysis), but further studies are desirable to confirm the evidence emerging from our review of the literature.


Assuntos
Autopsia/métodos , Morte , Medicina Legal/métodos , Mudanças Depois da Morte , 8-Hidroxi-2'-Desoxiguanosina/sangue , Animais , Biomarcadores/sangue , Proteína C-Reativa/biossíntese , Proteínas de Transporte/sangue , Catecolaminas/metabolismo , Eletroquímica , Proteínas de Ligação a Ácido Graxo/sangue , Ferritinas/sangue , Proteína Glial Fibrilar Ácida/sangue , Humanos , Camundongos , Modelos Químicos , Subunidade beta da Proteína Ligante de Cálcio S100/sangue , Tireoglobulina/química , Hormônios Tireóideos/sangue
15.
Mikrochim Acta ; 187(6): 337, 2020 05 19.
Artigo em Inglês | MEDLINE | ID: mdl-32430628

RESUMO

A sensitive and readily deployable analytical method has been reported for the simultaneous analysis of pirimicarb (PRM) and fenitrothion (FEN) pesticide residues in environmental water samples using fabric phase sorptive extraction (FPSE) followed by high-performance liquid chromatography combined with photodiode array (HPLC-PDA) detector. Both pesticides were successfully determined with a Luna omega C18 column under isocratic elution mode by means of acetonitrile and phosphate buffer (pH 3.0) as the mobile phase. The quantitative data for PRM and FEN were obtained at their maximum wavelengths of 310 nm and 268 nm, respectively. The calibration plots were linear in the range 10.00-750.00 ng mL-1 and 10.00-900.00 ng mL-1 with correlation coefficient of 0.9984 and 0.9992 for PRM and FEN, respectively. Major FPSE experimental variables were investigated in detail, such as contact time with the FPSE membrane, pH and electrolyte concentration, and the volume and type of desorption solvent. Under the optimized conditions, the developed method showed satisfactory reproducibility with relative standard deviations less than 2.5% and low limits of detection of 2.98 and 3.02 ng mL-1 for PRM and FEN, respectively. The combined procedure allows for enhancement factors ranging from 88 to 113, with pre-concentration values of 125 for both analytes. The chromatographic resolutions were approx. 12 for FEN (retention factor of 3.52) and PRM (retention factor of 6.09), respectively, with a selectivity factor of 1.73. Finally, the validated method was successfully applied to real environmental water samples for the determination of these pesticides. Graphical abstract.


Assuntos
Carbamatos/análise , Fenitrotion/análise , Resíduos de Praguicidas/análise , Pirimidinas/análise , Celulose/química , Cromatografia Líquida de Alta Pressão , Dimetilpolisiloxanos/química , Lagos/análise , Limite de Detecção , Poliésteres/química , Lagoas/análise , Reprodutibilidade dos Testes , Rios/química , Extração em Fase Sólida/instrumentação , Extração em Fase Sólida/métodos , Têxteis , Poluentes Químicos da Água/análise
16.
Phytochem Anal ; 31(6): 687-699, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32291862

RESUMO

INTRODUCTION: The analysis of plant and herbal samples is a challenging task for analytical chemists due to the complexity of the matrix combined with the low concentration of analytes. In recent years different liquid-phase microextraction (LPME) techniques coupled with a variety of analytical equipment have been developed for the determination of both organic and inorganic analytes. OBJECTIVE: Over the past few years, the number of research papers in this field has shown a markedly growing tendency. Therefore, the purpose of this review paper is to summarise and critically evaluate research articles focused on the application of LPME techniques for the analysis of plant and herbal samples. RESULTS: Due to the complex nature of the samples, the direct application of LPME techniques to the analysis of plants has not often been done. LPME techniques as well as their modalities have been commonly applied in combination with other pretreatment techniques, including a solid-liquid extraction technique supported by mechanical agitation or auxiliary energies for plant analysis. Applications and the most important parameters are summarised in the tables. CONCLUSION: This review summarises the application of the LPME procedure and shows the major benefits of LPME, such as the low volume of solvents used, high enrichment factor, simplicity of operation and wide selection of applicable detection techniques. We can expect further development of microextraction analytical methods that focus on direct sample analysis with the application of green extraction solvents while fully automating procedures for the analysis of plant materials.


Assuntos
Microextração em Fase Líquida , Plantas , Solventes
17.
Molecules ; 25(17)2020 Aug 26.
Artigo em Inglês | MEDLINE | ID: mdl-32859012

RESUMO

Analysis of 4-cyanophenol and 3-nitrophenol was carried out using multi-walled carbon nanotubes-based solid-phase extraction (SPE) and capillary electrophoresis (CE) methods. Capillary electrophoresis was carried out with 18 kV voltage, 214 nm detection, and phosphate buffer (pH 7.0, 15 mM) as background electrolyte at 25 ± 1 °C temperature with 15.05 and 16.5 min migration times of 4-cyanophenol and 3-nitrophenol. The separation and resolution factors were 1.10 and 2.90. The optimized experimental conditions were 40 mg/L concentration, 1.0 g multi-walled carbon nanotubes (MWCNTs) per SPE cartridge, 5.0 mL/min flow rate of water, 0.1 mL flow rate of eluting solvent. The maximum recoveries were 91% and 98% at 0.1 mL/min flow rate of 4-cyanophenol and 3-nitrophenol. These methods were applied successfully for extraction and estimation of 4-cyanophenol and 3-nitrophenol in the municipal wastewater. The reported methods are reproducible, efficient, and practical for the estimation of these phenols in water.


Assuntos
Nanotubos de Carbono/química , Nitrofenóis/análise , Fenóis/análise , Água/química , Eletroforese Capilar , Extração em Fase Sólida
18.
Molecules ; 25(5)2020 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-32155959

RESUMO

Phenolic compounds are secondary metabolites that are found ubiquitously in plants, fruits, and vegetables. Many studies have shown that regular consumption of these compounds could have a positive effect on our health. The aim of this study was to compare the phytochemical contents of the water extracts from three different plants used as folk remedies in Turkey: Aesculus hippocastanum, Olea europaea, and Hypericum perforatum. A liquid chromatography-electrospray tandem mass spectrometry (LC-ESI-MS/MS) analysis was performed to explore the phenolic profiles. The biological activities of these extracts were also evaluated in terms of their antioxidant activities (2,2-diphenyl-1-picrylhydrazyl DPPH, 2,2'-azino-bis-(3-ethylbenzothiazoline-6-sulfonic acid ABTS, Ferric Reducing Antioxidant Power Assay FRAP, cupric ion reducing antioxidant capacity CUPRAC, ß-carotene, phosphomolybdenum, and metal chelating) and enzyme inhibitory properties (against acetylcholinesterase, butyrylcholinesterase, and tyrosinase). The aqueous extract of H. perforatum showed the highest levels of total phenolic, flavonoid, and saponin contents. Protocatechuic acid, vanillic acid, verbascoside, hesperidin, hyperoside, apigenin 7-hexosides, and quercetin were the most common compounds found in this species. The results confirm that A. hippocastanum, O. europaea, and H. perforatum represent a potential source of natural-derived molecules with positive properties that could be used as valid starting point for new food supplements, and drugs in the pharmaceutical, cosmetic, and food industries.


Assuntos
Aesculus/enzimologia , Hypericum/enzimologia , Medicina Tradicional , Olea/enzimologia , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Antioxidantes/química , Antioxidantes/farmacologia , Flavonoides , Fenóis , Compostos Fitoquímicos/química , Compostos Fitoquímicos/farmacologia , Saponinas , Turquia
19.
Molecules ; 25(12)2020 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-32545471

RESUMO

Ethanol (ethylic alcohol) represents the most commonly used drug worldwide and is often involved in clinical and forensic toxicology. Based on several reports, excessive alcohol consumption is the main contributing factor in traffic accidents, drownings, suicides, and other crimes. For these reasons, it becomes essential to analyze the alcohol concentration during autopsy. Although blood is usually used for alcohol analysis in post-mortem cases, it could suffer alterations, putrefaction, and microbial contaminations. As an alternative to whole blood, vitreous humor has been successfully used in medico-legal studies. In this work, post-mortem specimens were analyzed for ethanol determination. The analysis of blood and vitreous humor were carried-out using gas chromatography-flame ionized detector (GC-FID) with a total run time of 6 min. The method was validated in terms of limit of detection, limit of quantification, dynamic range, sensibility, recovery, precision and trueness. A linear regression analysis indicated a coefficient of determination (R2) of 0.9981. The study confirmed no statistically differences between alcohol concentration in blood and vitreous humor, leading vitreous humor as an excellent matrix that could be used as an alternative to whole blood in toxicological analysis in cases where blood is not available.


Assuntos
Autopsia/métodos , Etanol/análise , Corpo Vítreo/química , Líquidos Corporais/química , Cromatografia Gasosa/métodos , Etanol/sangue , Toxicologia Forense/métodos , Humanos , Mudanças Depois da Morte
20.
Molecules ; 25(23)2020 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-33297520

RESUMO

The increased risk of illness and disability is related to the age inevitable biological changes. Oxidative stress is a proposed mechanism for many age-related diseases. The crucial importance of polyphenol pharmacophore for aging process is largely described thanks to its effects on concentrations of reactive oxygen species. Resveratrol (3,5,4'-trihydroxy-trans-stilbene, RSV) plays a critical role in slowing the aging process but has a poor bioavailabity after oral intake. In this present work, a series of RSV derivatives was designed, synthesized, and evaluated as potential antioxidant agents. These derivatives contain substituents with different electronic and steric properties in different positions of aromatic rings. This kind of substituents affects the activity and the bioavailability of these compounds compared with RSV used as reference compound. Studies of Log P values demonstrated that the introduction of halogens gives the optimum lipophilicity to be considered promising active agents. Among them, compound 6 showed the higher antioxidant activity than RSV. The presence of trifluoromethyl group together with a chlorine atom increased the antioxidant activity compared to RSV.


Assuntos
Técnicas de Química Sintética , Estilbenos/síntese química , Estilbenos/farmacologia , Animais , Linhagem Celular , Halogenação , Humanos , Camundongos , Modelos Teóricos , Estrutura Molecular , Estilbenos/química
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