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1.
Int J Mol Sci ; 22(17)2021 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-34502323

RESUMO

The aim of the study was the multi-elemental analysis of aqueous humor (AH) collected from patients undergoing cataract surgery. The study included: 16 patients with age-related macular degeneration AMD (99 controls), 10 patients with retinopathy (105 controls), 61 patients with hypertension (54 controls), and 33 patients with coexisting diabetes (82 controls). The control groups were recruited from patients with a lack of co-existing disease characterizing the specified studied group. The measurements were performed by the use of inductively coupled plasma optical emission spectrometry (ICP-OES). The statistical analysis was carried out using non-parametric testing (Mann-Whitney U). The level of significance was set at p = 0.05. The data obtained revealed substantial variations in elemental composition between the test groups in comparison to the controls. However, the significant variations concerned only a few elements. The phosphorous (P) level and the ratio of P/Ca were significant in retinopathy and diabetes, whereas cobalt (0.091 ± 0.107 mg/L vs. 0.031 ± 0.075 mg/L; p = 0.004) was significant in AMD. In co-existing hypertension, the levels of tin (0.293 ± 0.409 mg/L vs. 0.152 ± 0.3 mg/L; p = 0.031), titanium (0.096 ± 0.059 mg/L vs. 0.152 ± 0.192 mg/L; p = 0.045), and ruthenium (0.035 ± 0.109 mg/L vs. 0.002 ± 0.007 mg/L; p = 0.006) varied in comparison to the controls. The study revealed inter-elemental interactions. The correlation matrices demonstrated the domination of the positive correlations, whereas negative correlations mainly concerned sodium.


Assuntos
Humor Aquoso/metabolismo , Catarata/metabolismo , Diabetes Mellitus/fisiopatologia , Retinopatia Diabética/fisiopatologia , Elementos Químicos , Hipertensão/fisiopatologia , Degeneração Macular/fisiopatologia , Idoso , Idoso de 80 Anos ou mais , Estudos de Casos e Controles , Catarata/epidemiologia , Catarata/patologia , Catarata/terapia , Extração de Catarata , Feminino , Seguimentos , Humanos , Cristalino/cirurgia , Masculino , Pessoa de Meia-Idade , Polônia/epidemiologia , Prognóstico
2.
Materials (Basel) ; 14(8)2021 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-33918857

RESUMO

In the present work, extraction with a solvent (cold acetone) was used to extract the assimilation pigments from spinach leaves. Then, the sorption capacity of selected plastics granules (polyvinyl chloride-PVC, polypropylene-PP, polyethylene-PE of different densities) was tested for the selective isolation of chlorophylls. Quantification of chlorophylls by HPLC (Zorbax Eclipse XDB-C18 column, the mobile phase: Acetonitrile/methanol/ethyl acetate 6:2:2, v/v) was based on chlorophyll-a content as the most common chlorophyll. The performed experiments prove that PVC containing electronegative chlorine exhibits favorable interactions toward chlorophyll by creating stable molecular complexes. The Fourier Transform Raman Spectroscopy (FT-Raman) and the molecular modeling were used to elucidate the structure of the created complexes. The optimal extraction requirements, the mass of sorbent, water-acetone ratio, time, and the composition of the elution solvent were all established. The optimized extraction conditions ensured a maximum extraction yield of chlorophylls of 98%. The chlorophyll-rich sorbent was re-extracted by acetone, leading to the recovery of 91% of chlorophylls in one step, adding the possibility of its re-use. The proposed effective and ecological method of obtaining the green dye from plants is cheap, simple, and efficient, avoiding organic solvents, utilizing the most widely used synthetic polymers in the world, being products difficult for utilization. The possibility to remove chosen fungicides cyprodinil, chlorothalonil, and thiabendazone from plant extract by PVC was also examined. The described method proposes a new application of synthetic polymers, which meets the criteria of sustainable green chemistry, simultaneously reaching the growing demand for pure natural compounds in the pharmaceutical and food industries.

3.
Int J Mol Sci ; 21(12)2020 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-32549300

RESUMO

Ionic liquids (ILs) are chemical compounds composed of ions with melting points below 100 °C exhibiting a design feature. ILs are commonly used as the so-called green solvents, reagents or highly efficient catalysts in varied chemical processes. The huge application potential of ionic liquids (IL) justifies the growing interest in these compounds. In the last decade, increasing attention has been devoted to the development of new methods in the synthesis of stable chiral ionic liquids (CILs) and their application in various separation techniques. The beginnings of the successful use of CILs to separate enantiomers date back to the 1990 s. Most chiral ILs are based on chiral cations or chiral anions. There is also a limited number of CILs possessing both a chiral cation and a chiral anion. Due to the high molecular diversity of both ions, of which at least one has a chiral center, we have the possibility to design a large variety of optically active structures, thus expanding the range of CIL applications. Research utilizing chiral ionic liquids only recently has become more popular. However, it is the area that still has great potential for future development. This review aimed to describe the diversity of structures, properties and examples of applications of chiral ionic liquids as new chiral solid materials and chiral components of the anisotropic environment, providing chiral recognition of enantiomeric analytes, which is useful in liquid chromatography, countercurrent chromatography and other various CIL-based extraction techniques including aqueous biphasic (ABS) extraction systems, solid-liquid two-phase systems, liquid-liquid extraction systems with hydrophilic CILs, liquid-liquid extraction systems with hydrophobic CILs, solid-phase extraction and induced-precipitation techniques developed in the recent years. The growing demand for pure enantiomers in the pharmaceutical and food industries sparks further development in the field of extraction and separation systems modified with CILs highlighting them as affordable and environmentally friendly both chiral selectors and solvents.


Assuntos
Fracionamento Químico/métodos , Líquidos Iônicos/química , Anisotropia , Catálise , Indústria Farmacêutica , Indústria Alimentícia , Solventes/química , Estereoisomerismo
4.
Molecules ; 24(22)2019 Nov 14.
Artigo em Inglês | MEDLINE | ID: mdl-31739645

RESUMO

Trace elements play an important role in the pathogenesis of several serious ophthalmological disorders, such as glaucoma, age-related macular degeneration (AMD), diabetic retinopathy, cataract, etc. This study aimed to measure alterations of chemical elements' (67) levels in the aqueous humor of patients undergoing cataract surgery. The pilot study included 115 patients, (age 74 ± 7.27, female 64.35%, male 35.65%). The aqueous levels of elements were measured by the use of the inductively coupled plasma optical emission spectrometry (ICP-OES), quality controlled with certified standards. The classification of elements based on their concentration was achieved by hierarchical cluster analysis. This is the first screening study that quantifies over 60 elements which are present in the fluid from the anterior chamber of the eye of cataract patients. The obtained results can be suitable for understanding and identifying the causes that may play a role in the initiation and progression of lens opacity.


Assuntos
Humor Aquoso/química , Catarata/metabolismo , Oligoelementos/análise , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Projetos Piloto
5.
Molecules ; 24(20)2019 Oct 21.
Artigo em Inglês | MEDLINE | ID: mdl-31640293

RESUMO

The aim of the study was to estimate the thiocyanate levels in saliva of cigarette smokers in comparison to e-cigarette smokers and nonsmokers. To improve our understanding of the influence of smoking on the oral level of thiocyanate, we conducted an assessment of human saliva, in 24 individuals (eight tobacco smokers, eight e-cigarette smokers, and eight nonsmokers). High-Performance Liquid Chromatography with ultraviolet detection (HPLC-UV) using a unique phosphatidylcholine column was applied in this assay. Thiocyanate ion was detected directly by its absorbance at 210 nm. The method presents a new application of the IAM (Immobilized Artificial Membrane) column for quantification of inorganic anions. The whole process meets the criteria of green chemistry because it was carried out without the use of organic solvents. For compensating matrix effects, an eight-point standard addition protocol was used to quantify the thiocyanate level in saliva samples. The calibration graphs were linear in the range of 5-100 mg L-1 with a correlation coefficient higher than 0.99. The thiocyanate concentrations in the saliva of tobacco smokers, e-cigarette smokers, and nonsmokers were found in the range of 121.25-187.54 mg L-1, 121.24-244.11 mg L-1, 33.03-79.49 mg L-1, respectively. The present study indicates an obvious statistically significant elevation in salivary thiocyanate level in tobacco smokers in comparison to nonsmokers. The phosphatidylcholine-based stationary phase proved to be suitable for the detection and quantification of the thiocyanate ion. The salivary thiocyanate levels in e-cigarette smokers were not significantly different in comparison to tobacco smokers but higher if compared to nonsmokers. The criterion for statistical significance was p < 0.05.


Assuntos
Saliva/química , Tiocianatos/análise , Fumar Tabaco/efeitos adversos , Adulto , Cromatografia Líquida de Alta Pressão , Sistemas Eletrônicos de Liberação de Nicotina , Química Verde , Humanos , Pessoa de Meia-Idade , Fosfatidilcolinas/química
6.
Molecules ; 24(9)2019 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-31064131

RESUMO

The aim of this research was to optimize the separation and quantitative determination of nitrites and nitrates in human saliva. HPLC with UV absorption (HPLC/DAD) using a phosphatidylcholine column (IAM.PC.DD2 Regis HPLC) was applied in this assay. Nitrates were detected directly by their absorbance at 210 nm, whereas nitrites were detected after oxidation to nitrates by potassium permanganate at acidic conditions. The kinetics of the permanganate-nitrite reaction was measured chromatographically. The calibration graph for nitrates was linear in the range of 0.5-35 µg mL-1 with a correlation coefficient of 0.9999. The limit of detection was 4.56 ng mL-1. The calibration graph for nitrites (after oxidation to nitrates) was linear in the range of 0.5-15 µg mL-1 with a correlation coefficient of 0.9972. The limit of detection was 4.21 ng mL-1. The nitrate concentrations in the saliva samples were found in the range of 8.98-18.52 µg mL-1, whereas nitrite was in the range of 3.50-5.34 µg mL-1.


Assuntos
Nitratos/análise , Nitritos/análise , Fosfatidilcolinas/química , Saliva/química , Bioensaio/métodos , Cromatografia Líquida de Alta Pressão/métodos , Cromatografia por Troca Iônica/métodos , Humanos , Limite de Detecção , Oxirredução , Permanganato de Potássio/química , Reprodutibilidade dos Testes
7.
Molecules ; 24(7)2019 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-30934973

RESUMO

Iodine is an essential nutrient necessary for the production of thyroid hormones. A valuable source of iodide, which is the bio-available iodine form could be mineral waters offered by different spas. In this work, the method capable of direct determination of iodide in mineral water samples based on IAM liquid chromatography on the phosphatidylcholine column (IAM.PC.DD2 Regis HPLC) with DAD detection without sample pretreatment or any pre-concentration steps is presented. The calibration graph for iodide was linear in the range of 0.5⁻10.0 mg L-1 with a correlation coefficient of 0.9996. The limit of detection was 22.84 ng mL-1. The relative recoveries were in the interval of 98.5⁻100.2% and the repeatability, expressed as a relative standard deviation (RSD) was less than 5%. The RSA (Response Surface Analysis) investigated the effect of the sample concentration and the injection volume. The iodide concentrations in the mineral water samples ranged from 0.58 to 2.88 mg L-1. The accuracy of the method was assessed through independent analysis by ICP-MS. Iodide levels measured by these two procedures did not significantly differ. The effects of interfering ions like HCO3-, Cl-, SO42-, F-, and Br- were also tested. The analysis has shown insignificant differences in the values of the iodide peak area and its height measured in multicomponent mixtures with an error smaller than 5%.


Assuntos
Cromatografia Líquida de Alta Pressão , Iodetos/análise , Águas Minerais/análise , Fosfatidilcolinas/química , Ânions/química , Íons , Controle de Qualidade , Reprodutibilidade dos Testes
8.
J Sep Sci ; 41(15): 3129-3142, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-29897661

RESUMO

Spinacia oleracea L. extract was immobilized on an octadecyl-bonded silica surface to produce a new sorbent for the solid-phase extraction of trace amounts of metal ions from aqueous neutral samples. A measurement of the metal content has been performed by using graphite furnace atomic absorption spectroscopy. The affinity of the investigated bivalent metal cations for the modified sorbent are in the order: Pb(II) > Cu(II) > Ni(II) > Zn(II) ≈ Cd(II) ≈ Co(II). The quantum-chemically calculated chlorophyll-a-metal ion binding energies were consistent with the measured affinities of the corresponding metal ions to the investigated sorbent. The maximum sorption capacity obtained for Pb(II) was equal to 1.44 µmol/g. The value of lead uptake was significantly higher in comparison to the one reported for other sorbents and biosorbents. Immobilized chlorophyll a is responsible for a chelation process with stoichiometry 1:1 owing to the porphyrin rings, which was confirmed by the quantitative analysis performed by reversed-phase high-performance liquid chromatography with diode array detection. The Toth adsorption isotherm model was applicable to the description of the adsorption process of either chlorophyll a or Pb(II). The structural analysis of sorbent was done using Fourier-transform Raman spectroscopy and scanning electron microscopy with an energy dispersive X-ray detector.


Assuntos
Chumbo/isolamento & purificação , Pigmentos Biológicos/química , Dióxido de Silício/química , Extração em Fase Sólida , Spinacia oleracea/química , Poluentes Químicos da Água/química , Chumbo/química , Processos Fotoquímicos , Fotossíntese , Pigmentos Biológicos/síntese química
9.
Artigo em Inglês | MEDLINE | ID: mdl-29100761

RESUMO

The new sorbent for solid phase extraction (SPE), based on silica gel modified with a copper (II), was obtained and its application for phospholipids removal from the human plasma was tested. SPE column conditioning requirements, the volume of the plasma, the composition of the elution solvent were all established. The efficacy of the removal of phospholipids was compared for different methods such as standard protein precipitation or HybridSPE Phospholipid Ultra and HybridSPE-PPT. The sample clean-up was verified by mass spectrometry (MS) and by monitoring of chromatograms in the region between 190nm and 400nm. The Fourier Transform Infrared Spectroscopy FT-IR and confocal Raman microscopy were used to evaluating the silica gel modifications and to show the structure of lipids confined in the silica pores.


Assuntos
Fosfolipídeos/sangue , Fosfolipídeos/isolamento & purificação , Extração em Fase Sólida/métodos , Cromatografia Líquida de Alta Pressão , Cobre/química , Humanos , Espectrometria de Massas , Sílica Gel/química
10.
J Sep Sci ; 40(11): 2374-2381, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28426156

RESUMO

We present the specific cooperative effect of a semisynthetic glycopeptide antibiotic teicoplanin and chiral ionic liquids containing the (1R,2S,5R)-(-)-menthol moiety on the chiral recognition of enantiomers of mandelic acid, vanilmandelic acid, and phenyllactic acid. Experiments were performed chromatographically on an Astec Chirobiotic T chiral stationary phase applying the mobile phase with the addition of the chiral ionic liquids. The stereoselective binding of enantiomers to teicoplanin in presence of new chiral ionic liquids were evaluated applying thermodynamic measurements and the docking simulations. Both the experimental and theoretical methods revealed that the chiral recognition of enantiomers in the presence of new chiral ionic liquids was enthalpy driven. The changes of the teicoplanin conformation occurring upon binding of the chiral ionic liquids are responsible for the differences in the standard changes in Gibbs energy (ΔG0 ) values obtained for complexes formed by the R and S enantiomers and teicoplanin. Docking simulations revealed the steric adjustment between the chiral ionic liquids cyclohexane ring (chair conformation) and the ß-d-glucosamine ring of teicoplanin and additionally hydrophobic interactions between the decanoic aliphatic chain of teicoplanin and the alkyl group of the tested salts. The obtained terpene derivatives can be considered as "structural task-specific ionic liquids" responsible for enhancing the chiral resolution in synergistic systems with two chiral selectors.


Assuntos
Líquidos Iônicos/química , Teicoplanina/química , Terpenos/química , Cromatografia Líquida de Alta Pressão , Estereoisomerismo
11.
Molecules ; 20(12): 22058-68, 2015 Dec 10.
Artigo em Inglês | MEDLINE | ID: mdl-26690392

RESUMO

A series of imidazolium and pyridinium ionic liquids with different anions (Cl(-), Br(-), BF4(-), PF6(-)) has been evaluated for their adsorption activity on silica gel. Quantification of the ionic liquids has been performed by the use of RP-HPLC with organic-aqueous eluents containing an acidic buffer and a chaotropic salt. Pseudo-second order kinetic models were applied to the experimental data in order to investigate the kinetics of the adsorption process. The experimental data showed good fitting with this model, confirmed by considerably high correlation coefficients. The adsorption kinetic parameters were determined and analyzed. The relative error between the calculated and experimental amount of ionic liquid adsorbed at equilibrium was within 7%. The effect of various factors such as initial ionic liquid concentration, temperature, kind of solvent, kind of ionic liquid anion and cation on adsorption efficiency were all examined in a lab-scale study. Consequently, silica gel showed better adsorptive characteristics for imidazolium-based ionic liquids with chaotropic anions from aqueous solutions in comparison to pyridinium ionic liquids. The adsorption was found to decrease with the addition of organic solvents (methanol, acetonitrile) but it was not sensitive to the change of temperature in the range of 5-40 °C.


Assuntos
Halogênios/química , Imidazóis/química , Líquidos Iônicos/química , Sílica Gel/química , Acetonitrilas/química , Adsorção , Cinética , Metanol/química , Extração em Fase Sólida/métodos , Termodinâmica
12.
J Pharm Biomed Anal ; 107: 501-11, 2015 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-25700183

RESUMO

It has been widely recognized that chromatography can be applied to derive parameters useful for anticipation of the pharmacological properties of xenobiotics. The purpose of this study was to evaluate the use of C18 stationary phase in chromatographic experiments as to assess antimycobacterial activity of series of novel thiosemicarbazides and their cyclization products: 1,2,4-triazole derivatives. Chromatographically determined lipophilicity descriptors log k(w), S and φ0 and computer generated molecular descriptors were obtained for 32 compounds and Rifampicin as a representative anti-tuberculosis drug. As experimental parameters were not significantly related to the calculated values, the data were analyzed by the principal component analysis PCA allowing for the extraction of "dipole moment" and "energy due to solvation" as the most powerful parameters from large set of diverse data. The approach ranked the examined analytes as active and inactive against Mycobacterium strains. More significant clustering of examined compounds was achieved by construction of 3D graph relating computational (dipole moment, energy due to solvation) and experimental log k(w) (MeOH) descriptors. It was proved that lack of substituent in the C5 position in the triazole ring appears to be characteristic for active derivatives. Provided conclusions can be taken into account in planning further synthesis of new derivatives with antimycobacterial activity.


Assuntos
Antibacterianos/química , Antibacterianos/farmacologia , Mycobacterium tuberculosis/efeitos dos fármacos , Semicarbazidas/química , Semicarbazidas/farmacologia , Triazóis/química , Triazóis/farmacologia , Cromatografia Líquida de Alta Pressão/métodos , Testes de Sensibilidade Microbiana/métodos , Análise de Componente Principal , Relação Quantitativa Estrutura-Atividade
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