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1.
Food Chem Toxicol ; 189: 114730, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38740239

RESUMO

In this study, microplastic contamination in water, natural mineral water and mineral water, sparkling soft drinks, cold tea and some traditional beverages marketed in Türkiye were assessed. Microplastics physically and chemically characterized by microscope and ATR/FT-IR, respectively. Microplastics were detected in 9 out of 47 beverage samples. A total of 250 microplastics with 5 different polymers, 2 different shapes, and 7 different colours were detected in 47 beverage samples. The average microplastic concentration was 2.24 ± 9.86 particles/L for all beverages analysed. The highest average microplastic concentration was found in mineral waters in glass bottles (average 11.3 particles/L). No microplastics were found in cold tea and other drinks. The total annual microplastic exposure from beverage consumption in male and female individuals aged >15 years was 2029 and 1786 particles/mL/year, respectively. The microplastic load index category of all beverage samples was determined as "moderate". The average pRi level of all beverages was 117 ± 260 and the risk level was determined as "low". The study provides evidence that microplastics are common in beverages and that microplastics are directly ingested by humans.


Assuntos
Bebidas , Exposição Dietética , Contaminação de Alimentos , Microplásticos , Microplásticos/análise , Humanos , Medição de Risco , Bebidas/análise , Contaminação de Alimentos/análise , Feminino , Masculino , Poluentes Químicos da Água/análise , Adolescente
2.
Food Chem Toxicol ; 175: 113698, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-36889431

RESUMO

In this study, the characterization of microplastics of table salts (n = 36) was determined by FT - IR. Then, individuals' exposure to microplastics from table salt consumption was calculated with a deterministic model, and finally, a risk assessment of table salt was performed using the polymer risk index. On average, 44 ± 26, 38 ± 40, 28 ± 9, and 39 ± 30 microplastics/kg were detected in rock salts (n = 16), lake salts (n = 12), sea salts (n = 8), and all salts (n = 36). Microplastics with 10 different polymer types (CPE, VC-ANc, HDPE, PET, Nylon-6, PVAc, EVA, PP, PS, Polyester), 7 different colors (black, red, colorless, blue, green, brown, white, gray), and 3 different shapes (fiber, granulated, film) were found in table salts. The daily, annual and lifetime (70-year) exposures to microplastics from table salt consumption in 15+-year-old individuals (general) were calculated to be 0.41 microplastic particles/day, 150 microplastic particles/year and 10,424 microplastic particles/70-year, respectively. The average microplastic polymer risk index of all table salts was calculated as 182 ± 144 and the risk level is in the medium. In order to minimize microplastic contamination in table salts, protective measures should be taken at the source of the salt, and production processes should be improved.


Assuntos
Microplásticos , Poluentes Químicos da Água , Humanos , Adolescente , Plásticos/toxicidade , Cloreto de Sódio na Dieta/análise , Sais , Turquia , Monitoramento Ambiental , Poluentes Químicos da Água/toxicidade , Poluentes Químicos da Água/análise , Medição de Risco
3.
Spectrochim Acta A Mol Biomol Spectrosc ; 228: 117804, 2020 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-31806475

RESUMO

In this study, novel peripherally 4-[(1H-benzimidazol-1-yl)methoxy] substituted Zn(II) (3) Cu(II) (4) and Co(II) (5) phthalocyanines were prepared and their structures were characterized spectroscopically. The light absorption behaviors of the synthesized compounds (3-5) were studied by UV-Vis spectroscopy at different concentrations in different solvents. The urease inhibition activities of the synthesized compounds were also investigated. Among the synthesized molecules, compound 4 showed the best inhibitory effect against jack bean urease with IC50 values of 0.0036 ±â€¯0.0010 µM.


Assuntos
Inibidores Enzimáticos , Indóis , Simulação de Acoplamento Molecular , Proteínas de Plantas , Urease , Inibidores Enzimáticos/síntese química , Inibidores Enzimáticos/química , Indóis/síntese química , Indóis/química , Isoindóis , Proteínas de Plantas/antagonistas & inibidores , Proteínas de Plantas/química , Relação Estrutura-Atividade , Urease/antagonistas & inibidores , Urease/química
4.
Spectrochim Acta A Mol Biomol Spectrosc ; 153: 478-87, 2016 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-26397034

RESUMO

The synthesis and characterization of novel peripherally tetra [1,2,4]-triazole substituted metal-free phthalocyanine and its metal complexes (Zn(II), Ni(II), Pb(II), Cu(II) and Fe(II)) and the investigation of electrochemical and spectroelectrochemical properties of metal-free, Zn(II), Pb(II), Fe(II) phthalocyanines were performed for the first time in this study. Electrochemical characterizations of the complexes were performed with voltammetric and in situ spectroelectrochemical measurements. Voltammetric responses of the complexes supported the proposed structures, since complexes bearing redox inactive Pc ring metal centers just gave Pc based electron transfer reactions, while iron phthalocyanine went to metal based electron transfer reaction in addition to the Pc based ones. Electron withdrawing nature of [1,2,4]-triazole substituents shifted the redox processes toward the positive potentials. All complexes were electropolymerized during the oxidation reactions in dichloromethane (DCM) solvent. Types of the metal center of the complexes altered the electropolymerization reactions of the complexes. Spectra and colors of the electrogenerated redox species of the complexes were also determined with in situ spectroelectrochemical and in situ electrocolorimetric measurements.

5.
Spectrochim Acta A Mol Biomol Spectrosc ; 133: 272-80, 2014 Dec 10.
Artigo em Inglês | MEDLINE | ID: mdl-24952089

RESUMO

In this study, novel phthalonitrile derivative (3) was synthesized by the reaction between 4-nitrophthalonitrile (2) and a triazole derivative (1) containing pyridine moiety. Crystal structure of compound (3) was characterized by X-ray diffraction. New metal free and metallo-phthalocyanine complexes (Zn, Cu, and Mg) were synthesized using the phthalonitrile derivative (3). Cationic derivatives of these phthalocyanines (5, 7, 9, and 11) were prepared from the non-ionic phthalocyanines (4, 6, 8, and 10). All proposed structures were supported by instrumental methods. The aggregation behaviors of the phthalocyanines (4-11) were investigated in different solvents such as dimethylsulfoxide (DMSO), N,N-dimethylformamide (DMF), chloroform and water. Water soluble cationic Pcs (5, 7, 9, and 11) aggregated in water and sodium dodecyl sulfate was used to prevent the aggregation. The second derivatives of the UV-Vis spectra of aggregated Pcs were used for analyzing the Q and B bands of aggregated species. Thermal behaviors of the phthalocyanines were also studied. In addition, anti-bacterial properties of the phthalocyanines were investigated. We used four gram negative and two gram positive bacteria to determine antibacterial activity of these compounds. Compound 7 has the best activity against the all bacteria with 125µg/mL of MIC value. Compounds 4, 6, and 10 have the similar effect on the bacteria with 250µg/mL of MIC value.


Assuntos
Antibacterianos/química , Cobre/química , Indóis/química , Magnésio/química , Compostos Organometálicos/química , Zinco/química , Antibacterianos/farmacologia , Bactérias/efeitos dos fármacos , Infecções Bacterianas/tratamento farmacológico , Cobre/farmacologia , Cristalografia por Raios X , Humanos , Indóis/farmacologia , Isoindóis , Magnésio/farmacologia , Modelos Moleculares , Compostos Organometálicos/farmacologia , Solubilidade , Água/química , Zinco/farmacologia
6.
Spectrochim Acta A Mol Biomol Spectrosc ; 122: 142-52, 2014 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-24309175

RESUMO

In this paper, computational studies were carried out on anastrozole and letrozole, chemotherapy drugs used against breast cancer. Optimization and frequency calculations were performed at B3LYP/6-31G (d) basis set and vibrational frequencies were assignment. Single point calculations were performed at DFT method with a hybrid functional B3LYP/6-311G (d, p) basis set. Theoretical NMR data were obtained at DFT method with a hybrid functional B3LYP/6-311G++ (2d, p) with GIAO (Gauge-Independent Atomic Orbital). IEF-PCM method was used as solvation model. NBO calculations were performed by the same basis set and calculation method with single point calculation. Global and localized reactivity parameters; fukui indices (f) chemical hardness (η), softness (S), chemical potential (µ), electronegativity (χ) and electrophilicity index (ω) were calculated. All computational parameters were compared with the experimental results obtained from the literature.


Assuntos
Antineoplásicos/uso terapêutico , Neoplasias da Mama/tratamento farmacológico , Simulação por Computador , Nitrilas/uso terapêutico , Triazóis/uso terapêutico , Anastrozol , Antineoplásicos/química , Espectroscopia de Ressonância Magnética Nuclear de Carbono-13 , Feminino , Humanos , Letrozol , Modelos Moleculares , Conformação Molecular , Nitrilas/química , Espectroscopia de Prótons por Ressonância Magnética , Eletricidade Estática , Triazóis/química , Vibração
7.
Artigo em Inglês | MEDLINE | ID: mdl-23800773

RESUMO

The molecular structure of the substituted phthalonitrile was analyzed crystallographically and compared with optimized geometric structure. The structural properties of the compound such as energy, vibrational frequency, ground state transitions, (1)H and (13)C NMR chemical shifts, NBO analysis and hyperpolarizability were computed by DFT (Density Functional Theory) method and compared with experimental results. The novel Mg(II) and Sn(II) phthalocyanines synthesized from the substituted phthalonitrile and their aggregation behaviors were investigated in different solvents and at different concentrations in DMSO.


Assuntos
Complexos de Coordenação/química , Indóis/química , Magnésio/química , Nitrilas/química , Pirazóis/química , Estanho/química , Complexos de Coordenação/síntese química , Indóis/síntese química , Isoindóis , Espectroscopia de Ressonância Magnética , Metilação , Modelos Moleculares , Teoria Quântica
8.
Artigo em Inglês | MEDLINE | ID: mdl-23353694

RESUMO

The novel phthalonitrile containing azine segment and its corresponding tetra aldazine substituted metal free- and metallo-phthalocyanines (Zn(II) and Ni(II)) were synthesized and characterized by IR, (1)H NMR, Mass, UV-Vis spectroscopy and elemental analysis and addition to these techniques for substituted phthalonitrile (13)C NMR have been used. In addition, dc and ac electrical properties of the films of these novel phthalocyanines were investigated as a function of temperature (295-523 K) and frequency (40-10(5)Hz). Activation energy values of the films of the phthalocyanines were calculated from straight portions of the Arrhenius plot (lnσ(dc)-1/T curves) as 0.70 eV, 0.93 eV and 0.91 eV for the films of metal free, nickel- and zinc-phthalocyanines, respectively. From impedance spectroscopy measurements, it is observed that bulk resistance decreases with increasing temperature indicating semiconductor property.


Assuntos
Indóis/química , Níquel/química , Nitrilas/química , Compostos Organometálicos/química , Tioridazina/química , Espectroscopia Dielétrica , Condutividade Elétrica , Indóis/síntese química , Isoindóis , Nitrilas/síntese química , Compostos Organometálicos/síntese química , Semicondutores , Análise Espectral , Tioridazina/síntese química , Compostos de Zinco
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