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1.
J Pharm Biomed Anal ; 240: 115947, 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38181557

RESUMO

Huangqi Liuyi Decoction, a famous classical Chinese prescription, shows significant curative effect on diabetes and its complications, in which calycosin-7-glucoside, liquiritin and glycyrrhizic acid are the main components that playing these mentioned pharmacological activity, under the synergistic action of various other ingredients in the decoction. However, there are significant differences in the content of active compounds in Chinese medicinal materials, which mainly due to origin, picking seasons, and processing methods. Hence, the accurate content of the glycosides is the prerequisite for ensuring the pharmacological efficacy. Aiming at establishing an efficient extraction and determination method for accurate quantitative analysis of calycosin-7-glucoside, liquiritin and glycyrrhizic acid in Huangqi Liuyi Decoction, an on line solid-phase extraction-high-performance liquid chromatography method was developed, using a homemade bio-based monolithic adsorbent. The bio-based adsorbent was prepared in a stainless steel tube, using bio-monomers of methyleugenol and S-allyl-L-cysteine, which effectively reduced the dependence of the polymer field on non-renewable fossil resources and reduced carbon emissions. Furthermore, the prepared adsorbent owned abundant chemical groups, which can produce interactions of hydrogen bond, dipole-dipole, π-π and hydrophobic force with the target glycosides, thus improving the specific recognition ability of the adsorbent. The experiments were carried out on an LC-3000 HPLC instrument with a six-way valve. Methodology validation indicates that the recovery is in the range of 97.0%-103.4% with the RSD in the range of 1.6%-4.0%, due to the specific selectivity of the bio-based monolithic adsorbent for these three glycosides, and good matrix-removal ability for Huangqi Liuyi decoction. The limit of detection is 0.17, 0.50 and 0.33 µg/mL for calycosin-7-glucoside, liquiritin and glycyrrhizic acid, respectively, and the limit of quantitation is 0.50, 1.50 and 1.00 µg/mL, respectively, with the linear range of 2-200 µg/mL for calycosin-7-glucoside, and 5-500 µg/mL for liquiritin and glycyrrhizic acid. The present work provided a simple and efficient method for the extraction and determination of glycosides in complex medicinal plants.


Assuntos
Astragalus propinquus , Medicamentos de Ervas Chinesas , Glicosídeos , Polímeros/análise , Ácido Glicirrízico , Medicamentos de Ervas Chinesas/química , Glucosídeos/análise , Cromatografia Líquida de Alta Pressão/métodos
2.
J Sep Sci ; 47(2): e2300802, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38286730

RESUMO

Polyethylene glycol (PEG) is one of the most commonly used polymers in drug delivery systems. The investigation of the pharmacokinetic behavior of PEG is important for revealing the toxicity and efficiency of PEG-related Nano-drug delivery systems. A high through-put and selective ultra-high-performance liquid chromatography with tandem mass spectrometry (UHPLC-MS/MS) method coupled with collision-induced dissociation (CID) in source technique was developed and validated to determine PEG1K polymers in cellular samples in this study. The countless precursor ions of PEG1K are dissociated in the source to generate numerous product ions which have different numbers of subunits. The transition of [M+H]+ precursor ions → product ions at m/z 177.1 (four subunits)→89.1 (two subunits) was selected to determine PEG1K due to its high sensitivity. The UHPLC-MS/MS method coupled with CID in the source showed good linearity over the range of 0.1-10 µg/mL. Intra-day and inter-day accuracies and precisions of the assay were all within ± 12.39%. The assay was successfully applied to a cellular pharmacokinetic study of PEG1K in human breast cancer cells. The cytotoxicity of PEG1K polymers was also studied and the results indicated that the cytotoxicity of PEG1K was not significant in the range of 5-1200 µg/mL.


Assuntos
Polímeros , Espectrometria de Massas em Tandem , Humanos , Espectrometria de Massas em Tandem/métodos , Cromatografia Líquida de Alta Pressão/métodos , Polímeros/toxicidade , Polímeros/análise , Polietilenoglicóis/química , Íons
3.
Adv Mater ; 35(35): e2301242, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37370137

RESUMO

Synthetic hydrogels often lack the load-bearing capacity and mechanical properties of native biopolymers found in tissue, such as cartilage. In natural tissues, toughness is often imparted via the combination of fibrous noncovalent self-assembly with key covalent bond formation. This controlled combination of supramolecular and covalent interactions remains difficult to engineer, yet can provide a clear strategy for advanced biomaterials. Here, a synthetic supramolecular/covalent strategy is investigated for creating a tough hydrogel that embodies the hierarchical fibrous architecture of the extracellular matrix (ECM). A benzene-1,3,5-tricarboxamide (BTA) hydrogelator is developed with synthetically addressable norbornene handles that self-assembles to form a and viscoelastic hydrogel. Inspired by collagen's covalent cross-linking of fibrils, the mechanical properties are reinforced by covalent intra- and interfiber cross-links. At over 90% water, the hydrogels withstand up to 550% tensile strain, 90% compressive strain, and dissipated energy with recoverable hysteresis. The hydrogels are shear-thinning, can be 3D bioprinted with good shape fidelity, and can be toughened via covalent cross-linking. These materials enable the bioprinting of human mesenchymal stromal cell (hMSC) spheroids and subsequent differentiation into chondrogenic tissue. Collectively, these findings highlight the power of covalent reinforcement of supramolecular fibers, offering a strategy for the bottom-up design of dynamic, yet tough, hydrogels and bioinks.


Assuntos
Bioimpressão , Hidrogéis , Humanos , Hidrogéis/química , Biomimética , Matriz Extracelular/química , Polímeros/análise , Engenharia Tecidual , Impressão Tridimensional
4.
Food Chem ; 417: 135852, 2023 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-36924723

RESUMO

Microwavable plastic food containers can be a source of toxic substances. Plastic materials such as polypropylene polymers are typically employed as safe materials in food packaging, but recent research demonstrates the migration of plastic substances or their by-products to food simulants, to foodstuff, and, more recently, to the human body through food consumption. However, a thorough evaluation of foodstuff in food contact materials under cooking conditions has not yet been undertaken. Here we show for the first time that plastic migrants present in food contact materials can react with natural food components resulting in a compound that combines a UV-photoinitiator (2-hydroxy-2-methyl-1-phenylpropan-1-one) with maltose from potato starch; this has been identified after cooking potatoes in microwavable plastic food containers. Additionally, polypropylene glycol substances have been found to transfer into food through microwave cooking. Identifying these substances formed in situ requires state-of-the-art high-resolution mass spectrometry instrumentation and metabolomics-based strategies.


Assuntos
Plásticos , Polipropilenos , Humanos , Plásticos/análise , Cromatografia Gasosa-Espectrometria de Massas/métodos , Polímeros/análise , Embalagem de Alimentos , Culinária , Contaminação de Alimentos/análise
5.
Food Chem ; 413: 135605, 2023 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-36787666

RESUMO

The contamination of polycyclic aromatic hydrocarbons (PAHs) in edible oil is a health threat. Thus, trace analysis of PAHs is of high necessity. Based on the efficient adsorption of PAHs on Zn5 metal cluster, a Zn5 functionalized copolymer monolithic column was rationally designed for pipette tip micro-solid phase extraction (µ-SPE). The modified Zn5 improved the adsorption selectivity and capacity of the monolith for naphthalene, phenanthrene, fluoranthene and pyrene. Chemical doping and copolymerization stabilized the monolith with a long life. Under optimal extraction conditions, a µ-SPE-high performance liquid chromatography with ultraviolet detector method was established for the detection of 4 PAHs in edible oils. The method yielded detection ranges of 0.15-250 µg L-1 (R2 > 0.997), detection limits of 0.050-1.5 µg L-1, satisfactory recoveries (86.3-101.5 %), and high precisions (RSDs < 7.9 %). The results indicated that the Zn5 functionalized copolymer monolithic column was an ideal separation medium for the detection of PAHs residues in edible oils.


Assuntos
Hidrocarbonetos Policíclicos Aromáticos , Hidrocarbonetos Policíclicos Aromáticos/análise , Limite de Detecção , Extração em Fase Sólida/métodos , Óleos , Cromatografia Líquida de Alta Pressão , Polímeros/análise , Zinco
6.
Food Chem ; 401: 134125, 2023 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-36096004

RESUMO

The influence and its mechanism of ultrasound on acetaldehyde/glyoxylic acid competing bridged the polymerization coloration of flavan-3-ols in model wine solution were investigated by high-performance liquid chromatography-mass spectrometry (HPLC-MS) and kinetics and thermodynamic model. The results indicate that ultrasound could significantly accelerate the polymerization coloration and further modify wine color. In addition, the polymerization reaction conformed first-order reaction model, and the reaction rate constant (k) values were markedly increased by ultrasound, accelerating the coloration reaction, especially in the model wine containing glyoxylic acid. Besides, the polymerization processing was non-spontaneous and endothermic according to the thermodynamic analysis. In conclusion, ultrasound was indeed conducive to accelerate glyoxylic acid/acetaldehyde-bridged the polymerization of flavan-3-ols and further effect the wine color, which could provide a theoretical basis for the scientific analysis of the mechanism of ultrasound modifying wine color.


Assuntos
Vinho , Vinho/análise , Acetaldeído/análise , Glioxilatos/química , Cromatografia Líquida de Alta Pressão , Polifenóis/análise , Polímeros/análise , Flavonoides/análise
7.
Sci Total Environ ; 857(Pt 2): 159318, 2023 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-36220465

RESUMO

Plastic food packaging represents 40 % of the plastic production worldwide and belongs to the 10 most commonly found items in aquatic environments. They are characterized by high additives contents with >4000 formulations available on the market. Thus they can release their constitutive chemicals (i.e. additives) into the surrounding environment, contributing to chemical pollution in aquatic systems and to contamination of marine organism up to the point of questioning the health of the consumer. In this context, the chemical and toxicological profiles of two types of polypropylene (PP) and polylactic acid (PLA) food packaging were investigated, using in vitro bioassays and target gas chromatography mass spectrometry analyses. Plastic additives quantification was performed both on the raw materials, and on the material leachates after 5 days of lixiviation in filtered natural seawater. The results showed that all samples (raw materials and leachates) contained additive compounds (e.g. phthalates plasticizers, phosphorous flame retardants, antioxidants and UV-stabilizers). Differences in the number and concentration of additives between polymers and suppliers were also pointed out, indicating that the chemical signature cannot be generalized to a polymer and is rather product dependent. Nevertheless, no significant toxic effects was observed upon exposure to the leachates in two short-term bioassays targeting baseline toxicity (Microtox® test) and Pacific oyster Crassostrea gigas fertilization success and embryo-larval development. Overall, this study demonstrates that both petrochemical and bio-based food containers contain harmful additives and that it is not possible to predict material toxicity solely based on chemical analysis. Additionally, it highlights the complexity to assess and comprehend the additive content of plastic packaging due to the variability of their composition, suggesting that more transparency in polymer formulations is required to properly address the risk associated with such materials during their use and end of life.


Assuntos
Polipropilenos , Poluentes Químicos da Água , Polipropilenos/análise , Embalagem de Alimentos , Poluentes Químicos da Água/análise , Plásticos/análise , Poliésteres/análise , Polímeros/análise , Bioensaio , Medição de Risco
8.
Food Chem ; 399: 133918, 2023 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-35994858

RESUMO

A core-shell magnetic sulfonatocalix[6]arene covalently cross-linked polymer was proposed as a magnetic adsorbent, combined with ultra-high performance liquid chromatography tandem mass spectrometry (UHPLC-MS/MS) for the enrichment and determination of epoxy derivatives in canned foods. The adsorbent has high density of host-guest recognition functional groups, abundant binding sites and suitable cavity size, showing good extraction performance for epoxy derivatives. Quantum chemical simulation calculations provedmultiple interaction forces in the adsorption process. Theextractionparameterswere investigated. Under optimized experimental conditions, 13 kinds of target analytes showed low detection limits (0.0072-0.023 ng/g) and good precisions (RSDs of 0.8 %-9.4 %). This method has been successfully applied to the simultaneous determination of 13 kinds of epoxy derivatives in different food samples including canned beverage, fish, meat, and milk powder. Satisfactory recoveries (74.9 %-118 %) were obtained. The results showed the potential application prospects in the enrichment and detection of hazardous substances in food.


Assuntos
Éter , Espectrometria de Massas em Tandem , Animais , Cromatografia Líquida de Alta Pressão/métodos , Alimentos em Conserva/análise , Glicerol , Éteres de Glicerila , Indicadores e Reagentes , Fenômenos Magnéticos , Polímeros/análise , Extração em Fase Sólida/métodos , Espectrometria de Massas em Tandem/métodos
9.
São Paulo; s.n; s.n; 2023. 107 p. tab, graf, ilus.
Tese em Português | LILACS | ID: biblio-1437843

RESUMO

Atualmente a agricultura ocupa um papel de extrema importância na conjuntura global e nacional e está inserida em um contexto de enormes desafios devido ao aumento da população mundial e maior demanda por alimentos. Ao mesmo tempo, é o setor mais afetado pelos impactos negativos das mudanças climáticas, que têm espalhado suas consequências de maneira cada vez mais frequente e intensa. Um dos principais efeitos é a alteração do regime de chuvas ao redor do globo, ocasionando estiagens intensas e duradouras, capazes de reduzir a produtividade de safras e comprometer a produção alimentícia. As abordagens atualmente existentes no mercado para mitigar as consequências negativas da escassez hídrica demandam alto investimento de implementação e manutenção, ou possuem um perfil ecotoxicológico insatisfatório. Polímeros de origem natural modificados quimicamente foram avaliados em termos de desempenho e capacidade de prover às plantas uma maior disponibilidade de água através de retenção hídrica. Os resultados alcançados demonstraram que os polímeros modificados com grupos iônicos foram capazes de promover um melhor gerenciamento hídrico no microambiente ao redor de sementes e entregar ganhos de produtividade a lavouras de soja. O mecanismo de ação da tecnologia estudada foi elucidado através de ensaios de determinação de capacidade de campo, análise de elipsometria, microscopia de força atômica, ensaios de germinação de soja sob estresse hídrico e implementação de áreas de soja a céu aberto a partir da aplicação em tratamento de sementes e sulco de plantio. As interações intra e intermoleculares entre as partículas de solo, moléculas de polímero e de água se mostraram ponto chave para a mudança de patamar de desempenho de polímeros naturais modificados utilizados na agricultura, quando comparados com os grupos controle. A tecnologia aqui estudada é, portanto, recomendada para utilização na agricultura, com capacidade de potencializar o efeito de tecnologias dependentes de água, resultando em maior produtividade na colheita


Nowadays agriculture occupies an extremely important role both in the global and national scenarios. Its included in a very challenging context due to the forecast of increased world population and consequent higher demand for food. At the same time, it is the most affected economic sector by the climate change effects, which have been causing frequent and harsh impacts. One of the main effects is the change in the rainfall pattern worldwide, which causes severe and long-lasting droughts, responsible for causing crops to fail and therefore putting food production at risk. The current available mitigation measures to address hydric scarcity require a huge investment for implementation and maintenance or do not present a satisfactory and safe ecotoxicological profile. Chemically modified natural polymers have been evaluated in terms of performance and ability to provide the plants with higher water availability through hydric retention. The results obtained show that such ionic group modified polymers are able to promote better water management in a given microenvironment surrounding the seeds and ultimately delivery a higher yield to soy crops. The technology's mode of action has been elucidated through field capacity determination trials, ellipsometry, atomic force microscopy, soy germination trials under hydric stress and, finally, implementation of soy areas under actual field conditions by applying the polymers via seed treatment and in-furrow methods. Both intra- and intermolecular interaction between soil particles, polymer and water molecules have been proven as key to understanding the agricultural performance improvement of the modified polymers when compared to the control. The technology is recommended for agricultural applications due to its ability to boost the effect of water-dependent technologies, promoting higher yields


Assuntos
Polímeros/análise , Desidratação/complicações , Agricultura/classificação , Polissacarídeos/efeitos adversos , Solo , Glycine max/crescimento & desenvolvimento , Água , Eficiência/classificação , Alimentos/classificação
10.
Pathol Oncol Res ; 28: 1610739, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36567980

RESUMO

Saliva is a noninvasive biofluid that contains the metabolic signature of severe periodontitis (SP, Stage IV and Grade C). Conductive polymer spray ionization mass spectrometry (CPSI-MS) was used to record a wide range of metabolites within a few seconds, making this technique a promising point-of-care method for the early detection of SP (Stage IV and Grade C). Saliva samples from 31 volunteers, consisting of 16 healthy controls (HC) and 15 patients with SP (Stage IV and Grade C), were collected to identify dysregulated metabolites. Twenty metabolites were screened out, including seven amino acids. Moreover, the results showed that amino acid metabolism is closely related to the development of periodontitis. The present study further confirmed that salivary metabolites in the oral cavity were significantly altered after plaque removal. These results suggest that the combination of CPSI-MS is a feasible tool for preclinical screening of SP (Stage IV and Grade C).


Assuntos
Periodontite , Polímeros , Humanos , Polímeros/análise , Polímeros/metabolismo , Periodontite/metabolismo , Espectrometria de Massas/métodos , Saliva/química
11.
Mar Environ Res ; 179: 105676, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35803050

RESUMO

The ingestion of anthropogenic plastic debris by marine wildlife is widespread in the Mediterranean Sea. The endangered status (in the IUCN Red List) of Loggerhead turtle (Caretta caretta, Linnaeus, 1758) is a consequence of its vulnerability. In this study, macro-/meso-plastics (5-170 mm) collected from faeces of twelve loggerhead turtles rescued (live) in the Aeolian Archipelago (Southern Tyrrhenian Sea, Italy) were analyzed by size, weight, shape, color and polymer type through Attenuated Total Reflectance Fourier-Transform Infrared Spectroscopy (ATR-FTIR). The defecation rate during hospitalization (7-14 days) varied among turtles (from 0.08 to 0.58). The mean number of plastic expulsions (2.7 ± 1.8 items for turtle) was higher during the 5th day of hospitalization (Kruskal-Wallis test, P = 0.01). However, the mean number of plastic-like items defecated during the common days of hospitalization did not vary among turtles (Kruskal-Wallis test, P > 0.05). All turtles were found to have ingested plastic. A total of 114 debris items were recovered from their faeces, 113 of which were identified as plastic. Their color was mostly white-transparent (64.9%) and light (19.3%). Shape was mainly fragments (52.6%), sheets (38.6%), followed by nylon, net-fragments, elastic plastic, foamed plastic and industrial granules (8.8%). Meso-plastics (5-25 mm) represented 72% of the total number of debris and were found more frequently in turtle with Curved Carapace Length (CCL) ≤ 60 cm (CCL = 30-60 cm, n = 5) than those with CCL >60 cm (CCL = 60-71 cm, n = 7). Plastic items were composed mainly of polyethylene (48.2%) and polypropylene (34.2%). Polypropylene (R2 = 0.95, P < 0.001) and polyisoprene (R2 = 0.45, P = 0.017) were more common in meso-plastics while polyethylene (R2 = 0.44, P < 0.01) in macro-plastics. Finally, high-density polyethylene, polyvinyl chloride, polyamide and polyurethane were also found in some turtles. This study reveals high spreads of plastic contamination in faeces of both turtles with CCL ≤60 cm and CCL >60 cm, particularly vulnerable to the increasing quantity of floating plastic into their foraging sites highlighting the need of further research to associate debris ingestion with turtle diet and their size.


Assuntos
Tartarugas , Poluentes da Água , Animais , Conteúdo Gastrointestinal/química , Plásticos/análise , Polietileno/análise , Polímeros/análise , Polipropilenos/análise , Espectroscopia de Infravermelho com Transformada de Fourier , Poluentes da Água/análise
12.
Acta Chim Slov ; 69(2): 322-330, 2022 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-35861066

RESUMO

The quality of edible oils is significantly affected by autoxidation of lipids, which alters their flavor and nutritional quality through production of toxic materials like aldehydes (an important class of oil deterioration markers). Herein, an amino-silica nanospheres/polypyrrole (ASNS/PPy) nanocomposite sorbent was synthesized and used as the fiber coating for headspace solid-phase microextraction (HS-SPME) of aldehydes in edible oils, followed by gas chromatography (GC) separation and determination. Amino-silica nanoparticles were prepared by an amended Stöber method and composited with polypyrrole during its electropolymerization on the surface of a platinized stainless-steel fiber. The synergy between in-situ electropolymerization and rough surface of the platinized metal substrate created a durable fiber coating with unique uniformity, cohesiveness, and adsorption properties. The synthesized nanocomposite was characterized using Fourier transform infrared spectroscopy and scanning electron microscopy techniques. The performance of the prepared fiber was optimized by investigating the affecting variables including extraction temperature and time, stirring rate, and desorption conditions. The obtained limits of detection for hexanal and heptanal in sunflower oil were 0.005-0.009 µg mL-1. The prepared fiber exhibited excellent repeatability and reproducibility with the intra-fiber and inter-fiber relative standard deviations in the ranges of 3.9-8.8% and 7.3-15.1%, respectively. The proposed HS-SPME-GC strategy was successfully applied for the analysis of aldehydes in commercial edible oil samples.


Assuntos
Nanosferas , Polímeros , Aldeídos , Nanosferas/análise , Óleos , Polímeros/análise , Polímeros/química , Pirróis/análise , Pirróis/química , Reprodutibilidade dos Testes , Dióxido de Silício/química , Microextração em Fase Sólida/métodos
13.
Molecules ; 27(10)2022 May 19.
Artigo em Inglês | MEDLINE | ID: mdl-35630728

RESUMO

A new solid-phase extraction (SPE) method for the extraction, enrichment, and analysis of eight polybrominated diphenyl ethers (PBDEs) in water was developed. The current approach involves using a cross-linked starch-based polymer as an extraction adsorbent and determining the PBDE analytes of interest using gas chromatography-mass spectrometry in negative chemical ionization mode (GC-NCI-MS). The starch-based polymer was synthesized by the reaction of soluble starch with 4,4'-methylene-bis-phenyldiisocyanate as a cross-linking agent in dry dimethylformamide. Various parameters impacting extraction efficiencies, such as adsorbent quantity, sample volumes, elution solvents and volumes, and methanol content, were carefully optimized. The 500 mg of starch-based polymer as an adsorbent used to extract 1000 mL of spiked water, presented high extraction recoveries of eight PBDEs. The linearity of the extraction process was investigated in the range of 1-200 ng L-1 for BDE-28, 47, 99, 100, and 5-200 ng L-1 for BDE-153, 154, 183, and 209, with coefficients of determination (r2) exceeding 0.990 for all PBDEs. The limits of detection (LODs) ranged from 0.06 to 1.42 ng L-1 (S/N = 3) and the relative standard deviation values (RSD) were between 3.6 and 9.5 percent (n = 5) under optimum conditions. The method was successfully used to analyze river and lake water samples, where it exhibited acceptable recovery values of 71.3 to 104.2%. Considering the excellent analytical performance and comparative cost advantage, we recommend the developed starch-based SPE method for routine extraction and analysis of PBDEs in water media.


Assuntos
Éteres Difenil Halogenados , Poliuretanos , Cromatografia Gasosa-Espectrometria de Massas/métodos , Éteres Difenil Halogenados/análise , Polímeros/análise , Extração em Fase Sólida/métodos , Amido , Água
14.
Water Res ; 220: 118645, 2022 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-35635914

RESUMO

Microplastics (MPLs) are emerging persistent pollutants affecting drinking water systems, and different studies have reported their presence in tap water. However, most of the work has a focus on particles in the 100-5 µm range. Here, a workflow to identify and quantify polymers of micro and nanoplastics (MNPLs), with sizes from 0.7 to 20 µm in tap water, is presented. The analytical method consisted of water fractionated filtration followed by toluene ultrasonic-assisted extraction and size-exclusion chromatography, using an advanced polymer chromatography column coupled to high-resolution mass spectrometry with atmospheric pressure photoionization source with negative and positive ionization conditions (HPLC(APC)-APPI(±)-HRMS) and normal phase chromatography HILIC LUNA® column and electrospray ionisation source in positive and negative mode (HPLC(HILIC)-ESI(±)-HRMS). The acquisition was performed in full scan mode, and the subsequent tentative identification of MNPLs polymers has been based on increasing the confirmation level, including the characterisation of monomers by using Kendrick Mass Defect (KMD) analysis, and confirmation and quantification using standards. This approach was applied to assess MNPLs in tap water samples of the Barcelona Metropolitan Area (BMA), that were collected from August to October 2020 from home taps of volunteers distributed in the 42 postal codes of the BMA. Polyethylene (PE), polypropylene (PP), polyisoprene (PI), polybutadiene (PBD), polystyrene (PS), polyamide (PA), and polydimethylsiloxanes (PDMS) were identified. PE, PP, and PA were the most highly detected polymers, and PI and PBD were found at the highest concentrations (9,143 and 1,897 ng/L, respectively). A principal component analysis (PCA) was conducted to assess differences in MNPLs occurrence in drinking water, that was provided from the two drinking water treatment plants (DWTPs) suppliers. Results showed that no significant differences (at 95% confidence level) were established between the drinking water supplies to the different areas of the BMA.


Assuntos
Água Potável , Poluentes Químicos da Água , Cromatografia Líquida de Alta Pressão , Água Potável/análise , Humanos , Plásticos/análise , Polietileno/análise , Polímeros/análise , Poluentes Químicos da Água/análise
15.
Biomol NMR Assign ; 16(2): 231-236, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-35482172

RESUMO

The ability to interact and adapt to the surrounding environment is vital for bacteria that colonise various niches and organisms. One strategy developed by Gram-negative bacteria is to secrete exoprotein substrates via the type II secretion system (T2SS). The T2SS is a proteinaceous complex spanning the bacterial envelope that translocates folded proteins such as toxins and enzymes from the periplasm to the extracellular milieu. In the T2SS, a cytoplasmic ATPase elongates in the periplasm the pseudopilus, a non-covalent polymer composed of protein subunits named pseudopilins, and anchored in the inner membrane by a transmembrane helix. The pseudopilus polymerisation is coupled to the secretion of substrates. The T2SS of Dickeya dadantii secretes more than 15 substrates, essentially plant cell wall degrading enzymes. In D. dadantii, the major pseudopilin or the major subunit of the pseudopilus is called OutG. To better understand the mechanism of secretion of these numerous substrates via the pseudopilus, we have been studying the structure of OutG by NMR. Here, as the first part of this study, we report the 1H, 15N and 13C backbone and sidechain chemical shift assignment of the periplasmic domain of OutG and its NMR derived secondary structure.


Assuntos
Sistemas de Secreção Tipo II , Adenosina Trifosfatases/metabolismo , Proteínas de Bactérias/química , Dickeya , Ressonância Magnética Nuclear Biomolecular , Periplasma/metabolismo , Polímeros/análise , Polímeros/metabolismo , Ligação Proteica , Subunidades Proteicas/metabolismo , Sistemas de Secreção Tipo II/química
16.
Anal Chim Acta ; 1199: 339570, 2022 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-35227380

RESUMO

An effective extraction procedure based dispersive solid phase extraction was developed for the extraction of different pesticides (dimethoate, imidacloprid, pirimicarb, carbaryl, fenitrothion, hexythiazox, and phosalone) from milk samples. The analytes were determined by high performance liquid chromatography-tandem mass spectrometry. In this method, an organic polymer (polystyrene) was dissolved in a water-miscible organic solvent (tetrahydrofuran) and it was injected into the aqueous phase obtained from milk sample after deprotonation. By this action the sorbent (polymer) was precipitated and dispersed in the solution as tiny particles. By doing so, the pesticides were adsorbed onto the sorbent. After that, the sorbent was separated by centrifugation and the adsorbed analytes were eluted by tetrabutylammonium chloride: dichloroacetic acid deep eutectic solvent. After optimization, the method validation was followed according to Food and Drug Administration and International Research Council guidelines and the results showed that wide linear ranges (0.93-500 ng/mL) and low limits of detection (0.09-0.27 ng/mL) and quantification (0.31-0.93 ng/mL) were obtained. Extraction recoveries and extraction and enrichment factors were in the ranges of 81-94% and 162-188, respectively. Relative standard deviations were less than 9% for intra- (n = 6) and inter-day (n = 6) precisions at three concentration of 2, 5, and 25 ng mL-1 of each analyte. The developed method was successfully applied to twenty cow milk samples for determination of the pesticides.


Assuntos
Microextração em Fase Líquida , Praguicidas , Animais , Cromatografia Líquida de Alta Pressão , Solventes Eutéticos Profundos , Microextração em Fase Líquida/métodos , Leite/química , Praguicidas/análise , Polímeros/análise , Extração em Fase Sólida/métodos , Solventes/química , Espectrometria de Massas em Tandem
17.
J Complement Integr Med ; 19(3): 763-769, 2022 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-33946137

RESUMO

OBJECTIVES: 1-Deoxynojirimycin (1-DNJ), the main active component found in Morus nigra (black mulberry) is reported to be effective in controlling diabetes. We have evaluated the effect of hydro-alcoholic extract of M. nigra leaves on the fasting blood glucose (FBS) and hemoglobin A1c% (HbA1c%) in diabetic patients. Furthermore, we compared the interaction of 1-DNJ and glucose molecules with the alpha-glucosidase enzyme, which has a critical role in the lysis of glucose-based polymers in human cells. METHODS: 4% hydro-alcoholic extract was prepared from black mulberry leaves. Patients in treatment (n=50) and control (n=50) groups received 3 mL extract or placebo in water, respectively, and three times a day. Fasting blood glucose and HbA1c% were evaluated before and after three months of evaluation. Potential binding sites of 1-DNJ or glucose on the enzyme glucosidase found by docking study. Docking scores were obtained using an energy minimization method by Molegro Virtual Docker software. The Mean ± SD of each variable was compared between groups at the 95% significant level. RESULTS: Age mean ± SD was equal to 54.79 ± 9.203 (38-69) years. There was no significant difference between intervention and placebo groups considering FBS (p=0.633) but was for HbA1c% (p=0.0011), before treatment. After three months, both FBS and HbA1c% were significantly reduced in patients under mulberry leaves extract-treatment. FBS changed was from 182.23 ± 38.65 to 161.23 ± 22.14 mg/dL in treatment group (p<0.001) and from 178.45 ± 39.46 to 166.23 ± 29.64 mg/dL in control group (p<0.001). HbA1c was changed from 7.23 ± 0.25 to 6.13 ± 0.61% in treatment group (p<0.001) and from 7.65 ± 0.85 to 7.12 ± 0.33% in control group (p=0.854). Docking results showed that 1-DNJ binds more efficiently, and with a significant score than glucose, to human alpha-glucosidase. CONCLUSIONS: This clinical trial and virtual analysis showed that a hydro-alcoholic extract of black mulberry (M. nigra) leaf may be efficient in reducing the blood glucose and HbA1c% in diabetic patients. Furthermore, docking studies propose a competitive and allosteric regulation for herbal ingredients. Drug-development could be based on the presented idea in this report.


Assuntos
Diabetes Mellitus , Morus , 1-Desoxinojirimicina/farmacologia , 1-Desoxinojirimicina/uso terapêutico , Glicemia/análise , Jejum , Glucosidases/análise , Hemoglobinas Glicadas , Humanos , Morus/química , Extratos Vegetais/análise , Extratos Vegetais/farmacologia , Extratos Vegetais/uso terapêutico , Folhas de Planta/química , Polímeros/análise , Água/análise , alfa-Glucosidases
18.
Braz. J. Pharm. Sci. (Online) ; 58: e191023, 2022. tab, graf
Artigo em Inglês | LILACS | ID: biblio-1403698

RESUMO

Abstract In the work the andrographolide (AG)-solid dispersions (SDs) were prepared by the spray-drying method, using polyethylene glycol 8000 (PEG8000), Poloxamer188, polyvinylpyrrolidone K30 (PVPK30), Soluplus® as carrier materials. The effect of different polymers as carrier materials on the properties of the AG-SDs were studied. The results showed obvious differences in intermolecular interaction, thermal stability, drug state, powder properties, dissolution behavior, and so on of AG-SDs prepared using different polymers as carrier materials. AG-PEG8000-SD was a partial-crystalline and partial-amorphous powder with smaller surface area and pore volume, but it was easy to wetting and did not swell in contact with dissolved medium. AG-Soluplus®-SD was completely amorphous powder with larger specific surface area and pore volume, but it swelled in contact with water. Therefore, the dissolution profile of AG in AG-PEG8000-SD was similar to that in AG-Soluplus®-SD. Soluplus® and PEG8000 were suitable polymers to design AG-SDs, considering both physicochemical properties and dissolution behaviors. The results of this reseach showed that when selecting carrier materials for SD, we should not only consider the state of drugs in SD and the powder properties of SD, but also consider whether there is swelling when the carrier materials are in contact with the dissolution medium.


Assuntos
Polietilenoglicóis/efeitos adversos , Dissolução , Métodos , Polímeros/análise , Preparações Farmacêuticas/análise , Água , Secagem por Atomização
19.
ACS Appl Mater Interfaces ; 13(47): 55978-55987, 2021 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-34735134

RESUMO

The pollution of water environments is a worldwide concern. Not only marine pollution by plastic litter, including microplastics, but also the spillage of water-soluble synthetic polymers in wastewater have recently gained increasing attention due to their potential risks to soil and water environments. However, conventional methods to identify polymers dissolved in water are laborious and time-consuming. Here, we propose a simple approach to identify synthetic polymers dissolved in water using a peptide-based molecular sensor with a fluorophore unit. Supervised machine learning of multiple fluorescence signals from the sensor, which specifically or nonspecifically interacted with the polymers, was applied for polymer classification as a proof of principle demonstration. Aqueous solutions containing different polymers or multiple polymer species with different mixture ratios were identified successfully. We found that fluorophore-introduced biomolecular sensors have great potential to provide discriminative information regarding water-soluble polymers. Our approach based on the discrimination of multiple optical signals of water-soluble polymers from peptide-based molecular sensors through machine learning will be applicable to next-generation sensing systems for polymers in wastewater or natural environments.


Assuntos
Peptídeos/química , Polímeros/análise , Corantes Fluorescentes/química , Aprendizado de Máquina , Estrutura Molecular , Tamanho da Partícula , Peptídeos/síntese química , Polímeros/síntese química , Solubilidade , Espectrometria de Fluorescência , Propriedades de Superfície , Água/química
20.
Toxicol Ind Health ; 37(9): 573-584, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34399648

RESUMO

3-Dimensional (3D) printing and bioprinting are the new technologies. In 3D printing, synthetic polymers such as acrylonitrile, butadiene, and styrene, polylactic acid, nylon, and some metals are used as feedstocks. During 3D printing, volatile organic compounds (VOCs) and nanoparticles can be released. In the bioprinting process, natural polymers are most commonly used. All of these materials have direct and indirect toxic effects in exposed people. Therefore, the aim of this study was to provide a comprehensive review of toxicity risks due to occupational exposure to pollutants in the 3D printing and bioprinting industries. The Cochrane review method was used as a guideline for systematic review. Articles were searched in the databases including PubMed, Scopus, Web of Science, and Google Scholar. This systematic review showed that VOCs and ultra-fine particles are often released in fused deposition modeling and selective laser sintering, respectively. Asthma, chronic obstructive pulmonary disease, allergic rhinitis, and DNA damage were observed in occupational exposure to synthetic polymers. Metal nanoparticles can induce adverse health effects on the respiratory and nervous systems. This study emphasized the need to further study the toxicity of 3D printing and bioprinting-induced air pollutants. Also, consideration of safety and health principles is necessary in 3D printing and bioprinting workplaces.


Assuntos
Bioimpressão/métodos , Doenças Neuromusculares/induzido quimicamente , Exposição Ocupacional/efeitos adversos , Exposição Ocupacional/análise , Impressão Tridimensional , Doenças Respiratórias/induzido quimicamente , Poluentes Atmosféricos/efeitos adversos , Poluentes Atmosféricos/análise , Dano ao DNA/efeitos dos fármacos , Humanos , Mediadores da Inflamação/metabolismo , Material Particulado/efeitos adversos , Material Particulado/análise , Polímeros/efeitos adversos , Polímeros/análise
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