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1.
Mar Pollut Bull ; 151: 110868, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-32056648

RESUMO

This study aims to determine the degradation of plastic polypropylene (PP) and identify the presence of microplastic in sediments and seawater along the Tambak Lorok coastal area. The study was conducted by collecting samples from the sea surface area, at 50 cm and 170 cm depths, while seawater and sediments were collected from six stations. The results showed an early stage of degradation because of abiotic factors. The surface morphology of plastic changed, indicating the disorientation of the plastic. Furthermore, the results demonstrated that organic carbon decreased by 3.15%, 6.67%, and 16.76% for the PP applied on surface water, at 50 cm depth and at 170 cm depth, respectively. From six stations, PP microplastic was the dominant type, where microplastic in sediment was bio-fouled fiber ranging in size from 255.23 to 1245.71 µm; however, in seawater, it was 7-111 particles/10 mL and ranged from 270.27 to 1279.12 µm in size.


Assuntos
Monitoramento Ambiental , Plásticos , Polipropilenos/química , Poluentes Químicos da Água/química , Sedimentos Geológicos , Indonésia , Microplásticos/química , Poluentes Químicos da Água/análise
2.
PLoS One ; 15(2): e0228566, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32040517

RESUMO

OBJECTIVE: Although sacrocolpopexy (SCP) can provide durable apical support, the use of mesh may give rise to various complications, including vaginal mesh erosion. The aim of this study was to identify the risk factors for vaginal mesh erosion after SCP in Korean women. METHODS: This retrospective cohort study included 363 women who underwent SCP with type 1 polypropylene mesh. They were evaluated at 1, 4, and 12 months after surgery and then annually thereafter with respect to anatomy and complications. Univariate and multivariate analyses using the Cox proportional hazard model were performed to identify the risk factors for mesh erosion. RESULTS: During the median 2-year follow-up period, vaginal mesh erosion was found in 29 women (8.0%). Among them, 19 (65.5%) required surgical correction. Estrogenic status was the only independent risk factor for mesh erosion. The risk for mesh erosion was 4.5 times higher in premenopausal women than in menopausal women not on estrogen replacement therapy (ERT) (95% confidence intervals [CI] 1.9-10.9, p<0.01). Menopausal women on ERT also had an increased risk, with a statistically marginal significance (hazard ratio 2.5, 95% CI 0.9-6.6; p = 0.07). CONCLUSIONS: Premenopausal or menopausal women on ERT are at high risk for mesh erosion after SCP with type 1 polypropylene mesh, and two-thirds of mesh erosion cases require reoperation. This information should be incorporated into patient counseling and treatment decisions.


Assuntos
Procedimentos Cirúrgicos em Ginecologia/efeitos adversos , Prolapso de Órgão Pélvico/cirurgia , Telas Cirúrgicas/efeitos adversos , Prolapso Uterino/cirurgia , Vagina/cirurgia , Idoso , Tomada de Decisões , Estrogênios/efeitos adversos , Feminino , Seguimentos , Humanos , Menopausa , Pessoa de Meia-Idade , Polipropilenos/química , Complicações Pós-Operatórias , Período Pós-Operatório , Pré-Menopausa , Reoperação , República da Coreia , Estudos Retrospectivos , Fatores de Risco , Fatores de Tempo
3.
Food Chem ; 313: 126164, 2020 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-31935662

RESUMO

A thermoseparating aqueous two-phase system (ATPS) based on ethylene oxide-propylene oxide (EOPO) copolymer and deep eutectic solvents (DES) was developed for the extraction and preliminary purification of polysaccharides in Camellia oleifera Abel. seed cake. DESs were used as the extraction media for obtaining the crude extract. The maximum extraction yield (Y) of polysaccharides was 152.37 mg/g in the crude extract. Then the crude polysaccharides were extracted and preliminary purified by EOPO/DES ATPS. The maximum extraction efficiency (E.E.) of polysaccharides was 86.91% in EOPO-rich phase by the first ATPS extraction. The EOPO-rich phase was separated and the polysaccharides were recovered by temperature-induced phase separation. The maximum recovery efficiency (R.E.) was 84.92% in aqueous phase by the second ATPS extraction. This thermoseparating ATPS possesses the merits of good environment-friendlies, simple operation, and easy recovery of components, which can be used as an efficient method for the extraction and separation of polysaccharides.


Assuntos
Camellia/química , Fracionamento Químico/métodos , Polissacarídeos/isolamento & purificação , Solventes/química , Manipulação de Alimentos/métodos , Polietilenos/química , Polipropilenos/química , Polissacarídeos/química , Sementes/química , Temperatura , Água
4.
Chemosphere ; 245: 125628, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31864060

RESUMO

Microplastics and Nitropolycyclic aromatic hydrocarbons (NPAHs) are two types of emerging pollutants that are strong potential threats to aquatic ecosystems and organisms. The adsorption of NPAHs on microplastics may explain the fate and effects of NPAHs in natural environments. In this study, the adsorption behavior of 9-Nitroanthrene (9-NAnt) on polyethylene (PE), polypropylene (PP) and polystyrene (PS) was investigated. Kinetic experiments revealed that 9-NAnt was inclined to be adsorbed onto microplastics, especially PE, which had a large adsorption amount of 734 µg g-1. A linear isothermal model better described the isothermal adsorption process for 9-NAnt, which indicated that a hydrophobic distribution may be the main adsorption mechanism in an aqueous solution. Water environment factors, such as the pH and ionic strength, had negligible effects on the adsorption for PE. In contrast, alkaline and high ionic strength conditions resulted in the inhibition of adsorption of PP and PS. In addition, the particle size of microplastics was negatively correlated with the log Kd of 9-NAnt, and the performance of transient aging treatments on microplastics reduced their affinity for 9-NAnt, due to the addition of oxygen-containing functional groups. Above all, hydrophobic and electrostatic processes were the main adsorption mechanisms between microplastics and 9-NAnt.


Assuntos
Antracenos/química , Microplásticos/química , Poluentes Químicos da Água/química , Adsorção , Ecossistema , Interações Hidrofóbicas e Hidrofílicas , Cinética , Plásticos/química , Polietileno/química , Polipropilenos/química , Poliestirenos/química , Eletricidade Estática , Poluentes Químicos da Água/análise
5.
Food Chem ; 309: 125792, 2020 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-31711806

RESUMO

Seven commercial samples, consisted of plastic bags, tetrabrik and box, were evaluated by gas chromatography-olfactometry-mass spectrometry (GC-O-MS) to find the compounds responsible for off-odors in different PP, PE, multilayer cardboard and paper materials used for food contact. Migration assays were carried out with Tenax as food simulant to analyze the food safety as well as to evaluate the odor intensity after migration assay. Forty six compounds with characteristic odors were directly found in the materials studied. The strongest odors identified were acetic, propanoic and butyric with vinegar and rancid odors and octanal, nonanal and decanal with fat/soup odors, all of them found in PP and PE samples. Trimethylbenzenes with solvent and oily odors as well as terpenes with weakly woody odors were found in cardboard and paper materials. After migration, all compounds were below the European Legislation limits and maximum migration values recommended by Cramer. However propanoic, acetic and butyric acid as well as aldehydes compounds, phenol and 1-octanol were detected by sniffers, after migration assay, with high modified frequency (between 50 and 78%), what could change the organoleptic properties of packaged food.


Assuntos
Embalagem de Alimentos , Odorantes/análise , Olfatometria/métodos , Polietileno/química , Polipropilenos/química , Aldeídos/análise , Contaminação de Alimentos/análise , Cromatografia Gasosa-Espectrometria de Massas , Papel , Fenóis/análise
6.
Ecotoxicol Environ Saf ; 186: 109746, 2019 Dec 30.
Artigo em Inglês | MEDLINE | ID: mdl-31606641

RESUMO

In this paper, polypropylene (PP) nanofibers were prepared using the melt forcespinning technology by a handmade device. Then, the surface of PP nanofibers was grafted through the high energy electron beams (EB) pre-irradiation method by acrylonitrile and methacrylic acid monomers with grafting percentage of 145.55%. The 92% of grafted cyano functional groups on nanofibers were converted to amidoxime groups, then modified by an alkaline solution. Characterization and surface morphology of nanofibers were investigated by Fourier Transform Infrared (FTIR) spectroscopy and scanning electron microscopy (SEM). The produced adsorbent was used to adsorb U(VI) ions from simulated seawater. The maximum adsorption was 83.24 mg/g in the optimal time of 60 min and optimal pH of 4. The optimum desorption efficiency was 80% in HCl 0.5 M. The kinetic data in optimum conditions showed that the adsorption followed an S-shaped kinetic model. The Adsorption equilibrium studies presented S-shape isotherm model that confirmed the adsorption occurs both on the adsorbent surface and in its pores The thermodynamic studies indicated spontaneous adsorption of uranyl ions and the higher efficiency adsorption at higher temperatures. The selectivity of adsorbent for metal ions followed the order V(V)>U(VI)>CO(II)>Ni(II)>Fe(II). These results shows that the prepared and modified nanofibers in this work can be considered as an effective and promising adsorbents for removal of uranium ions from seawater with high efficiency.


Assuntos
Recuperação e Remediação Ambiental/métodos , Nanofibras/química , Polipropilenos/química , Água do Mar/química , Urânio/química , Poluentes Químicos da Água/química , Adsorção , Concentração de Íons de Hidrogênio , Íons/química , Cinética , Espectroscopia de Infravermelho com Transformada de Fourier , Termodinâmica
7.
Mar Pollut Bull ; 145: 536-546, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31590821

RESUMO

Microplastic particles (<5 mm), which are an emerging threat, are commonly found in marine ecosystems worldwide. This study investigated the effect of different types of coastal land use on microplastic frequency and distribution on the coastline of Bandar Abbas city; this study used a large sample compared to that used in other studies conducted in this region. The average number of microplastics was determined as 3252 ±â€¯2766 microplastics/m2 (±SD). ATR FT-IR spectroscopy showed that the dominant microplastic particles are expanded polystyrene, polyethylene terephthalate, polypropylene, and polyethylene. Statistical analysis showed a significant difference in microplastic contamination levels between the urban and nonuse beaches. This shows that heavily urbanized areas and human activities have significant effects on the dispersion and frequency of microplastics in the coastal areas of Bandar Abbas. Periodical coast-based cleanup and studies on microplastic pollution and their fluxes by comprehensive sampling are mostly recommended for the Persian Gulf coastline.


Assuntos
/análise , Poluentes Químicos da Água/análise , Monitoramento Ambiental/métodos , Oceano Índico , Irã (Geográfico) , Polietileno/análise , Polietileno/química , Polipropilenos/análise , Polipropilenos/química , Poliestirenos/análise , Poliestirenos/química , Espectroscopia de Infravermelho com Transformada de Fourier , Urbanização , Poluentes Químicos da Água/química
8.
Mar Pollut Bull ; 145: 547-554, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31590822

RESUMO

Microplastics are becoming a global concern due to their potential to accumulate pollutants in aquatic environments. In this paper, sulfamethazine (SMT) sorption onto six types of microplastics, including polyamide (PA), polyethylene (PE), polyethylene terephthalate (PET), polypropylene (PP), polystyrene (PS), and polyvinyl chloride (PVC) was investigated by experimental and molecular dynamics simulation methods. The experimental results indicated that SMX sorption reached equilibrium within 16 h. The kinetics of SMT sorption by PA, PVC, PE, and PP could be fitted by pseudo first-order model, while SMT sorption by PA and PET could be described by pseudo second-order model. The partition coefficient Kd values were 38.7, 23.5, 21.0, 22.6, 18.6 and 15.1 L·kg-1 for PA, PE, PS, PET, PVC and PP, respectively. SMT sorption onto microplastics decreased when pH and salinity increased. The molecular dynamics simulation results indicated that the main mechanisms involved in sorption are electrostatic and Van der Waals interaction.


Assuntos
/química , Sulfametazina/química , Poluentes Químicos da Água/química , Adsorção , Concentração de Íons de Hidrogênio , Cinética , Simulação de Dinâmica Molecular , Polietileno/química , Polietilenotereftalatos , Polipropilenos/química , Poliestirenos/química , Cloreto de Polivinila/química , Eletricidade Estática
9.
Mar Pollut Bull ; 145: 604-610, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31590830

RESUMO

A floating plastic monitoring program was conducted for two years on a weekly basis in Banderas Bay, Mexico. A total of 94 samples were collected from May 2016 to April 2018 in the southern part of the bay. Half (57%) of them contained plastic debris; 79% of it being <5 mm in length. Polypropylene and Polyethylene were the most abundant polymers, accounting for 45% and 43% of the plastic pieces (pp), respectively. The highest abundance of plastic pieces was found in July 2016, with a maximum of 0.3 pp/m3 found in one sample. The amount of floating plastics was significantly higher in the hurricane season compared to the dry season (p < 0.001). This suggests that rainfall may play a significant role in the offload of plastics from land-based sources into the bay.


Assuntos
Plásticos/análise , Poluentes Químicos da Água/análise , Baías , Monitoramento Ambiental , México , Plásticos/química , Polietileno/análise , Polietileno/química , Polipropilenos/análise , Polipropilenos/química , Estações do Ano , Resíduos/análise
10.
Sensors (Basel) ; 19(20)2019 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-31614489

RESUMO

The use of metasurfaces operating in the terahertz regime as biosensor devices has attracted increased interest in recent years due to their enhanced sensitivity and more accurate detection capability. Typical designs are based on the replica of relatively simple unit cells, usually called metaatoms. In a previous paper, we proposed a new paradigm for ultrasensitive thin-film sensors based on complex unit cells, called generically metageometries or labyrinth metasurfaces. Here, we extend this concept towards biosensing, evaluating the performance of the labyrinth as a fungi detector. The sensing capabilities are numerically evaluated and a comparison with previous works in this field is performed, showing that metageometries improve the performance compared to metaatoms both in sensitivity and figure of merit, by a factor of more than four. In particular, we find that it is able to detect five fungi elements scattered on the unit cell, equivalent to a concentration of only 0.004/µm2.


Assuntos
Técnicas Biossensoriais/instrumentação , Análise Numérica Assistida por Computador , Eletricidade , Fungos/isolamento & purificação , Polipropilenos/química
11.
J Food Sci ; 84(11): 3194-3203, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31589346

RESUMO

A multilayer film containing star anise essential oil and thymol coating layers (SAEO and TH, respectively), with insect repellent and antimicrobial properties, has been developed using bar coating and adhesive lamination processes. Our previous study reported the in vitro activities of this polypropylene film (PP)/SAEO/polyethylene terephthalate film (PET)/TH/low-density polyethylene film (LDPE) multilayer film. The current study focused on demonstrating the morphological, optical, and mechanical properties of the film, and evaluating its in vivo activities when used as a bread packaging material. The developed film was 15.03% thicker and 1.86% less transparent than the control film (without active agent coating layers: PP/PET/LDPE). While the color values of the developed film were slightly different from the control film, both films appeared similar to the naked eye. The tensile strength in the developed film was somewhat lower than that of the control film, while both films had statistically comparable values for elongation at break. During storage of sliced bread packaged in the developed film, the film both deterred insects from approaching toward and impeded the growth of microorganisms in the bread. These results suggest the potential applicability of the developed film as an active food packaging material with insect repellent and antimicrobial activities. PRACTICAL APPLICATION: A multilayer film incorporated with insect repellent and antimicrobial coating layers was applied in sliced wheat bread packaging. The developed film effectively inhibited approaches of stored-product insects to packaged bread and growth of microorganisms on the bread surface. It can be used as an active food packaging material that improves the safety and shelf-life of foods.


Assuntos
Antibacterianos/química , Pão/análise , Conservação de Alimentos/métodos , Illicium/química , Repelentes de Insetos/química , Óleos Voláteis/química , Timol/química , Animais , Antibacterianos/farmacologia , Bactérias/efeitos dos fármacos , Bactérias/crescimento & desenvolvimento , Pão/microbiologia , Embalagem de Alimentos/instrumentação , Conservação de Alimentos/instrumentação , Repelentes de Insetos/farmacologia , Insetos/efeitos dos fármacos , Insetos/crescimento & desenvolvimento , Óleos Voláteis/farmacologia , Óleos Vegetais/química , Óleos Vegetais/farmacologia , Polietileno/química , Polipropilenos/química , Timol/farmacologia , Triticum/química , Triticum/microbiologia
12.
J Colloid Interface Sci ; 556: 529-540, 2019 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-31473542

RESUMO

The fast and scalable spray-drying-assisted evaporation-induced self-assembly (EISA) synthesis of hierarchically porous SBA-15-type silica microparticles from a water-based system is demonstrated. The SBA-15-type silica microparticles has bowl-like shapes, uniform micro-sizes (∼90 µm), large ordered mesopores (∼9.5 nm), hierarchical meso-/macropores (20-100 nm) and open surfaces. In the synthesis, soft- and hard-templating approaches are combined in a single rapid drying process with a non-ionic tri-block copolymer (F127) and a water-insoluble polymer colloid (Eudragit RS, 120 nm) as the co-templates. The RS polymer colloid plays three important roles. First, the RS nanoparticles can be partially dissolved by in-situ generated ethanol to form RS polymer chains. The RS chains swell and modulate the hydrophilic-hydrophobic balance of F127 micelles to allow the formation of an ordered mesostructure with large mesopore sizes. Without RS, only worm-like mesostructure with much smaller mesopore sizes can be formed. Second, part of the RS nanoparticles plays a role in templating the hierarchical pores distributed throughout the microparticles. Third, part of the RS polymer forms surface "skins" and "bumps", which can be removed by calcination to enable a more open surface structure to overcome the low pore accessibility issue of spray-dried porous microparticles. The obtained materials have high surface areas (315-510 m2 g-1) and large pore volumes (0.64-1.0 cm3 g-1), which are dependent on RS concentration, HCl concentration, silica precursor hydrolysis time and drying temperature. The representative materials are promising for the adsorption of lysozyme. The adsorption occurs at a >three-fold faster rate, in a five-fold larger capacity (an increase from 20 to 100 mg g-1) and without pore blockage compared with the adsorption of lysozyme onto spray-dried microparticles of similar physicochemical properties obtained without the use of RS.


Assuntos
Resinas Acrílicas/química , Micelas , Nanopartículas/química , Polietilenos/química , Polipropilenos/química , Dióxido de Silício/química , Adsorção , Animais , Proteínas Aviárias/química , Galinhas , Dessecação , Interações Hidrofóbicas e Hidrofílicas , Muramidase/química , Porosidade
13.
Int J Pharm Compd ; 23(5): 414-417, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31513540

RESUMO

Furosemide parenteral solutions are routinely used in our hospital. However, the stability in transparent syringes is unknown. In this study, transparent polypropylene syringes were filled with 8 mL and 50 mL of furosemide 5-mg/mL solution. The furosemide was analyzed by high-performance liquid chromatography and assays were performed up to 35 days of storage of the syringes at 4°C protected from light, plus 24 hours at 20°C exposed to daylight. In addition, the appearance and pH of the solutions were determined. A microbiological assay using tryptic soy broth was also performed. Both types of syringes remained colorless, clear, and free from visible particles throughout the study period. The pH did not change, and concentrations remained between 95% and 105% of the stated concentration. None of the syringes filled with culture media exhibited bacterial or fungal growth. In conclusion, ready-to-administer furosemide 5-mg/mL, 8-mL, and 50-mL polypropylene syringes are stable for up to 35 days when stored in a refrigerator at 4°C protected from light, plus 24 hours at 20°C unprotected from light. These results allow maximum storage time in stock and the ability of 24-hour continuous infusion at ambient room temperature without protecting the syringe against light.


Assuntos
Furosemida/química , Polipropilenos , Seringas , Cromatografia Líquida de Alta Pressão , Estabilidade de Medicamentos , Armazenamento de Medicamentos , Polipropilenos/química
14.
Int J Pharm Compd ; 23(5): 434-437, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31513544

RESUMO

In order to avoid fluid overload, the use of more concentrated drug solutions in intensive care units and obstetrics is common. The objective of this study was to quantify the physicochemical stability of a concentrated solution of salbutamol (albuterol) in polypropylene syringes during 30 days of storage at 5°C ± 3°C with protection from light. Four 50-mL syringes containing 0.060mg/mL of salbutamol (albuterol) in 0.9% NaCl were prepared and stored at 5°C ± 3°C with protection from light during 30 days of storage. Immediately after preparation and periodically during the storage, salbutamol (albuterol) concentrations were measured by an ultra-performance liquid chromatography. Spectrophotometric absorbance at different wavelengths, pH measurement, and microscopic observations were also performed. All solutions were physicochemically stable during the entire period of storage at 5°C ± 3°C: no color change, turbidity, precipitation or opacity, significant pH variations, or optic densities were observed in the solutions. No crystals were seen by microscopic analysis. Concentrations of salbutamol remained stable during the storage period. Solutions of salbutamol (albuterol) 0.060 mg/mL in syringes of 0.9% NaCl are physically and chemically stable for at least 30 days when stored in syringes at 5°C ± 3°C with protection from light and may be prepared in advance by a centralized intravenous additive service.


Assuntos
Obstetrícia , Polipropilenos/química , Seringas , Albuterol , Cromatografia Líquida de Alta Pressão , Unidades de Terapia Intensiva
15.
Proc Inst Mech Eng H ; 233(11): 1165-1174, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31545134

RESUMO

This study aimed to produce a composite of poly(propylene fumarate)/magnesium calcium phosphate as a substitutional implant in the treatment of trabecular bone defects. So, the effect of magnesium calcium phosphate particle size, magnesium calcium phosphate:poly(propylene fumarate) weight ratio on compressive strength, Young's modulus, and toughness was assessed by considering effective fracture mechanisms. Micro-sized (∼30 µm) and nano-sized (∼50 nm) magnesium calcium phosphate particles were synthesized via emulsion precipitation and planetary milling methods, respectively, and added to poly(propylene fumarate) up to 20 wt.%. Compressive strength, Young's modulus, and toughness of the composites were measured by compressive test, and effective fracture mechanisms were evaluated by imaging fracture surface. In both micro- and nano-composites, the highest compressive strength was obtained by adding 10 wt.% magnesium calcium phosphate particles, and the enhancement in nano-composite was superior to micro-one. The micrographs of fracture surface revealed different mechanisms such as crack pinning, void plastic growth, and particle cleavage. According to the results, the produced composite can be considered as a candidate for substituting hard tissue.


Assuntos
Materiais Biocompatíveis/química , Materiais Biocompatíveis/farmacologia , Osso e Ossos/efeitos dos fármacos , Fumaratos/química , Fenômenos Mecânicos , Fosfatos/química , Polipropilenos/química , Osso e Ossos/citologia , Força Compressiva , Injeções , Teste de Materiais , Relação Estrutura-Atividade
16.
Molecules ; 24(18)2019 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-31540285

RESUMO

Studies on the functionalization of materials used for the construction of filtering facepiece respirators (FFRs) relate to endowing fibers with biocidal properties. There is also a real need for reducing moisture content accumulating in such materials during FFR use, as it would lead to decreased microorganism survival. Thus, in our study, we propose the use of superabsorbent polymers (SAPs), together with a biocidal agent (biohalloysite), as additives in the manufacturing of polypropylene/polyester (PP/PET) multifunctional filtering material (MFM). The aim of this study was to evaluate the MFM for stability of the modifier's attachment to the polymer matrix, the degree of survival of microorganisms on the nonwoven, and its microorganism filtration efficiency. Scanning electron microscopy (SEM) and Fourier transform infrared (FTIR) spectroscopy were used to test the stability of the modifier's attachment. The filtration efficiency was determined under conditions of dynamic aerosol flow of S. aureus bacteria. The survival rates (N%) of the following microorganisms were assessed: Escherichia coli and Staphylococcus aureus bacteria, Candida albicans yeast, and Aspergillus niger mold using the AATCC 100-2004 method. FTIR spectrum analysis confirmed the pre-established composition of MFM. The loss of the active substance from MFM in simulated conditions of use did not exceed 0.02%, which validated the stability of the modifier's attachment to the PP/PET fiber structure. SEM image analysis verified the uniformity of the MFM structure. Lower microorganism survival rates were detected for S. aureus, C. albicans, and E. coli on the MFM nonwoven compared to control samples that did not contain the modifiers. However, the MFM did not inhibit A. niger growth. The MFM also showed high filtration efficiency (99.86%) against S. aureus bacteria.


Assuntos
Desinfetantes/farmacologia , Viabilidade Microbiana/efeitos dos fármacos , Polipropilenos/síntese química , Aspergillus niger/efeitos dos fármacos , Aspergillus niger/crescimento & desenvolvimento , Candida albicans/efeitos dos fármacos , Candida albicans/crescimento & desenvolvimento , Desinfetantes/química , Escherichia coli/efeitos dos fármacos , Escherichia coli/crescimento & desenvolvimento , Filtração/instrumentação , Microscopia Eletrônica de Varredura , Polímeros , Polipropilenos/química , Dispositivos de Proteção Respiratória/microbiologia , Espectroscopia de Infravermelho com Transformada de Fourier , Staphylococcus aureus/efeitos dos fármacos , Staphylococcus aureus/crescimento & desenvolvimento
17.
ACS Appl Mater Interfaces ; 11(35): 31671-31680, 2019 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-31397149

RESUMO

Hypoxia and overexpression of glutathione (GSH) are typical characteristics of the tumor microenvironment, which severely hinders cancer treatments. Here, we design a novel biodegradable therapeutic system, O2-Cu/ZIF-8@Ce6/ZIF-8@F127 (OCZCF), to simultaneously achieve GSH depletion and O2-enhanced combination therapy. Notably, the doped Cu2+ doubles the O2 storage capacity of the ZIF-8 matrix, which makes OCZCF an excellent pH-sensitive O2 reservoir for conquering tumor hypoxia, enhancing the photodynamic therapy (PDT) efficiency of chlorin e6 (Ce6) under 650 nm laser irradiation. Moreover, the released Cu2+ can act as a smart reactive oxygen species protector by consuming intracellular GSH. The byproduct Cu+ will undergo highly efficient Fenton-like reaction to achieve chemodynamic therapy (CDT) in the presence of abundant H2O2. The accompanying O2 will further alleviate hypoxia. The in vitro and in vivo experimental data indicate that OCZCF could cause remarkable tumor inhibition through enhanced synergetic PDT and CDT, which may open up a new path for cancer therapy.


Assuntos
Nanocompostos , Neoplasias Experimentais , Fotoquimioterapia , Polietilenos , Polipropilenos , Porfirinas , Microambiente Tumoral/efeitos dos fármacos , Animais , Linhagem Celular Tumoral , Preparações de Ação Retardada/química , Preparações de Ação Retardada/farmacocinética , Preparações de Ação Retardada/farmacologia , Feminino , Camundongos , Camundongos Endogâmicos BALB C , Nanocompostos/química , Nanocompostos/uso terapêutico , Neoplasias Experimentais/tratamento farmacológico , Neoplasias Experimentais/metabolismo , Neoplasias Experimentais/patologia , Polietilenos/química , Polietilenos/farmacocinética , Polietilenos/farmacologia , Polipropilenos/química , Polipropilenos/farmacocinética , Polipropilenos/farmacologia , Porfirinas/química , Porfirinas/farmacocinética , Porfirinas/farmacologia
18.
J Chromatogr A ; 1607: 460442, 2019 Dec 06.
Artigo em Inglês | MEDLINE | ID: mdl-31427137

RESUMO

This paper describes a new method for the effective extraction of the residues of five synthetic phenolic antioxidants (AOs): Ditertbutylphenol (DTF), Irganox 1010, Irganox 1076, Ethanox 330 and Cyanox 1790, from industrial water produced during the polypropylene (PP) deodorization process. In the deordorization process, PP is stored in a column for an average time of four hours and exposed to nitrogen and water vapor to remove inflammable compounds which may generate atypical odors in the PP. The samples of interest were taken in the desorber, followed by cleansing and pre-concentration using modified styrene divinylbenzene polymer cartridges. Liquid chromatography was performed with a reversed phase column and diode array. The method was validated for linearity, recovery, precision, specificity, limits of detection (LOD) and limits of quantification (LOQ). The chromatographic method showed LOQ from 5.4 to 16 mg L-1 and LOD between 1.6 and 4.8 mg L-1. The worldwide challenge to develop an analytical methodology which incorporates SPE with HPLC to identify and quantify AOs in industrial wastewater is addressed in this study. The recovery percentages were above 90% for most AOs, except for Irganox 1076 which showed a value of 83.2%. The ability to separate these five AOs of most frequent use worldwide, permits precision of measurement of the degree of contamination, making it useful for environmental regulation and the protection of public health.


Assuntos
Antioxidantes/análise , Cromatografia Líquida de Alta Pressão/métodos , Resíduos Industriais/análise , Fenóis/análise , Polipropilenos/química , Extração em Fase Sólida/métodos , Águas Residuárias/química , Calibragem , Limite de Detecção , Reprodutibilidade dos Testes , Poluentes Químicos da Água/análise
19.
J Food Sci ; 84(9): 2520-2527, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31408214

RESUMO

Previous study reported the development of insect-proof halloysite nanotubes (HNTs) and food packaging; however, the duration of their insecticidal properties remains unclear. Here, we aimed to (1) demonstrate the duration of repellency of clove bud oil (CO) encapsulated by HNTs for more than 30 days, and (2) manufacture insect-proof film containing HNTs for commercial use. Also, the release behavior of CO from insect-resistant HNTs was evaluated and HNTs were applied to food packaging composed of polypropylene and low-density polyethylene films to prevent Plodia interpunctella (Hübner) (Lepidoptera: Pyralidae) larva infestation. CO, a natural insecticide, was embedded with HNTs and polyethyleneimine (PEI) via vacuum pulling process to cause a slow and gradual release of CO. The sustained release profile of CO from CO-containing HNTs with a PEI coating [(HNTs/CO/layer-by-layer (LBL)] was verified by gas chromatography analysis. The repellent activity of HNTs/CO/LBL was observed for up to 46 days, whereas CO film and HNTs/CO film exhibited no insecticidal activities during the test period. After 30-day exposure, the HNTs/CO/LBL film exhibited a 7-day extension in the penetration test. To evaluate the insecticidal properties of the insect-proof film (HNTs/CO/LBL scale-up film) manufactured in an industrial facility, the inhibitory effects of HNTs/CO/LBL scale-up film on insect infestation was elucidated in both the segregation and combination tests. As a result, HNTs/CO/LBL alone or gravure-printed film treated with HNTs/CO/LBL were capable of protecting food from insect infestation. PRACTICAL APPLICATION: Halloysite nanotubes containing natural insect repellent were applied to industrial production of food packaging. Commercial cornflake cereal packaging using insect-resistant film successfully inhibited pest infestation. Insect-proof film produced at an industrial facility can be utilized to protect processed food from insect infestation.


Assuntos
Óleo de Cravo/farmacologia , Embalagem de Alimentos/instrumentação , Repelentes de Insetos/farmacologia , Inseticidas/farmacologia , Lepidópteros/efeitos dos fármacos , Nanotubos/química , Animais , Argila/química , Óleo de Cravo/química , Repelentes de Insetos/química , Inseticidas/química , Larva/efeitos dos fármacos , Larva/crescimento & desenvolvimento , Lepidópteros/crescimento & desenvolvimento , Polietileno/química , Polipropilenos/química
20.
J Pharm Pharmacol ; 71(11): 1655-1662, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31456253

RESUMO

INTRODUCTION: Hepatocellular carcinoma is the most common liver malignancy and the third leading cause of cancer death worldwide. One crucial limitation in the pharmacotherapy for this tumour is its chemotherapy-resistant nature produced by the overexpression of several members of the ATP-binding cassette protein family that efflux drugs out of cells, as observed with the breast cancer resistant protein (BCRP). OBJECTIVES: This study aimed to assess the ability of Pluronic® F127 to reverse the multidrug resistance phenotype in two human hepatocellular cell lines. METHODS: PLC/PRF/5 and SKHep1 cells were exposed to Pluronic® F127 at several concentrations. The effect of F127 on BCRP expression (mRNA and protein), mitochondrial transmembrane potential and cell hypodiploidy was assessed. Finally, the effect of this copolymer on cytotoxicity of doxorubicin in both hepatoma cell lines was investigated, as expressed by its reverse resistance index. KEY FINDINGS: It was demonstrated that F127 in both cell lines contributes to chemosensitization, as shown by BCRP down-regulation, an altered mitochondrial transmembrane potential and hypodiploidy and reverse resistance index values. A remarkable dependence of these effects significantly correlated with the copolymer concentration. CONCLUSIONS: These findings further uncover the potential usefulness of this copolymer as multidrug resistance reversal agent, increasing the efficacy of cancer therapies.


Assuntos
Doxorrubicina/sangue , Doxorrubicina/farmacologia , Poloxâmero/química , Polietilenos/química , Polipropilenos/química , Membro 2 da Subfamília G de Transportadores de Cassetes de Ligação de ATP/metabolismo , Carcinoma Hepatocelular/tratamento farmacológico , Linhagem Celular Tumoral , Regulação para Baixo/efeitos dos fármacos , Resistência a Múltiplos Medicamentos/efeitos dos fármacos , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Neoplasias Hepáticas/tratamento farmacológico , Potencial da Membrana Mitocondrial/efeitos dos fármacos
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