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1.
Food Chem ; 304: 125418, 2020 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-31479994

RESUMO

Low and high protein dairy powders are prone to caking and sticking and can also be highly insoluble; with powder storage conditions an important factor responsible for such issues. The aim of this study focused on the bulk and surface properties of anhydrous and humidified spray-dried milk protein concentrate (MPC) powders (protein content ~40, 50, 60, 70 or 80%, w/w). Water sorption isotherms, polarized light and scanning electron micrographs showed crystallized lactose in low protein powders at high water activities. High protein systems demonstrated increased bulk diffusion coefficients compared to low protein systems. Glass transition temperatures, α-relaxation temperatures and structural strength significantly decreased with water uptake. CLSM measurements showed that humidified systems have slower real time water diffusion compared to anhydrous systems. Overall, the rate of water diffusion was higher for low protein powders but high protein powders absorbed higher levels of water under high humidity conditions.


Assuntos
Lactose/química , Proteínas do Leite/química , Pós/química , Água/química , Laticínios/análise , Difusão , Umidade , Propriedades de Superfície , Temperatura Ambiente
2.
Food Chem ; 302: 125338, 2020 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-31434027

RESUMO

This study was designed to evaluate the baking performances of 25 edible dry bean (Phaseolus vulgaris L.) varieties and to investigate correlations among cookie features and rapid test indices (i.e., water and lactic acid retention capacities, oil binding capacity and Rapid Visco Analyzer indices). Two bean powder particle sizes (≤0.5 mm, ≤1.0 mm) were investigated. Cookies were evaluated in terms of nutritional, geometrical and textural properties. Bean powders doubled the amount of cookie protein and increased cookie resistant starch content. Baking potential varied according to bean genotype and powder particle size: coarse powders resulted in larger (+26%) and thinner (-19%) cookies characterized by easier breaking texture (fracture strengths of 41-157 vs. 48-226 kPa for fine powders). Water retention and oil binding capacities and pasting properties significantly (p < 0.05) correlated with cookie features. In conclusion, these accumulated findings can be used in designing value-added traditional and gluten-free cookies.


Assuntos
Phaseolus/química , Pós/química , Culinária , Dieta Livre de Glúten , Farinha , Ácido Láctico/análise , Ácido Láctico/química , Valor Nutritivo , Tamanho da Partícula , Amido/análise , Água/análise , Água/química
3.
Water Res ; 167: 115137, 2019 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-31585386

RESUMO

Two submerged anaerobic membrane bioreactors (AnMBRs) with and without powdered activated carbon (PAC) were studied to revisit the effect of PAC on membrane fouling performance by long-term operation when treating synthetic sewage. The results showed that PAC remained efficient for membrane fouling control after long-term operation (over 140 d), and it reduced the fouling rate at a hydraulic retention time of 8 h from 3.12 to 0.89 kPa/d. PAC mainly mitigated the membrane fouling by restraining the formation of a cake layer while generating a gel layer on the membrane surface, which was attributed to the PAC-induced microbial community change in mixed liquor and the membrane surface. Microbial community analysis indicated the genera Pseudomonas (26.5%) and Methanothrix (79.21%) were the predominant bacteria and archaea, respectively, in the gel layer, and this result is completely different from the presence of a high abundance of Levilinea (7.1%), Aminivibrio (4.9%) and Methanothrix (90.04%) in the cake layer on the membrane surface without PAC. The significant difference in the predominant microbes in the membrane surface layer was attributed to the reduced enrichment of Levilinea and Methanothrix with PAC addition.


Assuntos
Carvão Vegetal , Membranas Artificiais , Anaerobiose , Reatores Biológicos , Pós , Esgotos
4.
Pharm Res ; 36(12): 167, 2019 Oct 24.
Artigo em Inglês | MEDLINE | ID: mdl-31650274

RESUMO

PURPOSE: Oral direct compressible tablets are the most frequently used drug products. Manufacturing of tablets requires design and development of formulations, which need a number of excipients. The choice of excipients depends on the concentration, manufacturability, stability, and bioavailability of the active pharmaceutical ingredients (APIs). At MIT, we developed a miniature platform for on-demand manufacturing of direct compressible tablets. This study investigated how formulations could be simplified to use a small number of excipients for a number of different API's in which long term stability is not required. METHOD: Direct compressible tablets of five pharmaceutical drugs, Diazepam, Diphenhydramine HCl, Doxycycline Monohydrate, Ibuprofen, and Ciprofloxacin HCl, with different drug loadings, were made using direct compression in an automated small scale system.. The critical quality attributes (CQA) of the tablets were assessed for the quality standards set by the United States Pharmacopeia (USP). RESULTS: This miniature system can manufacture tablets - on-demand from crystalline API using the minimum number of excipients required for drug product performance. All drug tablets met USP quality standards after manufacturing and after 2 weeks of accelerated stability test, except for slightly lower drug release for Ibuprofen. CONCLUSIONS: On-demand tablets manufacturing where there is no need for long term stability using a flexible, miniature, automated (integrated) system will simplify pharmaceutical formulation design compared to traditional formulations. This advancement will offer substantial economic benefits by decreasing product time-to-market and enhancing quality.


Assuntos
Excipientes/química , Comprimidos/química , Ciprofloxacino/química , Diazepam/química , Difenidramina/química , Doxiciclina/química , Composição de Medicamentos/métodos , Liberação Controlada de Fármacos , Ibuprofeno/química , Tamanho da Partícula , Pós/administração & dosagem , Pós/química , Solubilidade , Solventes/química , Comprimidos/administração & dosagem
5.
Pharm Res ; 36(12): 173, 2019 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-31659476

RESUMO

PURPOSE: In the present study the influence and application of a newly developed external lower punch vibration system for an improved die filling on a running rotary tablet press was investigated. METHODS: Tablets were manufactured at different conditions (with and without vibration) and characterized regarding their direct compressibility and mechanical stability. Thus, two typical pharmaceutical binders for direct compression (Parmcel 102 and Tablettose® 80) were compared with two binders unsuitable for direct compression (Ceolus® KG1000 and GranuLac® 200). The powders were characterized by helium pycnometry, laser diffraction, scanning electron microscopy, and by determination of the powder flow. Furthermore, a novel technique to determine the occurrences of segregation within a tablet after manufacturing was introduced. For this purpose, a powder blend containing one spray-colored type of microcrystalline cellulose (Vivapur® 200) were prepared. RESULTS: It was shown that under application of externally applied lower punch vibration, the powder flow into the die increased and thus the die filling process was significantly improved. Hence, it was possible to manufacture tablets from powders, which are actually unsuitable for direct compression. In addition, the mechanical stability of the produced tablets was distinctly improved by application of lower punch vibration, whereby the occurrence of segregation was comparatively low. CONCLUSION: In summary, lower punch vibration allows a more efficient die filling, whereby the powder flow as well as mechanical stability of the tablets are improved.


Assuntos
Celulose/química , Excipientes/química , Comprimidos/química , Composição de Medicamentos/métodos , Estabilidade de Medicamentos , Fenômenos Mecânicos , Pós/química , Vibração
6.
Eur J Pharm Biopharm ; 145: 7-11, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31605741

RESUMO

The usefulness, the high production rate and the cost effectiveness make tablets the dosage form of choice for oral probiotics. Nevertheless, probiotic bacteria undergo a lot of mechanical stress during tableting which causes damage to their cell wall and membrane and other bio-active components. This can lead to an inactivation of the probiotic bacteria and therefore in a failure of the probiotic therapy. To obtain a tablet with a sufficient amount of viable cells, research on the influence of formulation and process parameters on bacterial survival is essential. This study aimed to decipher tableting properties of the probiotic powder blends that have a major impact on survival rates. The powder blends consisted of the prototype probiotic strain Lactobacillus rhamnosus GG, a filler-binder and a suitable amount of lubricant. They were manufactured by direct compression at different compression pressures and tableting speeds. The tableting properties were analysed in detail by a 3-D modelling technique, which characterized normalized time, pressure and displacement simultaneously. The results of the 3-D modelling demonstrated the significant effect of the pressure plasticity (e) and the angle of rotation (ω) on the viability of L. rhamnosus GG during direct compression.


Assuntos
Força Compressiva/efeitos dos fármacos , Probióticos/química , Comprimidos/química , Química Farmacêutica/métodos , Excipientes/química , Lactobacillus rhamnosus/química , Pós/química , Pressão
7.
Zhongguo Zhong Yao Za Zhi ; 44(15): 3195-3202, 2019 Aug.
Artigo em Chinês | MEDLINE | ID: mdl-31602872

RESUMO

Dry granulation technology is a great innovation in granulation technology,which saves many intermediate links and reduces many intermediate costs. It is closely related to the characteristics of materials,dry granulation equipment and process. Dry granulation technology is a systematic engineering science covering many technical fields. The process of dry granulation involves complex mathematical model mechanisms of temperature field,pressure field and velocity field,closely related to the characteristics of materials and drying equipment. However,due to the late start of research on dry granulation technology of traditional Chinese medicine,basic research is still weak. The research on dry granulation technology has achieved great results in the fields of food,chemical industry,agriculture and forestry,showing great reference significance. The advantage of dry granulation of traditional Chinese medicine is that it can be directly granulated by adding an appropriate amount of auxiliary materials in the extract powder of traditional Chinese medicine,without the need of wetting,mixing,drying and other processes. The process is simple and can effectively guarantee the quality of traditional Chinese medicine. The granules obtained by the dry granulation technique are important intermediates for preparing the solid preparations of traditional Chinese medicines,which would directly affect the subsequent molding process and the quality of the preparation products. Therefore,based on the characteristics of dry granulation method in traditional Chinese medicine and by referring to the advanced research results of dry granulation technology in other fields,we would discuss the research ideas of dry granulation in traditional Chinese medicine in terms of the mechanism of dry granulation equipment,technology,on-line detection technology and mathematical model of dry granulation process,hoping to provide reference for the research of dry granulation method in traditional Chinese medicine.


Assuntos
Dessecação , Medicina Tradicional Chinesa , Tecnologia Farmacêutica , Medicamentos de Ervas Chinesas , Modelos Teóricos , Pós , Controle de Qualidade
8.
Hua Xi Kou Qiang Yi Xue Za Zhi ; 37(4): 438-442, 2019 Aug 01.
Artigo em Chinês | MEDLINE | ID: mdl-31512841

RESUMO

With the rapid development of 3D printing, it is widely used in the field of cranio-maxillofacial surgery. Through the individualized production of 3D printing, the backward mode of traditional production relying on manual shaping has been changed to meet the needs of different patients. However, as no clear specification exists for the performance requirements of 3D printing metal powder for cranio-maxillofacial surgery, its long-term development is not feasible. In this paper, the preparation technologies of 3D printing metal powder for cranio-maxillofacial prostheses (i.e., gas atomization, rotating electrode atomization, and radio frequency plasma spheroidization) and 3D printing forming technologies (i.e., selective laser melting, electron beam selective melting, and laser-engineered net shaping) are introduced. The performance requirements of 3D printing metal powder for cranio-maxillofacial prostheses are then summarized according to the characteristics of the preparation and forming technologies described.


Assuntos
Prótese Maxilofacial , Impressão Tridimensional , Humanos , Lasers , Metais , Pós
9.
Waste Manag ; 99: 60-70, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31472441

RESUMO

Life cycle assessment of recycling rare earths from waste fluorescent powders was conducted, including the uncertainty and sensitivity analyses. Three scenarios were set in this study, namely, recycling with/without final disposal and waste fluorescent powders landfill. Recycling with final disposal presented lower environmental burden than that without final disposal due to the significant reduction of direct emissions. The evident impacts from chemicals and energy production stages were considered the main contributors to the overall environmental burden of recycling with final disposal due to their relatively high emissions of particulates matter, sulfur dioxide, heavy metals, and carbon dioxide as well as the use of fossil fuel. Compared with landfills, rare-earth recycling shows the highest environmental benefits because of the substitution of primary rare earths. To relieve the high demand of rare earths and reduce the overall environmental burden, governments are highly recommended to increase recycle rate, create a complete management system, improve energy consumption and wastewater treatment efficiency, and build an adequate recycle standard.


Assuntos
Metais Terras Raras , Eliminação de Resíduos , Gerenciamento de Resíduos , China , Pós , Reciclagem , Instalações de Eliminação de Resíduos
10.
Bioresour Technol ; 294: 122137, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31536858

RESUMO

Concerning the lack of comprehensive study on the impact of powdered and granular activated carbon (PAC and GAC) on AnMBR, their impact on treatment performance, mixed liquor and cake layer properties and membrane fouling behaviors were further investigated. High COD removal efficiencies (>90%) and COD converting to CH4 rates (>70%) were achieved. GAC greatly increased extracellular polymeric substances (EPS) production in mixed liquor, but significantly reduced biosolids deposited on membrane surface; while PAC largely increased proteins and polysaccharides on membrane surface. In addition, PAC decreased, whereas GAC increased particle sizes. Fouling rates showed PAC and GAC addition effectively alleviated membrane fouling at HRT 8 h, and GAC remarkably postponed the occurrence of the transmembrane pressure jump and extended membrane service time. This study clarified the roles of GAC and PAC on membrane fouling control over long-term operation, which provides the basis for decision-making in practical application.


Assuntos
Carvão Vegetal , Membranas Artificiais , Anaerobiose , Reatores Biológicos , Pós , Esgotos
11.
Eur J Pharm Biopharm ; 144: 68-78, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31493511

RESUMO

Medicated chewing gums represent an orally administered dosage form with promising potential for local and systemic drug delivery. However, compared to other solid oral dosage forms, formulation development and release mechanism of medicated chewing gums are extremely complex, and thus only few products reached the approval for the market so far. Therefore, Quality by Design (QbD) approaches for rational formulation development of medicated chewing gums are needed to utilize their full potential. For chewing gum tablets, which are manufactured by direct compression, QbD approaches derived from tableting processes might be exerted. In this context, the SeDeM-Diagram-Expert-System implements the QbD approach while indicating whether a blend is suitable for direct compression and comprises powder properties, which need to be improved to facilitate the formulation development. Here, we present the successful application of the SeDeM-Diagram-Expert-System to the formulation development of medicated chewing gum tablets manufactured by direct compression. Furthermore, limitations of the SeDeM-System for medicated chewing gum tablets are evaluated and potential modifications of the system are suggested and discussed for future use.


Assuntos
Comprimidos/química , Química Farmacêutica/métodos , Goma de Mascar , Composição de Medicamentos/métodos , Sistemas de Liberação de Medicamentos/métodos , Excipientes/química , Sistemas Especialistas , Pós/química
12.
Eur J Pharm Biopharm ; 144: 139-153, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31536784

RESUMO

Trehalose is commonly used as a protein stabilizer in spray dried protein formulations delivered via the pulmonary route. Spray dried trehalose formulations are highly hygroscopic, which makes them prone to deliquescence and recrystallization when exposed to moisture, leading to impairment in aerosolization performance. The main aim of this study was to investigate and compare the effect of hydrophobic amino acids (i.e. L-leucine and L-isoleucine) in enhancing aerosolization performance and in mitigating moisture-induced changes in spray dried trehalose formulations. Trehalose was spray dried with 20-60% w/w of amino acid (i.e. L-leucine or L-isoleucine). The spray dried formulations were stored at 25 °C/50% RH for 28 days. Solid state characterization and in vitro aerosolization performance studies were performed on the spray dried formulations before and after storage. The addition of 20-60% w/w of amino acid (i.e. L-leucine or L-isoleucine) improved the emitted fractions of spray dried trehalose formulations from a dry powder inhaler. However, ≥ 40% w/w of L-leucine/L-isoleucine was needed to prevent recrystallization of trehalose in the formulations when exposed to 25 °C/50% RH for 28 days. X-ray photoelectron spectroscopy (XPS) demonstrated that samples with 40-60% w/w L-isoleucine had more amino acid on the surfaces of the particles compared to their L-leucine counterparts. This may explain the greater ability of the L-isoleucine (40-60% w/w) samples to cope with elevated humidity compared to L-leucine samples of the same concentrations, as observed in the dynamic vapour sorption (DVS) studies. In conclusion, this study demonstrated that both L-leucine and L-isoleucine were effective in enhancing aerosolization performance and mitigating moisture-induced reduction in aerosolization performance in spray dried trehalose formulations. L-isoleucine proved to be superior to L-leucine in terms of its moisture protectant effect when incorporated at the same concentration in the formulations.


Assuntos
Aminoácidos/química , Trealose/química , Administração por Inalação , Aerossóis/química , Química Farmacêutica/métodos , Composição de Medicamentos/métodos , Inaladores de Pó Seco/métodos , Umidade , Interações Hidrofóbicas e Hidrofílicas , Leucina/química , Pós/química , Molhabilidade/efeitos dos fármacos
13.
J Food Sci ; 84(9): 2482-2489, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31476025

RESUMO

Powderization of oils has been used as a method to enhance the stability of polyunsaturated fatty acids. Previously, we successfully powderized soybean oil via nozzleless electrostatic atomization. The process of nozzleless electrostatic atomization process was applied to the one-step process of encapsulating oil in wall materials. The encapsulation of oils in powder is dependent on the wall materials. The present study aimed to resolve the behavior of oil encapsulated in particles using a novel method of electrostatic atomization, and to investigate the effect of wall materials on the oil content in the encapsulated formulations. The size of particles surrounding oil was dependent on the type of wall materials used for encapsulation, and the oil content within the encapsulation decreased with increase in particle size. Furthermore, wall materials with higher hydrophobicity increased the oil content within the encapsulation, as more hydrophobic particles could absorb the oil more effectively. PRACTICAL APPLICATION: Nozzleless electrostatic atomization is a new method for preparing encapsulation of oil using various wall materials.


Assuntos
Materiais Biocompatíveis/química , Pós/química , Óleo de Soja/química , Composição de Medicamentos , Interações Hidrofóbicas e Hidrofílicas , Tamanho da Partícula , Eletricidade Estática
14.
Toxicol Lett ; 316: 119-126, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31539570

RESUMO

In vivo experiments are still widely used for the testing of lung toxicity but there is an ethical and legal obligation to replace, reduce and refine animal testing. Lung A549 cells could serve as an in vitro indicator for acute lung toxicity but little data about the correlation of the cytotoxicity in A549 cells and data leading to CLP classifications are available. We exposed A549 cells to 19 CLP-classified substances with doses of 25, 50, and 100 µg/cm2 either under submerged (SME) condition or with aerosols at the air-liquid interface (ALIF) and determined accuracy, precision, sensitivity and the F1 score with the CLP classifications H330, H332, or H335. When data from both exposure methods were combined, we found accuracies of 0.84 ±â€¯0.05, precisions of 0.74 ±â€¯0.1, sensitivities of 0.93 ±â€¯0.08 and F1 scores of 0.82 ±â€¯0.04. Separated from each other, ALIF exposure was more sensitive at any dose but, at higher doses, also less accurate and precise compared to SME. Considering the 19 substances tested, our data suggest that cytotoxicity in A549 cells could be a reliable in vitro indicator for in vivo toxicity. Thus, we discuss how A549 could be integrated into validation test guidelines.


Assuntos
Lesão Pulmonar Aguda/induzido quimicamente , Alternativas aos Testes com Animais/métodos , Células Epiteliais/efeitos dos fármacos , Células Epiteliais/patologia , Neoplasias Pulmonares/patologia , Material Particulado/toxicidade , Células A549 , Animais , Sobrevivência Celular/efeitos dos fármacos , Relação Dose-Resposta a Droga , Fibroblastos/efeitos dos fármacos , Fibroblastos/patologia , Humanos , Camundongos , Tamanho da Partícula , Pós , Reprodutibilidade dos Testes , Medição de Risco
15.
Eur J Pharm Biopharm ; 142: 543-552, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31398437

RESUMO

Recently we showed that nebulized ciprofloxacin and phage PEV20 in combination had a synergistic bactericidal effect against antibiotic-resistant Pseudomonas aeruginosa isolates from patients with cystic fibrosis. Compared to nebulization, dry powders for inhalation may improve patient handling characteristics and compliance. In the present study, we co-spray dried ciprofloxacin and phage PEV20 using L-leucine with or without lactose as excipients. Two formulations were identified for testing in this study. The mass ratios were set at 1:1:1 for ciprofloxacin, lactose and L-leucine (Formulation A) or 2:1 for ciprofloxacin and L-leucine without lactose (Formulation B). Concentrations of PEV20 were set at 108 and 109 PFU/mL for two clinical P. aeruginosa strains FADD1-PA001 and JIP865, respectively. Formulations A and B were characterized as partially crystalline and the powders recrystallized at >40% relative humidity (RH). Both formulations exhibited strong synergistic antimicrobial killing effect on the two strains. Formulations A and B maintained bactericidal synergy after dispersion using both low and high resistance Osmohaler™. Powder aerosol performance was examined by next generation impactor (NGI) in low resistance inhaler at 100 L/min and by multi-stage liquid impinger (MSLI) in high resistance inhaler at 60 L/min. Fine particle fractions (FPF) obtained by NGI were 59.7 ±â€¯2.1% and 64.3 ±â€¯2.9% for A and B, respectively. FPF obtained by MSLI were 71.0 ±â€¯3.4% and 73.3 ±â€¯5.0%, respectively. In conclusion, it is feasible to prepare stable and inhalable combination powder formulations of phage PEV20 and ciprofloxacin for potential treatment of respiratory infections caused by multi-drug resistant (MDR) P. aeruginosa.


Assuntos
Bacteriófagos/classificação , Ciprofloxacino/administração & dosagem , Ciprofloxacino/química , Pós/química , Infecções Respiratórias/tratamento farmacológico , Administração por Inalação , Aerossóis/química , Antibacterianos/administração & dosagem , Antibacterianos/química , Química Farmacêutica/métodos , Fibrose Cística/microbiologia , Inaladores de Pó Seco/métodos , Excipientes/química , Humanos , Lactose/química , Nebulizadores e Vaporizadores , Tamanho da Partícula , Infecções por Pseudomonas/tratamento farmacológico , Pseudomonas aeruginosa/efeitos dos fármacos
16.
J Agric Food Chem ; 67(36): 10265-10272, 2019 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-31423777

RESUMO

Infant formula (IF), regarded as the optimal substitute for human breast milk, is very important for infant growth and development. Phospholipids (PLs) are ubiquitous components of infant formula as they have good emulsifier properties in addition to their nutritional and biological functions. In this study, the PL contents in four different commercial IF brands (indicated as A, M, O, and W) were characterized and quantified using optimized 31P NMR spectroscopy. PLs (nine) were identified and quantified, and among these, phosphatidylethanolamine and sphingomyelin occurred at lower concentrations (5.72 and 8.89 mg/100 g, respectively) in IFs from brand O, whereas phosphatidic acid was higher (2.83 mg/100 g) in IFs from brand W. In summary, 31P NMR spectroscopy, combined with the multivariate data analysis, proved to be an effective analytical toolbox for evaluating the PL contents in IF and the comparative differences between IF brands.


Assuntos
Fórmulas Infantis/química , Espectroscopia de Ressonância Magnética/métodos , Fosfolipídeos/química , Pós/química
17.
J Environ Manage ; 248: 109314, 2019 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-31376611

RESUMO

Magnetic powdered activated carbon (Mag-PAC) was successfully developed and applied as an adsorbent for dissolved organic matter (DOM) removal from the effluent of a membrane bioreactor (MBR) using batch experiments. The results show that a coating of iron oxide particles is consistently distributed on the surface of powdered activated carbon (PAC), resulting in a decrease in the specific surface area and in the pH at the point of zero charge, even though the particle sizes of Mag-PAC and PAC were similar. A Mag-PAC dosage of 4 g/L exhibited efficient and fast DOM adsorption with a relatively short contact time of 5 min. The iron oxide coating on the surface of PAC may play an important role in the DOM removal efficiency. Temkin isotherm and pseudo-second order kinetic models well described the DOM adsorption, suggesting that the adsorption of DOM onto Mag-PAC could be mainly governed by a chemisorption mechanism. Humic acid- and fulvic acid-like compounds and aromatic DOM with molecular weights (MWs) between 2610 Da and 3030 Da were efficiently removed by Mag-PAC, whereas aromatic DOM with an MW of 1760 Da was poorly removed. Our results demonstrate that the application of Mag-PAC for DOM adsorption is attractive and yields benefits as a posttreatment system for MBR effluent due to its efficient and fast DOM adsorption.


Assuntos
Poluentes Químicos da Água , Purificação da Água , Adsorção , Reatores Biológicos , Carvão Vegetal , Pós
18.
Eur J Pharm Biopharm ; 143: 61-69, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31445157

RESUMO

Localized aerosol delivery of gene therapies is a promising treatment of severe pulmonary diseases including lung cancer, cystic fibrosis, COPD and asthma. The administration of drugs by inhalation features multiple benefits including an enhanced patient acceptability and compliance. The application of a spray dried powder formulation has advantages over solutions due to their increased stability and shelf life. Furthermore, optimal sizes of the powder can be obtained by spray drying to allow a deep lung deposition. The present study optimized the parameters involved with spray drying polyplexes formed by polyethylenimine (PEI) and nucleic acids in inert excipients to generate a nano-embedded microparticle (NEM) powder with appropriate aerodynamic diameter. Furthermore, the effects of the excipient matrix used to generate the NEM powder on the biological activity of the nucleic acid and the ability to recover the embedded nanoparticles was investigated. The study showed that bioactivity and nucleic acid integrity was preserved after spray drying, and that polyplexes could be reconstituted from the dry powders made with trehalose but not mannitol as a stabilizer. Scanning electron microscopy (SEM) showed trehalose formulations that formed fused, lightly corrugated spherical particles in the range between 1 and 5 µm, while mannitol formulations had smooth surfaces and consisted of more defined particles. After redispersion of the microparticles in water, polyplex dispersions are obtained that are comparable to the initial formulations before spray drying. Cellular uptake and transfection studies conducted in lung adenocarcinoma cells show that redispersed trehalose particles performed similar to or better than polyplexes that were not spray dried. A method for quantifying polymer and nucleic acid loss following spray drying was developed in order to ensure that equal nucleic acid amounts were used in all in vitro experiments. The results confirm that spray dried NEM formulations containing nucleic acids can be prepared with characteristics known to be optimal for inhalation therapy.


Assuntos
Nanopartículas/química , Ácidos Nucleicos/química , Polietilenoimina/química , Pós/química , Células A549 , Administração por Inalação , Aerossóis/química , Varredura Diferencial de Calorimetria/métodos , Linhagem Celular Tumoral , Química Farmacêutica/métodos , Dessecação/métodos , Excipientes/química , Humanos , Manitol/química , Microscopia Eletrônica de Varredura/métodos , Tamanho da Partícula , Trealose/química
19.
J Food Sci ; 84(9): 2528-2536, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31433070

RESUMO

Wheat flour may be thermally processed to improve microbiological safety; however, come-up time for thermal processing of wheat flour is long due to its low thermal conductivity. In the present study, a novel radiofrequency (RF)-assisted thermal processing approach was investigated for reducing the come-up time of soft wheat flour (SWF) and for improving microbiological safety. The temperature and time combinations of 80 °C for 7 and 10 hr, 90 °C for 2 and 3 hr, and 100 °C for 0.75 and 1 hr for RF-assisted thermal processing were selected to achieve a minimum of a 7-log reduction in Salmonella spp. The quality and functional properties of RF-assisted thermally processed SWF was evaluated by solvent retention capacity (SRC), swelling power, sodium dodecyl sulfate sedimentation tests, and rapid-visco-analyzer test, and the values were compared with the untreated (unpasteurized) and commercially pasteurized SWF. All the SRC attributes at 80 °C for 7 hr, 90 °C for 2 hr and 100 °C for 0.75 hr were not significantly different from that of the unpasteurized SWF. The optimum RF-assisted thermal processing conditions of 80 °C for 7 hr and 90 °C for 2 hr were recommended for pasteurization of SWF without any compromise in the quality and functionality. PRACTICAL APPLICATION: Thermal processing of low-moisture foods such as flours and powders through traditional methods is not practical due to extremely long come-up times. Novel radiofrequency-assisted thermal processing is poised to reduce the processing time 89 times for 100 °C. The processing parameters determined in this study will enhance the microbiological safety of wheat flour without compromising the quality and functionality.


Assuntos
Farinha/análise , Manipulação de Alimentos/métodos , Triticum/química , Farinha/microbiologia , Manipulação de Alimentos/instrumentação , Temperatura Alta , Pasteurização , Pós/química , Ondas de Rádio , Salmonella/crescimento & desenvolvimento , Salmonella/efeitos da radiação , Condutividade Térmica , Triticum/microbiologia
20.
Forensic Sci Int ; 302: 109905, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31394460

RESUMO

Fingerprint detection and Short Tandem Repeat (STR) typing are two approaches used for identification of individuals. The main goal of forensic laboratories is the development of a standardized protocol to obtain an STR profile from latent fingerprints, by typing the DNA transferred onto touched objects. The results obtained in this field derive from studies conducted under controlled laboratory conditions. Here, for the first time, we report two different profiles obtained by DNA purified by latent fingerprints enhanced with dactyloscopic powders at a crime scene, 14 years previously. DNA extraction phase was optimized to improve removal of powder and automatically conducted. Despite the low concentration of purified DNA, it was not degraded. Even if quality of the profile is influenced by several factors such as the method of acquisition and storage conditions of the fingerprint, results obtained are adequately informative and could be uploaded to the CODIS database.


Assuntos
Impressões Digitais de DNA/métodos , DNA/isolamento & purificação , Dermatoglifia , Repetições de Microssatélites , Eletroforese Capilar , Humanos , Pós , Reação em Cadeia da Polimerase em Tempo Real , Análise de Regressão , Manejo de Espécimes/métodos
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