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1.
Nanotechnology ; 33(15)2022 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-34965518

RESUMO

Diurea modified h-BN nanosheet is a novel kind of 2D gelator that could gel the lubricating oils under the stimulus of ultrasound. Morphological analyzations in previous study confirmed that the ultrasound induced layer-by-layer (LBL) structure of BN gelator is critical for the gelation. However, the elastic response in LBL structure, which is crucial for the formation of a stable gel system, has not been explicitly illustrated yet. The challenge is that the LBL gelator structure is based on 2D material and thus lacks vertical linkage between gelator layers, which is significantly different from the traditional gel systems that generally possess highly crosslinked gelator network. In this work, by investigating the viscoelastic behavior of the BN-based gel via rheometer, it is found the solid-liquid interface interaction, which is regulated by the diurea molecular structure in the BN gelator, is the key factor for triggering the stable elastic response in the LBL structure, and the elasticity mainly originates from the interface interaction induced bending deformation of h-BN 2D material. The findings further elucidate the gelling mechanism of BN gelators and enlighten the structure design of ultrasound-responsive gelator based on 2D materials.

2.
J Food Sci Technol ; 51(8): 1517-24, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25114342

RESUMO

The selection of appropriate wheat cultivars is an imperative issue in product development and realization. The nutritional profiling of plants and their cultivars along with their suitability for development of specific products is of considerable interests for multi-national food chains. In this project, Pizza-Hut Pakistan provided funds for the selection of suitable newly developed Pakistani spring variety for pizza production. In this regard, the recent varieties were selected and evaluated for nutritional and functional properties for pizza production. Additionally, emphasis has been paid to assess all varieties for their physico-chemical attributes, rheological parameters and mineral content. Furthermore, pizza prepared from respective flour samples were further evaluated for sensory attributes Results showed that Anmool, Abadgar, Imdad, SKD-1, Shafaq and Moomal have higher values for protein, gluten content, pelshenke value and SDS sedimentation and these were relatively better in studied parameters as compared to other varieties although which were considered best for good quality pizza production. TD-1 got significantly highest score for flavor of pizza and lowest score was observed from wheat variety Kiran. Moreover, it is concluded from current study that all wheat varieties except TJ-83 and Kiran exhibited better results for flavor.

3.
Appl Radiat Isot ; 214: 111526, 2024 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-39326349

RESUMO

External beam radiotherapy is a treatment modality that employs high doses for curative or palliative purposes. Safety in such treatments, particularly with high-precision equipment, necessitates strict adherence to quality control protocols to ensure the efficacy of oncological treatments. In this context, chemical dosimeters, particularly the Fricke gel, have emerged as valuable tools for quantitatively analysing absorbed radiation doses. These dosimeters can be applied both as tissue-equivalent phantoms and as radiation detectors in radiotherapy centers. The objective of this study was to evaluate the feasibility of new gelling matrices, comprising common materials such as CMC, GGU, and PVA, for producing ferrous sulphate dosimeters aimed at the relative quantification of radiation dose. A rheological study was conducted for different Fricke gel dosimetric formulations. Initially, the performance of these dosimeters, produced at various gel concentrations, was evaluated in terms of their consistency at room temperature. This was achieved through the straightforward process of humidification the gels with glycerine. These matrices consist of both natural and synthetic polymers that are readily accessible, easy to handle, and can be easily incorporated into the acidic ferrous sulphate solution. Parameters such as the influence of gelling matrix concentration, linearity, and stability were assessed and correlated with those previously investigated for Fricke gel produced with bloom 300 pig skin gelatine (GEL). Ferrous sulphate dosimeters fabricated with sodium carboxymethylcellulose (CMC), guar gum (GGU), and polyvinyl alcohol (PVA) exhibited a coefficient of variation of less than 1% relative to the dose response evaluated in this study. By using readily available and easily manageable materials, it is possible to replicate dosimeters with a favourable dosimetric response for high-dose measurements.

4.
Eur J Pharm Biopharm ; 191: 103-113, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37582410

RESUMO

Solubility is a critical parameter in drug formulation to achieve the desired therapeutical concentration. Most drugs are weak acids or bases and, therefore, exhibit low solubility and poor oral availability. The main aim of this work is the use of Deep Eutectic Systems (DESs) for improving the solubility of drugs in aqueous medium. In this case, we use DESs formed by choline chloride and sugars (xylitol, fructose, glucose and sorbitol) at different proportions of water. These compounds present low toxicity, and thus can be used in syrups or liquid formulations. Different physicochemical properties, such as density, refractive index, and surface tension, were obtained. In addition, a rheological study of the different systems was carried out. Finally, these DESs were applied to analyse the solubility of the following active principles: caffeine (Class I) and furosemide (Class IV) of the Biopharmaceutics Classification System (BCS). The selection of the drugs attends to different reasons. On one hand, we want to develop a new liquid formulation for model drug furosemide and, on the other hand, the study of caffeine, instead, will be used as a model for comparing purposes. Solubility results show that the systems that best solubilize caffeine are those with the highest water content; however, they do not reach the levels of solubility of pure water. On the other hand, for furosemide, a great increase in solubility was observed, especially for systems formed by xylitol and, fundamentally, in the system with the lowest water content. Obtaining an increase in solubility of up to 4530 times. These systems provide an opportunity to improve the formulation of drugs in the liquid medium of active ingredients that are poorly soluble in an aqueous medium.


Assuntos
Solventes Eutéticos Profundos , Açúcares , Solventes/química , Furosemida , Xilitol , Cafeína , Água/química , Solubilidade
5.
Curr Drug Deliv ; 18(9): 1303-1313, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33475061

RESUMO

BACKGROUND: A capsaicin cream was formulated by optimizing the rheological stability, the release behavior of the drug, and the pharmacological effect. OBJECTIVES: This study aimed to: (a) apply the Design of Experiment approach to study the rheological stability and release behaviors of a drug (capsaicin) from a formulated oil-in-water cream and (b) investigate the skin irritation and anti-inflammatory and analgesic effects of the optimized cream. METHODS: The cream prepared by the emulsification method was optimized using the central composite design, and then the pharmacological effect in experimental animals was determined using Complete Freund's adjuvant (CFA). RESULTS: The effects of a permeation enhancer (X1), Vaseline (X2), and surfactants (X3) on the fluctuation of the ratio of the viscous modulus (G ') to elastic modulus (G') (tan δ) after three cycles of cooling-heating (10-40°C), flux, and skin deposition of capsaicin after 8 h on mouse skin were statistically analyzed and optimized. The final obtained CAP-cream did not cause irritation in the rabbit model and produced comparable anti-inflammatory and analgesic effects to the reference product (Voltaren® emulgel). CONCLUSION: This study successfully integrated the DoE approach, rheological science, and pharmacological studies to develop a stable and highly effective semi-solid product containing capsaicin.


Assuntos
Analgésicos , Anti-Inflamatórios , Animais , Capsaicina , Camundongos , Coelhos , Reologia , Absorção Cutânea
6.
Int J Pharm ; 583: 119360, 2020 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-32335080

RESUMO

Extruded 3D printing is emerging as an attractive fabrication technology in the field of personalized oral medicines. The objective of this study was to develop a tunable extruded 3D printing platform based on thermo-sensitive gelatin pastes to meet the needs of achieving different drug release characteristics with flexible dosing and design. The printability and mechanisms of extrusion and deposition of the gelatin pastes were systematically studied. Ibuprofen and diclofenac sodium were used as model drugs for immediate- and sustained-release formulations, respectively. Following the optimization of formulation and process parameters, ibuprofen immediate-release formulations with different designs, and reservoir-type diclofenac sodium sustained-release formulations were printed. Target drug release patterns were successfully obtained for both model drugs. Rheological studies revealed that additives such as microcrystalline cellulose and hydroxypropyl methylcellulose can act as both thickeners and proppants of gelatin matrix. Furthermore, computational fluid dynamics simulation was used to visualize the printing process, and quantitatively analyze the influence of material viscosity, inlet velocity and nozzle diameter on the pressure and velocity of extrusion flow field. The present study demonstrated the great potential of extruded 3D printing technology using the thermo-sensitive gelatin paste platform for personalized oral medicines.


Assuntos
Gelatina/química , Impressão Tridimensional , Tecnologia Farmacêutica/métodos , Celulose/química , Preparações de Ação Retardada/química , Diclofenaco/química , Excipientes/química , Glicerol/química , Hidrodinâmica , Derivados da Hipromelose/química , Ibuprofeno/química , Lactose/química , Manitol/química , Reologia , Viscosidade , Água/química
7.
Int J Biol Macromol ; 106: 507-515, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-28801094

RESUMO

The objective of the study was to evaluate the effect of irradiation (0-5 kGy) on the physicochemical properties of two seed gums (guar and locust bean gum). The Hunter color parameters changed upon irradiation, namely "L" value decreased, whereas "a" and "b" values, i.e. redness and yellowness, increased. Irradiation reduced the final viscosity of gums at neutral and acidic pH. Increase in irradiation dose (0-5 kGy) increased the water absorption in the range of 11.75-14.61g/g and 20.04-23.99g/g in guar gum and locust bean gum, respectively. Rheological study of the gums revealed their gel behaviour with higher values of G' than G". G' in native guar gum was observed to increase in the range of 880.39-1332.29Pa while G" increased in the range of 194.21-239.77Pa as the test frequency was raised from 14.6-100s-1. In native locust bean gum, the G' and G" varied in the range of 476.50-1230.50Pa and 300.65-380.30Pa, respectively, under the applied frequency sweep. FT-IR revealed the presence of CH, COOH and CO groups in the guar as well as locust bean gum, in addition to the uronic acid and pyranose rings. The absorption of the functional groups declined upon irradiation.


Assuntos
Cyamopsis/química , Fabaceae/química , Galactanos/efeitos da radiação , Mananas/efeitos da radiação , Gomas Vegetais/efeitos da radiação , Sementes/química , Relação Dose-Resposta à Radiação , Galactanos/química , Raios gama , Concentração de Íons de Hidrogênio , Mananas/química , Gomas Vegetais/química , Reologia/efeitos da radiação , Viscosidade/efeitos da radiação
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