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1.
Pharmaceutics ; 15(12)2023 Dec 08.
Artigo em Inglês | MEDLINE | ID: mdl-38140088

RESUMO

Cannabigerol (CBG), a cannabinoid from Cannabis sativa L., recently attracted noteworthy attention for its dermatological applications, mainly due to its anti-inflammatory, antioxidant, and antimicrobial effectiveness similar to those of cannabidiol (CBD). In this work, based on results from studies of in vitro permeation through biomimetic membranes performed with CBG and CBD in the presence and in the absence of a randomly substituted methyl-ß-cyclodextrin (MßCD), a new CBG extemporaneous emulgel (oil-in-gel emulsion) formulation was developed by spray-drying. The powder (SDE) can be easily reconstituted with purified water, leading to a product with chemical-physical and technological characteristics that are comparable to those of the starting emulgels (E). Thermogravimetric analysis (TGA), attenuated total reflection-Fourier transformed infrared spectroscopy (ATR-FTIR), x-ray powder diffraction (XRPD), and high-performance liquid chromatography (HPLC) analyses demonstrated that the spray-drying treatment did not alter the chemical properties of CBG. This product can represent a metered-dosage form for the localized treatment of cutaneous afflictions such as acne and psoriasis.

2.
Bioact Mater ; 29: 16-35, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37456581

RESUMO

Neurodegenerative diseases represent a growing burden on healthcare systems worldwide. Mesenchymal stem cells (MSCs) have shown promise as a potential therapy due to their neuroregenerative, neuroprotective, and immunomodulatory properties, which are, however, linked to the bioactive substances they release, collectively known as secretome. This paper provides an overview of the most recent research on the safety and efficacy of MSC-derived secretome and extracellular vesicles (EVs) in clinical (if available) and preclinical models of Alzheimer's disease, Parkinson's disease, amyotrophic lateral sclerosis, multiple sclerosis, Huntington's disease, acute ischemic stroke, and spinal cord injury. The article explores the biologically active substances within MSC-secretome/EVs, the mechanisms responsible for the observed therapeutic effects, and the strategies that may be used to optimize MSC-secretome/EVs production based on specific therapeutic needs. The review concludes with a critical discussion of current clinical trials and a perspective on potential future directions in translating MSC-secretome and EVs into the clinic, specifically regarding how to address the challenges associated with their pharmaceutical manufacturing, including scalability, batch-to-batch consistency, adherence to Good Manufacturing Practices (GMP) guidelines, formulation, and storage, along with quality controls, access to the market and relative costs, value for money and impact on total expenditure.

3.
Gels ; 9(3)2023 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-36975704

RESUMO

The ionotropic gelation technique was chosen to produce vitamin D3-loaded microparticles starting from oil-in-water (O/W) Pickering emulsion stabilized by flaxseed flour: the hydrophobic phase was a solution of vitamin D3 in a blend of vegetable oils (ω6:ω3, 4:1) composed of extra virgin olive oil (90%) and hemp oil (10%); the hydrophilic phase was a sodium alginate aqueous solution. The most adequate emulsion was selected carrying out a preliminary study on five placebo formulations which differed in the qualitative and quantitative polymeric composition (concentration and type of alginate selected). Vitamin D3-loaded microparticles in the dried state had a particle size of about 1 mm, 6% of residual water content and excellent flowability thanks to their rounded shape and smooth surface. The polymeric structure of microparticles demonstrated to preserve the vegetable oil blend from oxidation and the integrity of vitamin D3, confirming this product as an innovative ingredient for pharmaceutical and food/nutraceutical purposes.

4.
Pharmaceutics ; 14(12)2022 Dec 14.
Artigo em Inglês | MEDLINE | ID: mdl-36559298

RESUMO

Spray congealing technique was exploited to produce solid lipid microparticles (SLMp) loaded with a highly water-soluble drug (metoclopramide hydrochloride) dissolved in the aqueous phase of a water in oil (W/O) emulsion. The use of an emulsion as starting material for a spray congealing treatment is not so frequent. Moreover, for this application, a W/O emulsion with a drug dissolved in water is a totally novel path. A ternary diagram was built to optimize the emulsion composition, a factorial design was used to identify the factors affecting the properties of the microparticles and a Design of Experiment strategy was applied to define the impact of process conditions and formulation variables on the SLMp properties. SLMp were characterized by particle size distribution, morphology, residual moisture, drug content, release behavior, FT-IR analysis and XRPD. The obtained microparticles presented a spherical shape, particle size distribution between 54-98 µm depending on atomizing pressure used during the production step and 2-5% residual moisture 4 days after the preparation. XRPD analysis revealed that lipid polymorphic transition alfa-beta occurs depending on the presence of water. In vitro drug release tests highlighted that all the formulations had a reduced release rate compared to the drug alone. These results suggest that spray congealing of a W/O emulsion could be proposed as a good strategy to obtain SLMp with a high loading of a hydrophilic drug and able to control its release rate.

5.
Pharmaceutics ; 14(2)2022 Jan 27.
Artigo em Inglês | MEDLINE | ID: mdl-35214029

RESUMO

The use of design space (DS) is a key milestone in the quality by design (QbD) of pharmaceutical processes. It should be considered from early laboratory development to industrial production, in order to support scientists with making decisions at each step of the product's development life. Presently, there are no available data or methodologies for developing models for the implementation of design space (DS) on laboratory-scale spray dryers. Therefore, in this work, a comparison between two different modeling approaches, thermodynamics and computational fluid dynamics (CFD), to a laboratory spray dryer model have been evaluated. The models computed the outlet temperature (Tout) of the process with a new modeling strategy that includes machine learning to improve the model prediction. The model metrics calculated indicate how the thermodynamic model fits Tout data better than CFD; indeed, the error of the CFD model increases towards higher values of Tout and feed rate (FR), with a final mean absolute error of 10.43 K, compared to the 1.74 K error of the thermodynamic model. Successively, a DS of the studied spray dryer equipment has been implemented, showing how Tout is strongly affected by FR variation, which accounts for about 40 times more than the gas flow rate (Gin) in the DS. The thermodynamic model, combined with the machine learning approach here proposed, could be used as a valid tool in the QbD development of spray-dried pharmaceutical products, starting from their early laboratory stages, replacing traditional trial-and-error methodologies, preventing process errors, and helping scientists with the following scale-up.

6.
Gels ; 7(4)2021 Oct 03.
Artigo em Inglês | MEDLINE | ID: mdl-34698156

RESUMO

Peppermint essential oil is encapsulated by inverse ionotropic gelation in core-shell systems, composed of alginate (ALG) alone or alginate with shellac gum (SHL) and/or carrageenan (CRG). A mixture design approach is used to evaluate the correlation between the formulation composition and some properties of the final products. Immediately after the preparation, capsules appear rounded with a smooth and homogeneous surface, having a similar particle size ranging from 3.8 mm to 4.5 mm. The drying process, carried out at 40 °C in an oven for 3 h, reduces capsules' diameters by at least 50% and has a negative impact on the shape of the systems because they lose their regular shape and their external membrane partially collapses. The peppermint essential oil content of dried capsules is between 14.84% and 33.75%. The swelling behaviour of the systems is affected by the composition of their outer shell. When the external membrane is composed of alginate and shellac gum, the capsule ability to swell is lower than that of the systems containing alginate alone. The swelling ratio reaches 31% for alginate capsules but does not exceed 21% if shellac is present. Differently, when the second polymer of the shell is carrageenan, the swelling ability increases as a function of polymer concentration and the swelling ratio reaches 360%. In the case of systems whose outer membrane is a polymeric ternary mixture, the swelling capacity increases or decreases according to the concentrations of the individual polymers. The obtained results suggest that carrageenan could be a useful excipient to increase the swelling behaviour of the systems, while shellac gum makes the system shell more hydrophobic. The use of a mixture design (i.e., the use of ternary diagrams and related calculations), in which each single component is chosen to provide specific properties to the final mixture, could be the right approach to develop improved formulations with a tailored essential oil release profile.

7.
Pharmaceutics ; 13(8)2021 Jul 23.
Artigo em Inglês | MEDLINE | ID: mdl-34452088

RESUMO

Producing mesenchymal stem cell (MSC)-secretome for dose escalation studies and clinical practice requires scalable and good manufacturing practice (GMP)-compliant production procedures and formulation into a standardized medicinal product. Starting from a method that combines ultrafiltration and freeze-drying to transform MSC-secretome into a pharmaceutical product, the lyosecretome, this work aims to: (i) optimize the lyosecretome formulation; (ii) investigate sources of variability that can affect the robustness of the manufacturing process; (iii) modify the ultrafiltration step to obtain a more standardized final product. Design of experiments and principal component analysis of the data were used to study the influence of batch production, lyophilization, mannitol (M)/sucrose (S) binary mixture, selected as cryoprotectant excipients, and the total amount of excipients on the extracellular vesicles (EV) particle size, the protein and lipid content and the in vitro anti-elastase. The different excipients ratios did not affect residual moisture or EV particle size; simultaneously, proteins and lipids were better preserved in the freeze-dried product using the maximum total concentration of excipients (1.5% w/v) with a M:S ratio of about 60% w/w. The anti-elastase activity was instead better preserved using 0.5% w/w of M as excipient. The secretome batch showed to be the primary source of variability; therefore, the manufacturing process has been modified and then validated: the final product is now concentrated to reach a specific protein (and lipid) concentration instead of cell equivalent concentration. The new standardization approach led to a final product with more reproducible quali-quantitative composition and higher biological activity.

8.
Int J Mol Sci ; 22(16)2021 Aug 06.
Artigo em Inglês | MEDLINE | ID: mdl-34445150

RESUMO

Titanium is one of the most frequently used materials in bone regeneration due to its good biocompatibility, excellent mechanical properties, and great osteogenic performance. However, osseointegration with host tissue is often not definite, which may cause implant failure at times. The present study investigates the capacity of the mesenchymal stem cell (MSC)-secretome, formulated as a ready-to-use and freeze-dried medicinal product (the Lyosecretome), to promote the osteoinductive and osteoconductive properties of titanium cages. In vitro tests were conducted using adipose tissue-derived MSCs seeded on titanium cages with or without Lyosecretome. After 14 days, in the presence of Lyosecretome, significant cell proliferation improvement was observed. Scanning electron microscopy revealed the cytocompatibility of titanium cages: the seeded MSCs showed a spread morphology and an initial formation of filopodia. After 7 days, in the presence of Lyosecretome, more frequent and complex cellular processes forming bridges across the porous surface of the scaffold were revealed. Also, after 14 and 28 days of culturing in osteogenic medium, the amount of mineralized matrix detected by alizarin red was significantly higher when Lyosecretome was used. Finally, improved osteogenesis with Lyosecretome was confirmed by confocal analysis after 28 and 56 days of treatment, and demonstrating the production by osteoblast-differentiated MSCs of osteocalcin, a specific bone matrix protein.


Assuntos
Regeneração Óssea , Substitutos Ósseos/química , Células-Tronco Mesenquimais/citologia , Titânio/química , Proliferação de Células , Células Cultivadas , Liofilização , Humanos , Células-Tronco Mesenquimais/metabolismo , Osteogênese , Alicerces Teciduais/química
9.
Pharmaceuticals (Basel) ; 14(3)2021 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-33803976

RESUMO

Sericin is a protein extracted from Bombyx mori silk cocoons. Over the last decade, this wastewater product of the textile industry has shown many interesting biological properties. This protein is widely used in the cosmetic and biomedical fields. In this study, sericin has been obtained via a High-Temperature High-Pressure degumming process, and was dried using the freeze-drying (fd) and spray-drying (sd) techniques. Proteins tend to collapse during drying, hence, sericin has been dried in the presence of two selected carrier agents: methyl-ß-cyclodextrin and trehalose. The obtained powders have been analyzed using thermal investigation, microscopy (optical, SEM), and granulometric and spectroscopic analyses. Moreover, the percentage yield of the spray-drying process has been calculated. Both the agents were able to significantly improve the drying process, without altering the physico-chemical properties of the protein. In particular, the co-spray-drying of sericin with methyl-ß-cyclodextrin and trehalose gave good process yields and furnished a powder with low moisture content and handling properties that are better than those of the other studied dried products. These characteristics seem to be appropriate and fruitful for the manufacturing of cosmetic raw materials.

10.
Int J Biol Macromol ; 162: 1293-1302, 2020 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-32585275

RESUMO

Encapsulation of essential oils represents a good strategy to protect and to transform them in free-flowing particles. Core-shell systems containing peppermint essential oil have been obtained by inverse ionotropic gelation. An O/W emulsion composed of essential oil (O) and aqueous CaCl2 solution enriched with hydroxyethylcellulose (W) was dripped in an alginate solution added of a secondary excipient (maltodextrin or shellac gum) at two concentrations. The qualitative/quantitative modifications of capsule shell composition had a limited impact on the essential oil content (it was more than 50% w/w), while they affected other dried capsule properties like dimensions, shell thickness, hardness and swelling behavior. Neither the type nor the amount of secondary excipient influenced wet capsule particle size (about 4 mm). After drying, particle size decreased (it was about 2 mm) and while shellac gum amount did not affect dried capsule dimensions, an increase in maltodextrin amount corresponded to an increase in their diameters. Capsule hardness diminished by increasing the amount of secondary excipient in the formulations. In addition, the amount of maltodextrin included in the formulations affected the swelling behavior of the dried capsules in water and this leads considering maltodextrin a useful excipient to modulate swelling according to the needs of the different applications.


Assuntos
Alginatos/química , Mentha piperita/química , Óleos Voláteis/química , Óleos de Plantas/química , Polissacarídeos/química , Resinas Vegetais/química , Cápsulas
11.
J Pharm Sci ; 107(2): 543-549, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-28947337

RESUMO

Two crystalline forms of tasimelteon, a drug approved by the U.S. Food and Drug Administration for the treatment of non-24-h sleep-wake disorder, have been studied by single crystal and powder diffraction analyses, thermogravimetric analysis, differential scanning calorimetry, spectroscopic, and optical methods. The synthetic method forming tasimelteon is described in detail, with its full analytical, spectroscopic, and enantiopurity characterization. Solid tasimelteon hemihydrate, C15H19NO2·0.5H2O, is tetragonal with a = b = 7.3573(2) Å, c = 52.062(2) Å, V = 2818.1(2) Å3; Z = 8. Its crystal structure has been solved and refined in the P43212 space group, showing the occurrence of polymeric (H-bonded) slabs, thanks to the presence of water molecule (OW) tetrahedrally linked to 4 distinct tasimelteon molecules in a N2(OW)O2 fashion. The anhydrous form of tasimelteon, C15H19NO2, crystallizes in the monoclinic P21 space group, with a = 11.130(4), b = 4.907(2), c = 12.230(6) Å, ß = 91.03(3)°, V = 667.8(5) Å3; Z = 2. Thanks to the availability of good-quality specimens, the structure of the latter phase was solved by conventional single-crystal diffraction analysis, showing short intermolecular C=O…H-N interactions between (translationally related) tasimelteon molecules, forming, in the crystal, well-defined chains running along the b axis. The morphology of the 2 crystal forms has been analyzed by the means of optical microscopy and particle size distribution analysis. Worthy of note, the newly determined crystal structures enable the successful usage of full-pattern matching X-ray-based quantitative analyses of batches of industrial interest, in search for contamination or phase stability issues.


Assuntos
Benzofuranos/química , Ciclopropanos/química , Melatonina/agonistas , Varredura Diferencial de Calorimetria/métodos , Cristalização/métodos , Cristalografia por Raios X/métodos , Tamanho da Partícula , Difração de Pó/métodos , Termogravimetria/métodos , Água/química , Difração de Raios X/métodos
12.
J Pharm Sci ; 105(11): 3351-3358, 2016 11.
Artigo em Inglês | MEDLINE | ID: mdl-27653554

RESUMO

The formulation and the coating composition of biopolymeric pellets containing ranolazine were studied to improve their technological and biopharmaceutical properties. Eudragit L100 (EU L100) and Eudragit L30 D-55-coated alginate and alginate-hydroxypropylcellulose (HPC) pellets were prepared by ionotropic gelation using 3 concentrations of HPC (0.50%, 0.65%, and 1.00% wt/wt) and applying different percentages (5%, 10%, 20%, and 30% wt/wt) of coating material. The uncoated pellets were regular in shape and had mean diameter between 1490 and 1570 µm. The rate and the entity of the swelling process were affected by the polymeric composition: increasing the HPC concentration, the structure of the pellets became more compact and slowed down the penetration of fluids. Coated alginate-HPC formulations were able to control the drug release at neutral pH: a higher quantity of HPC in the system determined a slower release of the drug. The nature of the coating polymer and the coating level applied affected the drug release in acidic environment: EU L100 gave better performance than Eudragit L30 D-55 and the best coating level was 20%. The pellets containing 0.65% of HPC and coated with 20% EU L100 represented the best formulation, able to limit the drug release in acidic environment and to control it at pH 6.8.


Assuntos
Alginatos/química , Celulose/análogos & derivados , Química Farmacêutica/métodos , Implantes de Medicamento/química , Ranolazina/química , Alginatos/farmacocinética , Fármacos Cardiovasculares/química , Fármacos Cardiovasculares/farmacocinética , Celulose/química , Celulose/farmacocinética , Portadores de Fármacos/química , Portadores de Fármacos/farmacocinética , Composição de Medicamentos , Implantes de Medicamento/farmacocinética , Liberação Controlada de Fármacos , Ácido Glucurônico/química , Ácido Glucurônico/farmacocinética , Ácidos Hexurônicos/química , Ácidos Hexurônicos/farmacocinética , Metacrilatos/química , Metacrilatos/farmacocinética , Polímeros/química , Polímeros/farmacocinética , Ácidos Polimetacrílicos/química , Ácidos Polimetacrílicos/farmacocinética , Ranolazina/farmacocinética
13.
Scientifica (Cairo) ; 2016: 5062706, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27127680

RESUMO

In this work alginate and alginate-chitosan beads containing celecoxib solubilized into a self-emulsifying phase were developed in order to obtain a drug delivery system for oral administration, able to delay the drug release in acidic environment and to promote it in the intestinal compartment. The rationale of this work was linked to the desire to improve celecoxib therapeutic effectiveness reducing its gastric adverse effects and to favor its use in the prophylaxis of colon cancer and as adjuvant in the therapy of familial polyposis. The systems were prepared by ionotropic gelation using needles with different diameters (400 and 600 µm). Morphology, particle size, swelling behavior, and in vitro drug release performance of the beads in aqueous media with different pH were investigated. The experimental results demonstrated that the presence of chitosan in the formulation caused an increase of the mechanical resistance of the bead structure and, as a consequence, a limitation of the bead swelling ability and a decrease of the drug release rate at neutral pH. Alginate-chitosan beads could be a good tool to guarantee a celecoxib colon delivery.

14.
Int J Pharm ; 499(1-2): 74-80, 2016 Feb 29.
Artigo em Inglês | MEDLINE | ID: mdl-26721727

RESUMO

In this work, alginate, alginate-pectin and alginate-hydroxypropylcellulose pellets were produced by ionotropic gelation and characterized. Ibuprofen was selected as model drug; it was suspended in the polymeric solution in crystalline form or dissolved in a self-emulsifying phase and then dispersed into the polymeric solution. The self-emulsifying excipient platform composed of Labrasol (PEG-8 caprylic/capric glycerides) and d-α-tocopherol polyethylene glycol 1000 succinate (TPGS), able to solubilize the drug was used to improve the technological and biopharmaceutical properties of the alginate pellets. The pellets had diameters between 1317 and 2026 µm and a high drug content (>51%). DSC analysis showed the amorphous state of drug in the pellets containing the self-emulsifying phase. All the systems restricted drug release in conditions simulating the gastric environment and made the drug completely available at a pH value typical for the intestine. Only alginate-HPC systems containing the drug solubilized into the self-emulsifying phase showed the ability to partially control the release of ibuprofen at neutral pH. The self-emulsifying excipient platform is a useful tool to improve technological and biopharmaceutical properties of alginate-HPC pellets.


Assuntos
Alginatos/química , Celulose/análogos & derivados , Excipientes/química , Ibuprofeno/administração & dosagem , Varredura Diferencial de Calorimetria , Celulose/química , Química Farmacêutica/métodos , Cristalização , Liberação Controlada de Fármacos , Emulsões , Ácido Glucurônico/química , Glicerídeos/química , Ácidos Hexurônicos/química , Concentração de Íons de Hidrogênio , Ibuprofeno/química , Tamanho da Partícula , Pectinas/química , Polietilenoglicóis/química , Solubilidade , Tecnologia Farmacêutica/métodos , Vitamina E/análogos & derivados , Vitamina E/química
15.
Pharm Dev Technol ; 20(2): 153-8, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24219826

RESUMO

The aim of the work was to realize itraconazole-loaded formulations in form of microparticles using a fast, simple and solvent free production procedure. The selected excipients were able to enhance wettability of the final product, to increase drug dissolution rate and to maintain drug in solution thanks to the formation of an emulsified system after contact with the gastrointestinal fluids. Itraconazole formulations contained a structuring lipid, a solubilizing agent and a surface active substance and were prepared by a hot melt method (MMS, melting-milling-sieving). The characterization included drug content determination, granulometric distribution, differential scanning calorimetry (DSC) and in vitro drug release test, physical and technological stability after 12 months of ambient condition storage. The formulations were composed of particles with diameter lower than 355 µm. DSC analysis evidenced that itraconazole was almost completely in the amorphous form; the results of the in vitro drug release tests showed that these formulations were able to increase the rate of the drug release compared to that of the free drug. Stability data showed no significant changes in the thermal and release profiles, confirming that the selected excipients protected the drug avoiding its conversion from amorphous state into crystalline form and maintaining unchanged the delivery behavior.


Assuntos
Itraconazol/química , Tecnologia Farmacêutica/métodos , Varredura Diferencial de Calorimetria , Cristalização , Composição de Medicamentos , Liberação Controlada de Fármacos , Estabilidade de Medicamentos , Armazenamento de Medicamentos , Excipientes/química , Tamanho da Partícula , Solubilidade , Propriedades de Superfície
16.
J Pharm Biomed Anal ; 102: 305-13, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25459928

RESUMO

Difluprednate, a FDA approved topical corticosteroid indicated for the treatment of inflammation and pain associated with ocular surgery, affords three polymorphic crystal forms (one hexagonal, sg. P65, and two distinct orthorhombic, both sg.'s P212121, phases), whose preparation, thermal stability ranges, crystal structures and stereochemical preferences are here reported. Using DSC, single-crystal structural analysis and less conventional ab-initio X-ray powder diffraction methods, the rich structural and thermal behavior of three difluprednate polymorphs have been clarified, and the validity of previous complex and sometimes contradicting literature reports has been challenged. Complementary solution state NMR provided (1)H, (13)C and (19)F chemical shifts full assignment of the corresponding signals. These results allow us to precisely describe the selective isolation pathways toward three distinct crystal phases, and to define their structural and analytical data necessary for identification and easy and accurate quantification, by modern Rietveld analysis, of complex difluprednate polymorphic mixtures, often obtained as a result of poorly controlled (co)-precipitation methods.


Assuntos
Fluprednisolona/análogos & derivados , Varredura Diferencial de Calorimetria , Cristalização , Fluprednisolona/química , Espectroscopia de Ressonância Magnética , Difração de Raios X
17.
Int J Pharm ; 473(1-2): 87-94, 2014 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-24971693

RESUMO

The work is aimed at investigating the polymorphism and the phase transition kinetics of binary lipid mixtures with potential application in controlled drug delivery. The lipid systems, constituted of glyceryl tristearate (GTS) added with different amounts (1.0-7.5% w/w) of a medium-chain liquid triglyceride (C10-C12 acyl derivative - MCT), were studied by differential scanning calorimetry, by X-ray diffraction and hot-stage microscopy. The liquid lipid, although present in small amount, modified the thermal profile and the diffraction pattern of the systems, indicating that it promoted the formation of the GTS stable polymorph, ß, during the re-solidification of the melted mixture. This promotion effect of MCT was concentration-dependent and evident for systems containing MCT>2.5%. Also the kinetics of transformation of GTS polymorphs was affected by the percentage of the liquid component. The α → ß-transition was a biphasic process which for GTS-MCT mixture (99:1) superimposed that of pure GTS, while followed a different trend for systems containing percentages of MCT higher than 2.5.


Assuntos
Triglicerídeos/química , Varredura Diferencial de Calorimetria , Cristalização , Cinética , Microscopia/métodos , Transição de Fase , Difração de Pó , Difração de Raios X
18.
Eur J Pharm Biopharm ; 82(3): 491-7, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22940572

RESUMO

VarioSol® is an innovative, solvent-free technology able to produce microparticles exploiting near-critical CO(2) properties as spraying and cooling agent. The aim of the present work was to evaluate the feasibility to produce in a single processing step by VarioSol® technology, oral ketoprofen-loaded microparticles with gastro-protective properties. The obtained products were powders composed of regular in shape and small in diameter microparticles, characterized by high drug content (40%) and good flow properties. Microparticles were composed by anionic lipids scarcely soluble at acidic pH, blended with gastro-resistant polymers of the methacrylate type. In vitro drug release results indicated that the drug was rapidly delivered from the microparticulate systems in phosphate buffer at pH 6.8, while in acidic medium, the microparticles were able to retard the drug release process but without reaching complete gastro-resistance. However, the results obtained in this study, although non optimal, are not far from the specifications required for gastro-resistant release products (i.e., no more than 10% drug released after 1h at pH 1.0) according to EMA guidelines and represent a good starting point for future formulation development.


Assuntos
Anti-Inflamatórios não Esteroides/administração & dosagem , Sistemas de Liberação de Medicamentos , Cetoprofeno/administração & dosagem , Ácidos Polimetacrílicos/química , Administração Oral , Anti-Inflamatórios não Esteroides/química , Dióxido de Carbono/química , Portadores de Fármacos/química , Estudos de Viabilidade , Guias como Assunto , Concentração de Íons de Hidrogênio , Cetoprofeno/química , Tamanho da Partícula , Tecnologia Farmacêutica , Fatores de Tempo
19.
J Pharm Sci ; 99(4): 2070-9, 2010 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-19780132

RESUMO

This article proposes thermogravimetric analysis (TGA) as a useful method to investigate the hydration behaviour of hydrophilic matrix tablets containing hydroxypropylmethylcellulose (HPMC), sodium carboxymethylcellulose (NaCMC) or a mixture of these two polymers and four drugs with different solubility. The hydration behaviour of matrix systems was studied as a function of the formulation composition and of the dissolution medium pH. TGA results suggest that the hydration of matrices containing HPMC is pH-independent and not affected by the characteristics of the loaded drug; this confirms HPMC as a good polymer to formulate controlled drug delivery systems. On the other hand, the performances of NaCMC matrix tablets are significantly affected by the medium pH and the hydration and swelling of this ionic polymer is influenced by the loaded drug. For systems containing the two polymers, HPMC plays a dominant role in the hydration/dissolution process at acidic pH, while at near neutral pH both the cellulose derivatives exert a significant influence on the hydration performance of systems. The results of this work show that TGA is able to give quantitative highlights on the hydration behaviour of polymeric materials; thus this technique could be a helpful tool to support conventional hydration/swelling/dissolution studies.


Assuntos
Carboximetilcelulose Sódica/química , Metilcelulose/análogos & derivados , Preparações Farmacêuticas/química , Comprimidos/química , Termogravimetria/métodos , Concentração de Íons de Hidrogênio , Derivados da Hipromelose , Metilcelulose/química , Solubilidade , Água/química
20.
Eur J Pharm Biopharm ; 65(2): 198-203, 2007 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-17008076

RESUMO

The Hot Air Coating (HAC) technique was used to prepare microparticles consisting of 30% nifedipine coated with different lipid mixtures. Cetearyl alcohol or cetearyl alcohol and 5% or 15% of a poloxamer (Pluronic F68 or Pluronic F127) were used as excipients. HAC products were analyzed in terms of morphology, flowability, thermal properties and nifedipine release behaviour, in order to elucidate the role played by the Pluronics on the physico-chemical and pharmaceutical characteristics of microparticles. HAC particles were spherical and their surface appeared scale-worked; thermal studies demonstrated the existence of relevant interactions among the system components and the dissolution experiments led to the hypothesis that the drug is released primarily by diffusion through the lipid coating: the poloxamer and its concentration have a significant influence on the pharmaceutical properties of the dosage form, as shown by the a parameter of Weibull model.


Assuntos
Nifedipino/administração & dosagem , Nifedipino/química , Poloxâmero/química , Tensoativos/química , Algoritmos , Varredura Diferencial de Calorimetria , Química Farmacêutica , Álcoois Graxos , Microscopia Eletrônica de Varredura , Nanopartículas , Solubilidade , Comprimidos com Revestimento Entérico
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