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1.
Polymers (Basel) ; 15(17)2023 Aug 31.
Artículo en Inglés | MEDLINE | ID: mdl-37688241

RESUMEN

Micro- and nanotechnologies have been intensively studied in recent years as novel platforms for targeting and controlling the delivery of various pharmaceutical substances. Microparticulate drug delivery systems for oral, parenteral, or topical administration are multiple unit formulations, considered as powerful therapeutic tools for the treatment of various diseases, providing sustained drug release, enhanced drug stability, and precise dosing and directing the active substance to specific sites in the organism. The properties of these pharmaceutical formulations are highly dependent on the characteristics of the polymers used as drug carriers for their preparation. Starch and cellulose are among the most preferred biomaterials for biomedical applications due to their biocompatibility, biodegradability, and lack of toxicity. These polysaccharides and their derivatives, like dextrins (maltodextrin, cyclodextrins), ethylcellulose, methylcellulose, hydroxypropyl methylcellulose, carboxy methylcellulose, etc., have been widely used in pharmaceutical technology as excipients for the preparation of solid, semi-solid, and liquid dosage forms. Due to their accessibility and relatively easy particle-forming properties, starch and cellulose are promising materials for designing drug-loaded microparticles for various therapeutic applications. This study aims to summarize some of the basic characteristics of starch and cellulose derivatives related to their potential utilization as microparticulate drug carriers in the pharmaceutical field.

2.
Pharmaceutics ; 15(8)2023 Aug 11.
Artículo en Inglés | MEDLINE | ID: mdl-37631340

RESUMEN

The main goal of modern pharmaceutical technology is to create new drug formulations that are safer and more effective. These formulations should allow targeted drug delivery, improved drug stability and bioavailability, fewer side effects, and reduced drug toxicity. One successful approach for achieving these objectives is using polymer microcarriers for drug delivery. They are effective for treating various diseases through different administration routes. When creating pharmaceutical systems, choosing the right drug carrier is crucial. Biomaterials have become increasingly popular over the past few decades due to their lack of toxicity, renewable sources, and affordability. Marine polysaccharides, in particular, have been widely used as substitutes for synthetic polymers in drug carrier applications. Their inherent properties, such as biodegradability and biocompatibility, make marine polysaccharide-based microcarriers a prospective platform for developing drug delivery systems. This review paper explores the principles of microparticle design using marine polysaccharides as drug carriers. By reviewing the current literature, the paper highlights the challenges of formulating polymer microparticles, and proposes various technological solutions. It also outlines future perspectives for developing marine polysaccharides as drug microcarriers.

3.
Polymers (Basel) ; 15(15)2023 Jul 29.
Artículo en Inglés | MEDLINE | ID: mdl-37571136

RESUMEN

Fucoidan belongs to the family of marine sulfated, L-fucose-rich polysaccharides found in the cell wall matrix of various brown algae species. In the last few years, sulfated polysaccharides have attracted the attention of researchers due to their broad biological activities such as anticoagulant, antithrombotic, antidiabetic, immunomodulatory, anticancer and antiproliferative effects. Recently the application of fucoidan in the field of pharmaceutical technology has been widely investigated. Due to its low toxicity, biocompatibility and biodegradability, fucoidan plays an important role as a drug carrier for the formulation of various drug delivery systems, especially as a biopolymer with anticancer activity, used for targeted delivery of chemotherapeutics in oncology. Furthermore, the presence of sulfate residues with negative charge in its structure enables fucoidan to form ionic complexes with oppositely charged molecules, providing relatively easy structure-forming properties in combination with other polymers. The aim of the present study was to overview essential fucoidan characteristics, related to its application in the development of pharmaceutical formulations as a single drug carrier or in combinations with other polymers. Special focus was placed on micro- and nanosized drug delivery systems with polysaccharides and their application in the field of oncology.

4.
Mar Drugs ; 21(4)2023 Apr 16.
Artículo en Inglés | MEDLINE | ID: mdl-37103384

RESUMEN

The aim of this study was to identify the chemical composition and sequential structure of alginate isolated from C. crinita harvested in the Bulgarian Black Sea, as well as its effects in histamine-induced paw inflammation in rats. The serum levels of TNF-α, IL-1ß, IL-6, and IL-10 in rats with systemic inflammation, and the levels of TNF-α in a model of acute peritonitis in rats were also investigated. The structural characterization of the polysaccharide was obtained by FTIR, SEC-MALS, and 1H NMR. The extracted alginate had an M/G ratio of 1.018, a molecular weight of 7.31 × 104 g/mol, and a polydispersity index of 1.38. C. crinita alginate in doses of 25 and 100 mg/kg showed well-defined anti-inflammatory activity in the model of paw edema. A significant decrease in serum levels of IL-1ß was observed only in animals treated with C. crinita alginate in a dose of 25 mg/kg bw. The concentrations of TNF-α and IL-6 in serum were significantly reduced in rats treated with both doses of the polysaccharide, but no statistical significance was observed in the levels of the anti-inflammatory cytokine IL-10. A single dose of alginate did not significantly alter the levels of the pro-inflammatory cytokine TNF-α in the peritoneal fluid of rats with a model of peritonitis.


Asunto(s)
Peritonitis , Phaeophyceae , Ratas , Animales , Alginatos/efectos adversos , Interleucina-10 , Factor de Necrosis Tumoral alfa , Interleucina-6 , Mar Negro , Bulgaria , Antiinflamatorios , Citocinas , Inflamación/inducido químicamente , Inflamación/tratamiento farmacológico , Peritonitis/inducido químicamente , Peritonitis/tratamiento farmacológico , Polisacáridos/química , Edema/tratamiento farmacológico
5.
Viruses ; 14(2)2022 02 18.
Artículo en Inglés | MEDLINE | ID: mdl-35216019

RESUMEN

In the current context of the COVID-19 pandemic, it appears that our scientific resources and the medical community are not sufficiently developed to combat rapid viral spread all over the world. A number of viruses causing epidemics have already disseminated across the world in the last few years, such as the dengue or chinkungunya virus, the Ebola virus, and other coronavirus families such as Middle East respiratory syndrome (MERS-CoV) and severe acute respiratory syndrome (SARS-CoV). The outbreaks of these infectious diseases have demonstrated the difficulty of treating an epidemic before the creation of vaccine. Different antiviral drugs already exist. However, several of them cause side effects or have lost their efficiency because of virus mutations. It is essential to develop new antiviral strategies, but ones that rely on more natural compounds to decrease the secondary effects. Polysaccharides, which have come to be known in recent years for their medicinal properties, including antiviral activities, are an excellent alternative. They are essential for the metabolism of plants, microorganisms, and animals, and are directly extractible. Polysaccharides have attracted more and more attention due to their therapeutic properties, low toxicity, and availability, and seem to be attractive candidates as antiviral drugs of tomorrow.


Asunto(s)
Antivirales/química , Antivirales/farmacología , Polisacáridos/química , Polisacáridos/farmacología , Virus/efectos de los fármacos , Animales , Brotes de Enfermedades/prevención & control , Ebolavirus/efectos de los fármacos , Humanos , SARS-CoV-2/efectos de los fármacos , Virosis/tratamiento farmacológico , Replicación Viral/efectos de los fármacos , Virus/clasificación , Virus/patogenicidad
6.
Molecules ; 26(24)2021 Dec 09.
Artículo en Inglés | MEDLINE | ID: mdl-34946549

RESUMEN

Essential oils have been studied for various applications, including for therapeutic purposes. There is extensive literature regarding their properties; however, their low stability limits their application. Generally, the microencapsulation of essential oils allows enhanced stability and enables the potential incorporation in solid dosage forms. Lavender and peppermint oils were encapsulated in microparticles using a spray-drying technique under optimized conditions: 170 °C temperature, 35 m3/h aspiration volume flow, and 7.5 mL/min feed flow. Arabic gum and maltodextrin were used as coating polymers individually in varying concentrations from 5 to 20% (w/v) and in combination. The microparticles were studied for morphology, particle size, oil content, and flowability. The formulated powder particles showed a high yield of 71 to 84%, mean diameter 2.41 to 5.99 µm, and total oil content of up to 10.80%. The results showed that both the wall material type and concentration, as well as the type of essential oil, significantly affected the encapsulation process and the final particle characteristics. Our study has demonstrated that the encapsulation of lavender and peppermint oils in Arabic gum/maltodextrin microparticles by spray-drying represents a feasible approach for the conversion of liquids into solids regarding their further use in powder technology.


Asunto(s)
Desecación , Composición de Medicamentos , Lavandula/química , Mentha piperita/química , Aceites Volátiles/química , Cápsulas
7.
Polymers (Basel) ; 13(19)2021 Sep 29.
Artículo en Inglés | MEDLINE | ID: mdl-34641160

RESUMEN

The intensive development of micro- and nanotechnologies in recent years has offered a wide horizon of new possibilities for drug delivery in dentistry. The use of polymeric drug carriers turned out to be a very successful technique for formulating micro- and nanoparticles with controlled or targeted drug release in the oral cavity. Such innovative strategies have the potential to provide an improved therapeutic approach to prevention and treatment of various oral diseases not only for adults, but also in the pediatric dental practice. Due to their biocompatibility, biotolerance and biodegradability, naturally occurring polysaccharides like chitosan, alginate, pectin, dextran, starch, etc., are among the most preferred materials for preparation of micro- and nano-devices for drug delivery, offering simple particle-forming characteristics and easily tunable properties of the formulated structures. Their low immunogenicity and low toxicity provide an advantage over most synthetic polymers for the development of pediatric formulations. This review is focused on micro- and nanoscale polysaccharide biomaterials as dental drug carriers, with an emphasis on their potential application in pediatric dentistry.

8.
Polymers (Basel) ; 12(10)2020 Oct 13.
Artículo en Inglés | MEDLINE | ID: mdl-33066186

RESUMEN

Inflammation is the initial response of the immune system to potentially harmful stimuli (e.g., injury, stress, and infections). The process involves activation of macrophages and neutrophils, which produce mediators, such as nitric oxide (NO), prostaglandin E2 (PGE2), pro-inflammatory and anti-inflammatory cytokines. The pro-inflammatory cytokines interleukin-1ß (IL-1ß), interleukin 6 (IL-6), and tumor necrosis factor-α (TNF-α) are considered as biomarkers of inflammation. Even though it occurs as a physiological defense mechanism, its involvement in the pathogenesis of various diseases is reported. Rheumatoid arthritis, inflammatory bowel disease, Alzheimer's disease, and cardiovascular diseases are only a part of the diseases, in which pathogenesis the chronic inflammation is involved. Fucoidans are complex polysaccharides from brown seaweeds and some marine invertebrates, composed mainly of L-fucose and sulfate ester groups and minor amounts of neutral monosaccharides and uronic acids. Algae-derived fucoidans are studied intensively during the last years regarding their multiple biological activities and possible therapeutic potential. However, the source, species, molecular weight, composition, and structure of the polysaccharides, as well as the route of administration of fucoidans, could be crucial for their effects. Fucoidan is reported to act on different stages of the inflammatory process: (i) blocking of lymphocyte adhesion and invasion, (ii) inhibition of multiple enzymes, and (iii) induction of apoptosis. In this review, we focused on the immunemodulating and anti-inflammatory effects of fucoidans derived from macroalgae and the models used for their evaluation. Additional insights on the molecular structure of the compound are included.

9.
Eur J Pharm Sci ; 123: 387-394, 2018 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-30077710

RESUMEN

Spray-dried chitosan microparticles have been widely exploited as vehicles for mucosal drug delivery. Despite their advantages as pharmaceutical formulations, one of the major challenges is achieving sustained drug release, which would diminish toxicity and dosage frequency. The aim of this study was to formulate mucoadhesive glutaraldehyde cross-linked chitosan microparticles loaded with doxylamine succinate and pyridoxine hydrochloride as potential nasal drug delivery systems with sustained release. Microparticle models were formulated via spray-drying technique, using glutaraldehyde in different concentrations (0.1-1.0 mg/mL) as a cross-linking agent for chitosan. The obtained particles were with spherical shape, smooth surface and median diameter of 4 µm. The drug entrapment efficiency was high (80.47%-94.25%), indicating a tendency to decrease at higher glutaraldehyde concentrations. FTIR data demonstrated that there were no chemical interactions between glutaraldehyde and the drugs. The in vitro studies showed that the cross-linking process substantially limited particles swelling. The cross-linked particles exhibited sustained drug release characteristics at pH 6.8 over a period of 5 h with an initial burst-effect in the first 30 min. Drug release followed Korsmeyer-Peppas kinetics. Although a decrease of the particles mucoadhesive properties was observed after modification, all cross-linked formulations demonstrated high in vitro adsorption of mucin. The proposed models of mucoadhesive microsphere with sustained drug release are a perspective ground for further development of a novel delivery system for nasal administration of doxylamine and pyridoxine.


Asunto(s)
Antieméticos/química , Química Farmacéutica/métodos , Quitosano/química , Reactivos de Enlaces Cruzados/química , Diciclomina/química , Doxilamina/química , Portadores de Fármacos , Glutaral/química , Piridoxina/química , Adhesividad , Administración Intranasal , Antieméticos/administración & dosificación , Preparaciones de Acción Retardada , Diciclomina/administración & dosificación , Doxilamina/administración & dosificación , Combinación de Medicamentos , Composición de Medicamentos , Liberación de Fármacos , Estudios de Factibilidad , Mucinas Gástricas/química , Cinética , Microesferas , Piridoxina/administración & dosificación , Solubilidad
10.
Acta Pharm ; 68(1): 61-73, 2018 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-29453910

RESUMEN

The prediction power of partial least squares (PLS) and multivariate curve resolution-alternating least squares (MCR-ALS) methods have been studied for simultaneous quantitative analysis of the binary drug combination - doxylamine succinate and pyridoxine hydrochloride. Analysis of first-order UV overlapped spectra was performed using different PLS models - classical PLS1 and PLS2 as well as partial robust M-regression (PRM). These linear models were compared to MCR-ALS with equality and correlation constraints (MCR-ALS-CC). All techniques operated within the full spectral region and extracted maximum information for the drugs analysed. The developed chemometric methods were validated on external sample sets and were applied to the analyses of pharmaceutical formulations. The obtained statistical parameters were satisfactory for calibration and validation sets. All developed methods can be successfully applied for simultaneous spectrophotometric determination of doxylamine and pyridoxine both in laboratory-prepared mixtures and commercial dosage forms.


Asunto(s)
Doxilamina/análogos & derivados , Piridoxina/química , Calibración , Doxilamina/química , Composición de Medicamentos/métodos , Análisis de los Mínimos Cuadrados , Análisis Multivariante , Espectrofotometría/métodos
11.
Folia Med (Plovdiv) ; 59(3): 310-317, 2017 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-28976898

RESUMEN

BACKGROUND: Generally, the preparation of spray-dried microspheres is strongly affected by the process parameters. Particle size and production yield are mainly influenced by the spraying solution concentration and the pump rate of the spray dryer. AIM: The aim of this study was to assess optimum spray drying parameters - polymer concentration and pump rate required for the production of chitosan microspheres with high production yield and targeted for nasal administration particle size. MATERIALS AND METHODS: Full 32 factorial design was used to study the investigated parameters. Three different concentrations of the chitosan solution were selected: a low concentration of 1%, average concentration of 1.5% and high concentration of 2%. The rate of the peristaltic pump was also varied at three levels: low rate of 10%, medium rate of 14% and high rate of 18%. RESULTS: Nine models of chitosan microspheres were formulated and characterized in terms of shape, surface morphology, size, particle size distribution and production yield. The particles obtained from 2% chitosan solutions, sprayed at 10% pump rate were of the highest yield (64.33%) and appropriate for nasal administration median diameter (3,434 µm). CONCLUSION: The two investigated spray-drying parameters interact with each other and their influence on the production yield and the size of the chitosan microspheres should be evaluated together, instead of one at a time. The assessed process parameters allow the production of chitosan microparticles with high yield and desirable characteristics (size, size distribution and shape) for intranasal delivery.


Asunto(s)
Quitosano/química , Portadores de Fármacos/farmacología , Microesferas , Sistemas de Liberación de Medicamentos , Diseño de Fármacos , Humanos , Técnicas In Vitro , Tamaño de la Partícula , Sensibilidad y Especificidad
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