Search results for " Controlled release"

showing 3 items of 13 documents

Development and In Vitro Evaluation of Lyotropic Liquid Crystals for the Controlled Release of Dexamethasone.

2017

Made available in DSpace on 2018-12-11T17:33:26Z (GMT). No. of bitstreams: 0 Previous issue date: 2017-08-02 Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) In this study, amphiphilic polymers were investigated as biomaterials that can control dexamethasone (DXM) release. Such materials present interfacial properties in the presence of water and an oily phase that can result in lyotropic liquid crystalline systems (LLCS). In addition, they can form colloidal nanostructures similar to those in living organisms, such as bilayers and hexagonal and cubic phases, which can be exploited to solubilize lipophilic drugs to sustain their release and enhance bioavailability. It was…

Materials sciencePolymers and PlasticsAmphiphilic polymersdexamethasone02 engineering and technology030226 pharmacology & pharmacyArticleDexamethasonelcsh:QD241-44103 medical and health scienceschemistry.chemical_compound0302 clinical medicinelcsh:Organic chemistryLyotropicControlled releaseNanostructured systemsLamellar structurelyotropic liquid crystalsIsopropyl myristatedrug releasechemistry.chemical_classificationPolarized light microscopyChromatographySmall-angle X-ray scatteringfungiDrug releaseGeneral ChemistryPolymerkinetic modelKinetic modelamphiphilic polymers; lyotropic liquid crystals; controlled release; drug release; kinetic model; dexamethasone; nanostructured systems021001 nanoscience & nanotechnologyControlled releaseLyotropic liquid crystalschemistryChemical engineeringnanostructured systemsLyotropic liquid crystal0210 nano-technologycontrolled releaseamphiphilic polymersPolymers
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Incorporation of nisin in poly (ethylene-co-vinyl acetate) films by melt processing: a study on the antimicrobial properties

2011

Both industry and academia have shown a growing interest in materials with antimicrobial properties suitable for food packaging applications. In this study, we prepared and characterized thin films of ethylene-co-vinyl acetate (EVA) copolymer with antimicrobial properties. The films were prepared with a film blowing process by incorporating a nisin preparation as an antimicrobial agent in the melt. Two grades of EVA containing 14 and 28% (wt/wt) vinyl acetate (EVA 14 and EVA 28, respectively) and two commercial formulations of nisin with different nominal activities were used. The effect of the nisin concentration also was evaluated. The films with the highest antimicrobial activity were th…

Materials scienceEthyleneTime FactorsFood ContaminationBacterial Physiological PhenomenaMicrobiologychemistry.chemical_compoundBacteriocinotorhinolaryngologic diseasesCopolymerVinyl acetateOrganic chemistryHumansNisinNisinPoly ethyleneDose-Response Relationship DrugFood PackagingTemperatureAntimicrobialAnti-Bacterial AgentsFood packagingchemistryConsumer Product SafetyBiofilmsFood MicrobiologyEVA antimicrobial properties nisin melt processing controlled releasePolyvinylsFood ScienceNuclear chemistry
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Not always what closes best opens better: mesoporous nanoparticles capped with organic gates

2019

ABSTRACT Four types of calcined MCM-41 silica nanoparticles, loaded with dyes and capped with different gating ensembles are prepared and characterized. N1 and N2 nanoparticles are loaded with rhodamine 6G and capped with bulky poly(ethylene glycol) derivatives bearing ester groups (1 and 2). N3-N4 nanoparticles are loaded with sulforhodamine B and capped with self-immolative derivatives bearing ester moieties. In the absence of esterase enzyme negligible cargo release from N1, N3 and N4 nanoparticles is observed whereas a remarkable release for N2 is obtained most likely due to the formation of an irregular coating on the outer surface of the nanoparticles. In contrast, a marked delivery i…

Materials science102 Porous / Nanoporous / Nanostructured materialslcsh:BiotechnologyNanoparticle02 engineering and technologyGating010402 general chemistryEngineering and Structural Materials01 natural scienceslaw.inventionSilica nanoparticlesRhodamine 6Gchemistry.chemical_compoundlaw10 Engineering and Structural materialslcsh:TP248.13-248.65lcsh:TA401-492General Materials ScienceCalcinationgated nanodevices021001 nanoscience & nanotechnologyesterase controlled release0104 chemical sciencesChemical engineeringchemistrylcsh:Materials of engineering and construction. Mechanics of materials0210 nano-technologyMesoporous materialmesoporous nanoparticles
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