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1.
Int J Pharm ; 501(1-2): 300-10, 2016 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-26873394

RESUMO

Extracellular biosynthesis of nanoparticles have many important advantages such as well dispersed in aqueous solutions, low energy requirements, ecofriendly, non-toxic, low-costs and non-flocculate. This technique have shown significant promise as targeted drug delivery applications. In this investigation, for the first time, we examine the efficacy of targeted therapeutic delivery with t-PA and SK immobilized to biosynthesis of nanoparticles (CuNP) by using Streptococcus equi strains isolated from the horses of Iran and their ability to produce metallic nanoparticles. Also we compared them with their chemical synthesis. The S. equi was screened for its ability to produce MNPs. The minimum size and shapes (23-89 nm) are presented in the formation with good dispersion and high stability. Response Surface methodology was applied for the optimized production of biological CuNPs. The growth factors like pH, temperature and incubation time was changed. The optimum conditions to obtain CuNPs were found with the culture conditions of pH 7.5 in 120 h at 35 °C. To determine some of MNPs structural properties UV-vis absorption spectrophotometer, FTIR, XRD and SEM has characterized. The results provided some parameters may impact on the formation of biological MNPs. Lastly, these MNPs were conjugated with t-PA and SK, as a drug carrier. In addition, effective thrombolysis with magnet-guided SiO2CuNPs-tPA-SK is demonstrated in rat embolism model where 18.6% of the regular t-PA dose and 15.78% of SK dose restored and 15-25 min reductions in blood clot lysis time were observed compared with runs with free t-PA and without magnet-guided and using the same drug dosage. The comparison between CuNPs with MNPs shows that thrombolysis had not been directed to the type of magnetic carrier under the magnetic guide.


Assuntos
Cobre , Nanopartículas Metálicas , Dióxido de Silício , Streptococcus equi , Estreptoquinase , Ativador de Plasminogênio Tecidual , Animais , Materiais Biocompatíveis/administração & dosagem , Materiais Biocompatíveis/química , Cobre/administração & dosagem , Cobre/química , Enzimas Imobilizadas/administração & dosagem , Enzimas Imobilizadas/química , Fibrinólise/efeitos dos fármacos , Concentração de Íons de Hidrogênio , Masculino , Nanopartículas Metálicas/administração & dosagem , Nanopartículas Metálicas/química , Ratos , Dióxido de Silício/administração & dosagem , Dióxido de Silício/química , Estreptoquinase/administração & dosagem , Estreptoquinase/química , Temperatura , Ativador de Plasminogênio Tecidual/administração & dosagem , Ativador de Plasminogênio Tecidual/química
2.
Int J Pharm ; 495(1): 428-438, 2015 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-26363110

RESUMO

Thrombolytic therapy for acute myocardial infarction standardly makes use of the medications streptokinase (SK) and tissue plasminogen activator (tPA). In this study, the potential of silica-coated magnetic nanoparticles (SiO2-MNPs) as nanocarriers clinical thrombolytic therapy was investigated. SiO2-MNPs for use in targeted therapeutic delivery of tPA and SK were prepared using a combined technique incorporating controlled precipitation and hydrothermal methods. Response surface methodology (RSM) was employed to evaluate the efficiency of the SiO2-MNPs. The production of SK secreted from Streptococcus equi was enhanced using random mutagenesis. The tPA and SK A were encapsulated by means of a silanizing agent with a surface rich in 3-aminopropyltrimethoxysilane layered around the SiO2-MNPs. Blood clot lysis assays and fibrin-containing agarose plates were used to carry out in vitro thrombolysis testing. The optimum conditions for producing MNPs were found to be at pH=13 and at a temperature of 75°C for 45 min. Culture conditions of 2.75% NaCl concentration at initial pH=7.5 for 90 s under UV resulted in maximum SK activity. The tPA/SK-conjugated SiO2-MNPs (SiO2-MNP-tPA-SK) increased operating stability in whole blood and storage stability in a buffer by 92%. More effective thrombolysis using magnetic targeting was indicated by a 38% reduction in blood clot lysis time achieved with SiO2-MNP-tPA-SK compared to administering the SiO2-MNPs without guidance. The silica-coated magnetic nanocarriers developed in this study show potential for improved clinical thrombolytic therapy.


Assuntos
Portadores de Fármacos , Nanopartículas de Magnetita/química , Estreptoquinase/administração & dosagem , Terapia Trombolítica/métodos , Ativador de Plasminogênio Tecidual/administração & dosagem , Doenças Vasculares/tratamento farmacológico , Química Farmacêutica/métodos , Estabilidade de Medicamentos , Humanos , Concentração de Íons de Hidrogênio , Tamanho da Partícula , Propilaminas/química , Silanos/química , Dióxido de Silício/química , Streptococcus equi/enzimologia , Streptococcus equi/crescimento & desenvolvimento , Estreptoquinase/farmacologia , Propriedades de Superfície , Temperatura , Ativador de Plasminogênio Tecidual/farmacologia
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