Release Characteristics of Implantable Cylindrical Polyethylene Matrices
| العنوان: | Release Characteristics of Implantable Cylindrical Polyethylene Matrices |
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| المؤلفون: | D Demirtaş, Ercument Karasulu, Gökhan Ertan, Mesut Arici, Tamer Güneri |
| المصدر: | Journal of Pharmacy and Pharmacology. 49:229-235 |
| بيانات النشر: | Oxford University Press (OUP), 1997. |
| سنة النشر: | 1997 |
| مصطلحات موضوعية: | Drug Implants, Pharmacology, chemistry.chemical_classification, Drug Carriers, Materials science, Calorimetry, Differential Scanning, Stereochemistry, Sodium Salicylate, Diffusion, Pharmaceutical Science, Polymer, Polyethylene, Matrix (mathematics), chemistry.chemical_compound, Differential scanning calorimetry, chemistry, Cylinder, Polyethylenes, Composite material, Drug carrier, Dissolution |
| الوصف: | The geometrical relationship between a hemisphere and a cylinder has been investigated for controlled-release systems. The relationship was tested by comparing dissolution results with results from mathematical calculation based on the principles of diffusion for matrix systems. A procedure has been developed for producing implantable, cylindrical, low-density polyethylene matrices, uncoated or coated with a thin impermeable film and a thick paraffin layer except for a hole on the flat faces of the cylinder. Drug matrices were prepared from a blend of sodium salicylate and polymer compressed in an appropriately designed stainless-steel mould at 150°C. Differential scanning calorimetry revealed that no decomposition product was formed in the matrix. When the surface area and the number of holes is increased, drug release also increases. When density is increased, however, drug release decreases significantly. Zero-order drug release was obtained from high-density covered one-hole and two-hole matrices. The diffusion coefficient was calculated as 0.067 day−1. The study suggested that true zero-order drug release could be obtained by drug diffusion from a hole, rather than from geometric shapes in the matrix systems. In addition, for constant release the diffusion area has to increase by approximately 25 mm2 every day, compared to the area of the previous day, because the diffusion distance increases logarithmically. |
| تدمد: | 2042-7158 0022-3573 |
| URL الوصول: | https://explore.openaire.eu/search/publication?articleId=doi_dedup___::e8815392e5de02e5358f75adee596bf7 https://doi.org/10.1111/j.2042-7158.1997.tb06786.x |
| حقوق: | OPEN |
| رقم الأكسشن: | edsair.doi.dedup.....e8815392e5de02e5358f75adee596bf7 |
| قاعدة البيانات: | OpenAIRE |
| تدمد: | 20427158 00223573 |
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