کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
---|---|---|---|---|
9918958 | 1557564 | 2005 | 12 صفحه PDF | دانلود رایگان |
عنوان انگلیسی مقاله ISI
XEDS-mapping for explaining release patterns from single pellets
دانلود مقاله + سفارش ترجمه
دانلود مقاله ISI انگلیسی
رایگان برای ایرانیان
کلمات کلیدی
موضوعات مرتبط
علوم پزشکی و سلامت
داروسازی، سم شناسی و علوم دارویی
علوم دارویی
پیش نمایش صفحه اول مقاله
چکیده انگلیسی
A common way to formulate controlled-release (CR) pharmaceuticals is to coat pellets of active substance with a polymer film, decrease the size of the pellets and distribute them as multiple-unit dosages in capsules. To increase the understanding of the release mechanism, the pellet shape and surface structure of pellets, before and after release in microtitre plates, have been studied by scanning electron microscope and X-ray energy-dispersive spectrometry. By performing these studies we associate release profiles during the first few hours to the microscopic structure. Pellets were divided into three classes (spherical pellets, dumbbell shaped pellets and twin-pellets) according to pellet form. Cases of burst release occurred for all three shape classes due to “open-window-defects” at the surface. Areas of thinner polymer film in the neck-region of dumbbell shaped pellets broaden the range of intermediate release rates for this pellet shape. The surface of twin pellets and dumbbell shaped pellets showed more defects, which increases the release rates in comparison to spherical pellets. All pellets with high release rates revealed ruptures in the polymer film, whereas only small cracks could be traced for pellets with slow release rates. The information gained is necessary for the development of future formulations and mathematical modelling of release patterns. The pharmaceutical used as model was remoxipride coated with a polymer film of ethyl cellulose and 10Â wt.% triethyl citrate.
ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: International Journal of Pharmaceutics - Volume 290, Issues 1â2, 16 February 2005, Pages 109-120
Journal: International Journal of Pharmaceutics - Volume 290, Issues 1â2, 16 February 2005, Pages 109-120
نویسندگان
Pernilla Nevsten, Per Borgquist, Anders Axelsson, L. Reine Wallenberg,