| Author/Editor | Vrečer, Franc; Kramar, Andrejka | |
| Title | Study of the influence of hydrophilic cellulose ethers on pentoxifylline release from sustained-release matrix tablets | |
| Translated title | Študij vpliva hidrofilnih celuloznih etrov na sproščanje pentoksifilina iz ogrodnih tablet z zadržanim sproščanjem | |
| Type | članek | |
| Source | Farm Vestn | |
| Vol. and No. | Letnik 49, št. 3 | |
| Publication year | 1998 | |
| Volume | str. 249-57 | |
| Language | eng | |
| Abstract | The effects of substitution and polymerization degree of cellulose ethers on the pentoxyfilline release profile from sustained-release matrix tablets have been investigated. The results have shown that release profile of pentoxyfilline was mainly influenced by the type of hydroxyalkyl substitution in the cellulose ehter molecules. Contrary to our expectations the influence of hydroxypropylmethyl cellulose molecular weight (polymerization degree) is not specific - in the case of Methocel, it is clearly present; while in the case of Metolose, it was not seen. No sustained-release effect was obtained after incorporating hydroxyethylmethyl cellulose or methyl cellulose into the matrix. Fine tuning of model drug release profile was obtained by combining slow swelling celllulose ethers with both fast ones. Higuchi kinetics of release were found in all studied matrix tablets except those which based on hydroxyethylmethyl cellulose, methyl cellulose or lactose. | |
| Summary | Raziskovali smo vpliv substitucijske in polimerizacijske stopnje celuloznih etrov na profil sproščanja pentoksifilina iz ogrodnih tablet z zadržanim sproščanjem. Rezultati študije so pokazali, da na profil (kinetiko) sproščanja najbolj vpliva tip hidroksialkilne substitucijeceluloznih etrov. V nasprotju s pričakovanji smo ugotovili, da vpliv molske mase (stopnje polimerizacije) hidroksipropilmetil celuloze ni specifičen - v primeru Methocela je jasno prepoznaven, medtem ko v primeru Metolose ni opazen. Z vgradnjo hidroksieltilmetil celuloze oz. metil celuloze v ogrodne tablete nismo dosegli zadržanega sproščanja učinkovine. V kombinaciji s počasi nabrekajočimi celuloznimi etri pa smo po drugi strani z obema hitro nabrekajočima etroma dosegli fino prilagoditev profila sproščanja modelne učinkovine. V večini primerov, razen pri ogrodnih tabletah z vgrajeno hidroksielitilmetil celulozo, metil celulozo oz. laktozo, smo sproščanje pentoksifilina opisali s Higuchijevo kinetiko sproščanja. | |
| Descriptors | DRUG DELIVERY SYSTEMS PENTOXIFYLLINE TABLETS CELLULOSE |