The reflection of the texture of swollen polymer matrix on the release of incorporated substance
Pavli, Matej (Avtor), Kristl, Julijana (Avtor), Dolenc, Andrej (Avtor), Zvonar Pobirk, Alenka (Avtor), Vrečer, Franc (Avtor), Kosel, Franc (Avtor), Baumgartner, Saša (Avtor)

URLURL - Predstavitvena datoteka, za dostop obiščite http://www.degruyter.com/view/j/epoly.2009.9.issue-1/epoly.2009.9.1.191/epoly.2009.9.1.191.xml Novo okno

Our aim was to investigate the texture of hydrated biopolymer matrices that are now being considered in the design of pharmaceutical controlled-release dosage forms, in order to determine their influence on the release of an active compound. Prolonged release of pentoxifylline, a highly soluble drug, is needed for once-daily administration to achieve its therapeutic effect. Forthis purpose, pentoxifylline was incorporated in a polymer matrix made of acombination of xanthan and locust bean gum (XLBG), both of which are of biotechnological origin. Different methods were used to investigate the interplay of the XLBG gel structure characteristics in the absence and presence of 200 mM CaCl2 on pentoxifylline release: drug-release studies, determination of swelling, erosion, and visco-elasticity of the gel, as well as its texture analysis and microscopic imaging. From the results obtained, the following conclusions can be drawn: the pentoxifylline release from XLBG matrices in water was prolonged for 24 h whereas from the control lactose formulation was completed within 30 min. The presence of Ca2+ ions in water resulted in faster pentoxifylline release, in spite of less swelling and erosion. However, the rheology, texture analysis and scanning electron microscopy revealed that in the presence of the Ca2+ ions the gel layer of theXLBG was more cohesive and thinner, as the attraction for water molecules was lower due to the condensation of counter-ions on the xanthan carboxylic-moieties, and consequently greater interpolymer interactions. Therefore, relatively larger amounts of free water molecules were available within the XLBG hydrogel in the presence of Ca2+, allowing faster drug dissolution and diffusion. Here, the presence of Ca2+ ions had a completely opposite effect on XLBG gel structure and drug release in comparison with other more investigated matrix polymers like alginate or non-ionic cellulose ethers. A firm matrix structure that is accompanied by low swelling and erosion cannot guarantee a more prolonged drug release.

Jezik:Angleški jezik
Ključne besede:polimeri, ksantan, polimerne matrice, mikroskopija
Vrsta gradiva:Delo ni kategorizirano (r6)
Tipologija:1.01 - Izvirni znanstveni članek
Organizacija:FFA - Fakulteta za farmacijo
Leto izida:2009
Št. strani:15 str.
Številčenje:no. 17
ISSN pri članku:1618-7229
COBISS.SI-ID:2510961 Povezava se odpre v novem oknu
Število ogledov:475
Število prenosov:136
Skupna ocena:(0 glasov)
Vaša ocena:Ocenjevanje je dovoljeno samo prijavljenim uporabnikom.
Objavi na: Bookmark and Share

Gradivo je del revije

Založnik:B. Jung
COBISS.SI-ID:2553882 Novo okno

Podobna dela

Podobna dela v RUL:
Podobna dela v drugih slovenskih zbirkah:


Dodaj komentar

Za komentiranje se morate prijaviti.

Komentarji (0)
0 - 0 / 0
Ni komentarjev!