Catalogo Articoli (Spogli Riviste)

OPAC HELP

Titolo:
SWELLING AND DISSOLUTION KINETICS DURING PEPTIDE RELEASE FROM ERODIBLE ANIONIC GEL BEADS
Autore:
LEE PI;
Indirizzi:
UNIV TORONTO,FAC PHARM,19 RUSSELL ST TORONTO M5S 2S2 ON CANADA UNIV TORONTO,DEPT CHEM ENGN & APPL CHEM TORONTO M5S 2S2 ON CANADA
Titolo Testata:
Pharmaceutical research
fascicolo: 7, volume: 10, anno: 1993,
pagine: 980 - 985
SICI:
0724-8741(1993)10:7<980:SADKDP>2.0.ZU;2-B
Fonte:
ISI
Lingua:
ENG
Soggetto:
POLYMERS; MATRIX;
Keywords:
SWELLING AND DISSOLUTION KINETICS; FRONT SYNCHRONIZATION; POLY(METHYL METHACRYLATE-CO-METHACRYLIC ACID); SPHERICAL ERODIBLE BEADS; GROWTH HORMONE RELEASING PEPTIDE RELEASE;
Tipo documento:
Article
Natura:
Periodico
Settore Disciplinare:
Science Citation Index Expanded
Science Citation Index Expanded
Citazioni:
16
Recensione:
Indirizzi per estratti:
Citazione:
P.I. Lee, "SWELLING AND DISSOLUTION KINETICS DURING PEPTIDE RELEASE FROM ERODIBLE ANIONIC GEL BEADS", Pharmaceutical research, 10(7), 1993, pp. 980-985

Abstract

The transient dynamic swelling and dissolution behavior during the release of a growth hormone releasing PePtide, [D-Trp2-D-Phe5]GHRP, fromerodible, non-cross-linked poly(methyl methacrylate-co-methacrylic acid) (PMMA/MAA) beads has been investigated at pH 7.4 as a function of buffer concentration. Although the swelling front penetration shows a ionization-limited behavior similar to that of nonerodible cross-linked PMMA/MAA beads, the normalized diameter of the polymer beads exhibits a brief initial rise followed by an extended linear decline due to establishment of the polymer dissolution process. This is consistent with the general kinetic scheme of dissolution of glassy polymers originally predicted for the slab geometry. In all cases, the initial gel thickness increases as a result of the ionization and swelling of the glassy PMMA/MAA beads. This is followed by an extended period of constant gel thickness due to the onset of polymer dissolution and the synchronization of movement of the swelling and dissolution fronts. The resulting constant gel layer thickness as well as the onset and duration of front synchronization shows an increasing trend with decreasing buffer concentrations. As a result, the corresponding peptide release is slower and the release duration longer at lower buffer concentrations. This is believed to be the first time that a synchronization of swelling and dissolution fronts has been documented for a spherical erodiblesample. Although such synchronization of fronts does not result in a constant rate of peptide release due to the spherical geometry, some non-Fickian release characteristics have been observed.

ASDD Area Sistemi Dipartimentali e Documentali, Università di Bologna, Catalogo delle riviste ed altri periodici
Documento generato il 07/07/20 alle ore 21:50:07