Abstract
A new delivery device based on a novel, squeezing hydrogel concept, utilizing specific swelling-deswelling characteristics of temperature-, temperature/pH- and pH -sensitive hydrogels is described. These hydrogels have been designed to exhibit controlled swelling-deswelling kinetics, hence, a variety of release profiles may be generated including: delayed, zero-order or on-off release profiles. A temperature sensitive NiPAAm/AAc hydrogel demonstrated a squeezing controlled 'on-off' release profile in response to a temperature change between 35°and 40°C with the 'on' phase at higher temperature. Drug release profiles from a pH/T sensitive NiPAAm/BMA/DEAEMA hydrogel were strongly affected by a pH change at 37°C. The gel demonstrated a minimal delayed release at pH 2.0 and a zero-order release at pH 7.4 controlled by mechanical squeezing mechanism that was determined by the gel deswelling kinetics. A delayed and a zero-order release profiles were also obtained for a pH sensitive cationic hydrogel in response to a pH change from pH 2.0 to 7.4. For all studied systems, it was concluded that a gel composition and an applied stimuli (T, pH, pH/T), determined the gel swelling/deswelling kinetics and the release profiles.
| Original language | English |
|---|---|
| Pages (from-to) | 141-148 |
| Number of pages | 8 |
| Journal | Journal of Controlled Release |
| Volume | 48 |
| Issue number | 2-3 |
| DOIs | |
| Publication status | Published - 1997 Oct 13 |
Bibliographical note
Funding Information:The authors wish to thank Dr. H. Jacobs for helpful discussions. This work was supported by MacroMed Inc., Salt Lake City, Utah.
Keywords
- Controlled oral drug delivery
- Drug delivery device
- Swelling/deswelling kinetics
- Temperature-sensitive hydrogels
- pH-Sensitive hydrogels
ASJC Scopus subject areas
- Pharmaceutical Science