Surface crosslinking for delayed release of proxyphylline from PHEMA hydrogels.

摘要: Delayed release systems find applications in chronotherapeutics and colon-specific delivery. They have also been considered suitable carriers for the oral delivery of peptides proteins. In prior work, our research group has reported surface crosslinking as an effective technique to modify drug profiles poly(vinyl alcohol) (PVA) hydrogels, reducing early burst effect particular. Here, we demonstrate feasibility delayed proxyphylline from poly(2-hydroxyethyl methacrylate) (PHEMA) hydrogels via crosslinking. Studies on vitro morphology changes PHEMA during swelling showed that highly crosslinked layers ruptures occurring these were likely responsible release. addition, initial was significantly reduced or even eliminated profile achieve near zero-order by judicious selection two parameters: reagent concentration exposure time used treatment.