Surface and interface in drug delivery system - ON-OFF regulation of drug release by the surface structural change of thermo-sensitive hydrogels.

Abstract

Stimuli-sensitive polymers which change their structure and physical properties in response to external signals have promising potential in the design of drug delivery systems. In particular, self-regulating or auto feedback drug release system so called “intelligent drug delivery”; may be achieved by utilizing stimuli-sensitive polymers. Random copolymers and interpenetrating networks consisting acrylamide derivative showed excellent thermosensitivity to achieve pulsatile drug release. Quick response of the gel surface to temperature changes is utilized as an on-off switch for drug release and permeation. The data represent the first experimental results showing an on-off switching phenomena of thermosensitive hydrogels which are applicable for modulated pulsatile-controlled release systems.