Controlled Pulsatile Drug Release from a Ferrogel by a High-Frequency Magnetic Field

Stimuli-responsive controlled release drug from polymeric devices has been received great attention, as it provides advantages such as better delivery efficiency and site-specific therapy over the conventional routes of drug delivery. By making use of these advantages, a number of studies have been successfully proposed to integrate active drug molecules and host materials, to manipulate drug release desirably. Many previous studies have been reported in response to specific stimuli, such as temperature,1-3 pH,4,5 electric field,6,7 mechan-ical signal,8 and ultrasound.9 A very recent achievement of a protein-containing hydrogel, reported by Ehrick et al.,10 ad-dressed the stimuli-sensitive hydrogel that can be triggered as a result of the conformational change of the embedded calm-odulin protein interacting to bioactive agents. Such a transfer from sensing actuation to mechanical action is novel, but it may