An electric-field responsive microsystem for controllable miniaturised drug delivery applications

A novel MEMS based drug delivery device has been developed, consisting of an array of metallic contacts on silicon and Pyrex glass wafers. The meander structured device creates a uniform electric field which stimulates drug release. An electro-active hydrogel based polymer matrix has also been developed, which responds to an electrical stimulus and shrinks or de-swells on application of an electric field from the fabricated device. Different drug candidates can be encapsulated within the polymer matrix. The de-swelling of the polymer enables the encapsulated drug to be released from the matrix. The gel is able to recover its original size once electric stimulation is ceased. By controlling the applied voltage and its duration, the drug release rate and dose can be precisely controlled. Controlled drug delivery devices may be integrated with sensor technology in combined diagnostic/therapeutic point of care devices. (C) 2012 Elsevier B.V. All rights reserved.