An electrochemical intraocular drug delivery device

A microelectromechanical systems (MEMS) drug delivery device is investigated for the treatment of incurable ocular diseases. Unlike conventional ocular drug delivery devices, this MEMS device is capable of being refilled, features electronic control of the drug regimen, and enables targeted intraocular drug delivery. The refillable design permits long-term drug therapy and avoids repetitive surgeries. Electronic control of dosing is achieved by using electrolysis-actuated pumping to deliver pharmaceuticals directly to the intraocular space. A flexible Parylene transscleral cannula allows targeted delivery to tissues in both the anterior and posterior segments of the eye. This electrochemically driven drug delivery device was demonstrated to provide flow rates suitable for ocular drug therapy (pL/min to mu L/min). Both continuous and bolus drug delivery modes were performed to achieve accurate delivery of a target volume of 250 nL. An encapsulation packaging technique was developed for acute surgical studies and preliminary ex vivo drug delivery experiments in porcine eyes were performed. (C) 2007 Elsevier B.V. All rights reserved.