An electrochemical intraocular drug delivery device

Approaches and Challenges of Engineering Implantable Microelectromechanical Systems (MEMS) Drug Delivery Systems for in Vitro and in Vivo Applications

“…Another approach which has been successfully demonstrated by Evans et al [29] and Li et al [30] is the use of a refillable drug reservoir, thus reducing the need to have an extremely large drug reservoir. The disadvantage is that the refill procedure imposes some risks to the patients, especially if the BioMEMS device is implanted to a fragile and sensitive part of the body such as in the eyes.…”

“…The disadvantage is that the refill procedure imposes some risks to the patients, especially if the BioMEMS device is implanted to a fragile and sensitive part of the body such as in the eyes. For example, Li et al [30] have reported that the refill process requires a needle to be directly inserted into the device which is located at the eye surface, where there is a running risk of accidentally puncturing the surrounding eye tissues. Another issue is that there is no indicator within the BioMEMS reservoirs to inform one that the reservoir is fully filled with drug formulation and the overfilling of the reservoir may result in damaging the device.…”

A Modular Heat-Shrink-Packaged Check Valve With High Pressure Shutoff

“…First, the wafer was treated with A-174 (a silane adhesion promoter) to enhance Parylene C adhesion to the soda lime wafer. A 4 μm layer of Parylene C (Specialty Coating Systems, Inc., Indianapolis, IN) was vapor deposited onto the wafer to prevent the SU-8 from delaminating from the wafer due to mismatch of the thermal coefficients of expansion between soda lime and SU-8 [5]. A 75 μm layer of SU-8 2050 was spin coated (30 s, 2000 rpm) and softbaked for 90 min at 95…”

“…We previously reported a drug delivery system consisting of a refillable silicone drug reservoir, flexible Parylene C cannula, and electrolysis pump [5]. Drug was pumped directly into the eye by electrolysis actuation.…”

A remotely operated drug delivery system with an electrolytic pump and a thermo-responsive valve

“…2 Micro-electro-mechanical systems (MEMS) technology offers the potential to develop implantable drug delivery devices with miniaturized size and effective control. Among the preliminary studies, MEMS fabrication-based electrolytic pumps are receiving considerable interest [3][4][5][6] for delivering a variety of drugs due to their ability of transforming electrical energy directly into mechanical work through swelling, bending, and other deformations. Electrolytic actuation, compared to other actuation mechanisms, usually offers the preponderant advantages of stability, low power consumption, and easy operation.…”