Current stroke treatments are limited to acute phase management, and there are few clinically available drugs for neuron protection or damage repair due to restrictions imposed by the blood-brain barrier. This project envisions an implantable DDS for precise drug dispensing to areas of the brain affected by stroke, using light-activated liposomes and microfluidic control to improve therapeutic effectiveness and minimize off-target side effects.

Reviewing literature on microfluidic trap-and-release mechanisms, it became evident that deformable particles often tend to slip out of traps. To accurately predict this behavior, the Young's-Laplace equation and energy stored in the liposome membrane have been assessed. Next, microfluidic devices that were able to manipulate the liposomes to the desired trapping locations were designed and produced. The trapping behavior of liposomes has been assessed by increasing the hydrostatic pressure under a fluorescent microscope. The results show that the experimental pressure of 50-250 Pa is lower than the expected theoretical predictions and that there exists a diameter threshold of 17-18 μm for which the liposomes show lysis behavior. Finally, the entire DDS concept has been demonstrated using a network of traps using the path-of-least-resistance approach.