Light- and Microfluidic-guided Release of Drugs - Light Sensitive Liposomes

Abstract

Each year, stroke claims about 5.5 million lives and leaves around 116 million with lasting disabilities. Current stroke treatments focus on the acute phase, lacking drugs for neuron protection or damage repair due to the blood-brain barrier. This proof-of-concept project presents an implantable drug delivery system (DDS) using microfluidics and light-sensitive liposomes for post-stroke treatment in the affected regions of the brain. This research investigates the synthesis, characterization, and application of giant unilamellar vesicles (GUVs) for potential drug delivery applications. Vesicles synthesized by the gel-assisted swelling method. Dye encapsulation studies identified 5 μM as the optimal concentration, with higher concentrations negatively impacting vesicle formation. Stability assessments showed that PEGylation and cholesterol enrichment improved thermal stability and encapsulation efficiency, with lower temperatures generally enhancing stability. Coating GUVs with gold nanoparticles faced challenges with aggregation, indicating the need for optimized reagent concentrations and reduction processes. Dye release studies demonstrated stable encapsulation up to 39°C, suggesting potential for controlled release via surface plasmon resonance. Pipetting was found to better preserve vesicle integrity in microfluidic platforms compared to syringe introduction. Overall, this thesis provides comprehensive knowledge about the synthesis, lipid formulation optimization, and stability of GUVs, offering practical insights into their handling and application in microfluidic platforms, and laying the groundwork for future innovations in drug delivery systems.