PhD, University of Cincinnati, 2021, Engineering and Applied Science: Chemical Engineering

The complex structure of the eye and the blood-ocular barriers have impeded the drug delivery via conventional administration routes. Innovative on-demand drug delivery system targeted to the eye has been considered as a promising strategy and received great attention in recent years. Hence, we investigated drug nanocarriers which can be activated by near infrared (NIR) laser to release the payload in a controlled manner over a long period. We first evaluated gold nanorod (AuNR)-coated perfluorocarbon (PFC) nanodroplets with two different PFC cores, perfluoropentane (C5F12, PF5) and perfluorohexane (C6F14, PF6). These PFC nanodroplets undergo a liquid-to-gas phase-transition and “burst” to release the payload with NIR laser. The size, encapsulation efficiency, number density, and cytotoxicity were similar between PF5 and PF6 nanodroplets. The feasibility of both PF5 and PF6 nanodroplets on suppressing the in vitro angiogenesis was demonstrated. PF6 nanodroplets performed better in long-term stability at physiological conditions but showed lower phase-transition efficiency than PF5. Subsequently, AuNR-coated nanosized liposomes (diameter˜100 nm) were studied with a focus on structure reversibility. Laser-triggered drug release tests demonstrated that these AuNR-liposomes released drug repetitively with multiple irradiation cycles (5sec per cycle, 1.1W) and the released amounts were proportional to cycle numbers. It was also proved that AuNR prominently increased the temperature of lipid bilayers via plasmonic heating effect and facilitated drug-releasing when irradiated by NIR laser. In addition, the number density of liposomes remained the same after laser irradiation. These results implied that the structures of AuNR-liposomes are likely to be reversible after exposure to NIR laser. Next, we fabricated micron-sized (diameter˜1.5 µm) AuNR-liposomes by reverse-phase evaporation method. Similarly, these micron-sized liposomes showed repetitive drug releases wi (open full item for complete abstract)

Committee: Yoonjee Park Ph.D. (Committee Chair); Jonathan Nickels (Committee Member); Winston Kao Ph.D. (Committee Member); Gregory Beaucage Ph.D. (Committee Member) Subjects: Chemical Engineering