Optical Trapping of Gold-Coated Liposomes

S.J. Leung, M. Romanowski
University of Arizona, US

Keywords: controlled release, plasmon resonance, liposome, optical trapping


We recently introduced a nanocomposite material, plasmon resonant gold-coated liposomes, to address unmet needs in area of controlled delivery. Plasmon resonant nanocapsules are created via the deposition of gold onto the surface of 100 nm diameter thermosensitive liposomes. We have previously shown that gold-coated liposomes have a plasmon resonance peak that is tunable in the near-infrared range and that these structures are consequently capable of light-induced release. The plasmon resonant structure facilitates the rapid release of contents encapsulated within the liposome via a photothermal process when illuminated with laser light of a wavelength corresponding to the resonance band. Here, we demonstrate successful optical trapping of gold-coated liposomes that allows for control of movement of these particles within a biological sample. Furthermore, we have computationally refined an experimental system with the potential for delivery and localized release of an encapsulated agent with high spatial and temporal resolution. Using computational modeling, we demonstrate that gold-coated liposomes can be used with a modified optical trap to independently control the trapping of and content release from gold-coated liposomes. Full development of this technology may enable accurate perturbation of cellular functions in response to released compounds, with applications in signaling pathways and drug discovery.