Photothermal Manipulation of Membranes

Abstract

There is emerging evidence that highly controlled nanoscale heating processes can be used to manipulate biological membrane events such as pore formation, bilayer translocation, and fusion. These processes may have diverse applications in triggered drug release, gene transfection, and hybridoma formation. The goal of this work is to devise new methods of producing nanoscale heating and to exploit this phenomenon as a way to manipulate biomembrane structure and function. Photothermal gold nanoparticles have been explored for these purposes but suffer from size-restricted diffusion limitations and poor clearance profiles, while many photothermal organic dyes are susceptible to photobleaching. Our lab has developed high performance near infrared (NIR) dyes and dye loaded nanoparticles which generate heat upon absorption of NIR laser light, making them ideal for in vivo applications.1,2 These photothermal agents were incorporated into cells and artificial membranes, and heat was produced with precise spatiotemporal control. Membranes sensitive to temperature were shown to release encapsulated contents and to have increased bilayer translocation rates. Recent work with artificial temperature insensitive membranes and cell membranes is also discussed. (1) Spence, G. T.; Hartland, G. V.; Smith, B. D. Chem. Sci.2013, 4, 4240 (2) Spence, G. T.; Lo, S. S.; Ke, C.; Destecroix, H.; Davis, A. P.; Hartland, G. V.; Smith, B. D. Chem. Eur. J.2014, 20, 12628