Plasmonic nanovesicles can navigate the bloodstream, and, when hit with a quick pulse of laser light, change shape to release their contents. It can then exit the body, leaving only the desired package.

This on-demand, light-triggered drug release method could transform medicine, especially the treatment of cancer. Clinicians are beginning to test plasmonic nanovesicles on head and neck tumors. They can also help efforts to study the nervous system in real-time and provide insights into how the brain works.

Gold nanoparticle-coated liposomes — spherical sacs enclosing a watery core that can be used to carry drugs or other substances into the tissues —- have been demonstrated as promising agents for light-induced content release. But these nanoparticles need to be able to clear the body through the renal system, which limits the size of the nanoparticles to less than few nanometers.

The team used the discrete dipole approximation (DDA) computation method in order to make predictions of the optical absorption features of the gold-coated liposome systems. DDA allows one to compute the scattering of radiation by particles of arbitrary shape and organization. The method has the advantage of allowing the team to design new complex shapes and structures and to determine quantitatively what their optical absorption features will be.