Photocracking Silica: Tuning The Plasmonic Photothermal Degradation Of Mesoporous Silica Encapsulating Gold Nanoparticles For Cargo Release

The degradation of bionanomaterials is essential for medical applications of nanoformulations, but most inorganic-based delivery agents do not biodegrade at controllable rates. In this contribution, we describe the controllable plasmonic photocracking of gold@silica nanoparticles by tuning the power and wavelength of the laser irradiation, or by tuning the size of the encapsulated gold cores. Particles were literally broken to pieces or dissolved from the inside out upon laser excitation of the plasmonic cores. The photothermal cracking of silica, probably analogous to thermal fracturing in glass, was then harnessed to release cargo molecules from gold@silica@polycaprolactone nanovectors. This unique and controllable plasmonic photodegradation has implications for nanomedicine, photopatterning, and sensing applications.