Plasmon excitation of supported gold nanoparticles can control molecular release from supramolecular systems

Hybrid mesoporous silica materials containing gold nanoparticles (AuNPs) have been investigated as potential molecular delivery systems. The photophysical properties of AuNPs, particularly their plasmon band transitions, have been used to control the rate of the release of naproxen from the pores of mesoporous silica matrices. Two different approaches were employed to incorporate AuNPs into the silica network: that is, grafting (using 3-aminopropyltriethoxisilane) and direct absorption. In this research, the anti-inflamatory drug naproxen serves as a test molecule, showing how localized plasmon heating could be used to modify diffusion kinetics within mesoporous materials. Beyond naproxen release, the methodology developed could be employed to release other drugs, sensors, or active molecules, not just in medicine, but in many other fields where nanotechnology is leading to many innovative applications. The hybrid materials developed show a new simple system to efficiently control the release of active cargo from mesoporous silica matrices.