Drug release triggered by plasmon-heating in mesoporous nanoparticles toward a new drug delivery system.

Mesoporous materials have been recognized as a promising material for drug delivery systems (DDSs), because of their physical properties. While a control of release rate has been intensively explored, triggering of drug release remains a great challenge. Drug release of mesoporous materials relies on a sustained kinetic mechanism, that is, diffusion of encapsulated drugs throughout the pore channels. For dosage application, however, the delivery of drug molecules needs to be modulated or triggered by stimuli. Furthermore, DDSs carrying toxic anti-tumor drugs are required to be ‘zero-leakage of drug’ before reaching the targeted cells or tissues in order to avoid severe side-effect. Therefore, environmental stimuli are not enough sage in some cases, and ‘external stimuli’ is often ideal for safe dosage. Irradiation of metal nanopartilces (NPs) causes excitation of surface plasmon on metal surface. The decay of plasmon leads to a local heating, known as plasmonheating, which offers spatial and temporal heating. The use of plasmon-heating has been recently proposed as an effective trigger of drug release. This project intends to develop a new form of mesoporous DDSs coated with metal semishell and to use plasmon-heating to trigger drug release the loaded drug molecules throughout the mesoporous pores. Plasmon-heating will provide localized thermal effect on diffusion inside mesoporous matrix. Therefore, paralleled ‘zero-leakage’ and ‘triggering drug release” can be realized.