Mesoporous silicas are robust silicon dioxide based powders or membranes featuring a periodic arrangement of nanometer-sized channels. Molecules with specific functions can be introduced into the channels, generating materials with potential applications in various fields, including catalysis, sensing, adsorption, and drug delivery. We are primarily developing methods to control and analyze the distribution of molecules on the external particle surface and in the channels of mesoporous silicas. As an extension of this approach, we are investigating the synthesis of molecular pockets. These so-called nanopockets are bound to the channel walls of a mesoporous material and are able to provide a defined environment for guest species. The concept of surface-bound nanopockets offers possibilities for tuning the photophysical properties, catalytic activity, or chemical reactivity of guest molecules, while benefiting from the advantage of a non-toxic silica framework.
The selective binding of molecules to the external particle surface and the channel walls of mesoporous silicas is a prerequisite for developing advanced drug delivery devices. Functional groups on the external surface are responsible for ensuring blood stability and providing targeting ability, whereas the modified channel walls supply sites for drug adsorption and moieties for triggering and controlling the release process.
We further intend to develop novel optical sensors and luminescent markers based on our techniques for selective functionalization and pocket formation. Using a specific technology for a variety of applications allows for achieving multifunctionality through combination. One could, for example, envisage a system capable of delivering drugs to a target while simultaneously acting as a luminescent marker or optical sensor, being able to provide information about the actual site of drug release.