Supramolecular Nucleic Acid-Based Organosilica Nanoparticles Responsive to Physical and Biological Inputs.

Organosilica nanoparticles that contain responsive organic building blocks as constitutive components of the silica network offer promising opportunities for the development of innovative drug formulations, biomolecule delivery, and diagnostic tools. However, the synthetic challenges required to introduce dynamic and multifunctional building blocks have hindered the realization of biomimicking nanoparticles. In this study, capitalizing on our previous research on responsive nucleic acid-based organosilica nanoparticles, we combine the supramolecular programmability of nucleic acid (NA) interactions with sol-gel chemistry. This approach allows us to create dynamic supramolecular bridging units of nucleic acids in a silica-based scaffold. Two peptide nucleic acid-based monoalkoxysilane derivatives, which self-assemble into a supramolecular bis-alkoxysilane through direct base pairing, were chosen as the noncovalent units inserted into the silica network. In addition, a bridging functional NA aptamer leads to the specific recognition of ATP molecules. In a one-step bottom-up approach, the resulting supramolecular building blocks can be used to prepare responsive organosilica nanoparticles. The supramolecular Watson-Crick-Franklin interactions of the organosilica nanoparticles result in a programmable response to external physical (i.e., temperature) and biological (i.e., DNA and ATP) inputs and thus pave the way for the rational design of multifunctional silica materials with application from drug delivery to theranostics.