Spatial and Temporal Control of Stimuli-Responsive Theranostic Nanomaterials Using Caged Functional DNA Molecules
Theranostic nanomaterials have shown potentials for molecular diagnostic tests and targeted therapeutics in modern medicine. To reach their full potentials for clinical applications, novel methods for spatial and temporal control of stimuli-responsive nanomaterials are required in order to elucidate detailed mechanisms of theranostic effects in vivo and to personalize the diagnostics and treatments in clinics. Toward this goal, we have been selecting, from a large DNA library of up to 1015 different sequences, functional DNA molecules, such as DNAzymes (DNA molecules with enzymatic activities) and DNA aptamers (DNA molecules that can bind targets selectively) that can bind a wide variety of targets, especially those small molecular biomarkers that antibodies have not been able to recognize . When conjugated to nanomaterials such as gold nanoparticles, quantum dots, liposomes, iron oxide nanoparticles, upconversion nanoparticles and polymeric organic nanoparticles, these functional DNA molecules allow stimuli-responsive assembly or disassembly of these nanomaterials, resulting in target-dependent changes of not only optical and magnetic signals for diagnostics, but also controlled release of therapeutic drugs . To realize the spatial and temporal control of these stimuli-responsive nanomaterials, we have added a caged group to the functional DNA molecules so that these DNA nanomaterials can be delivered into living cells, zebrafish and other animals until a decaging event at a specific location and a certain time is triggered . Recent progress in this area will be presented.
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