Abstract: In one embodiment, the present invention relates to fluorescent nucleic acid constructs and methods of using these switchable constructs to rapidly screen for target molecule interactions. More particularly, an RNA/DNA chimera comprising a fluorophore-quencher pair and a nucleic acid construct is disclosed for the rapid screening of interactions between the HIV-1 nucleocapsid protein, NCp7, and a stem-loop region, SL3, of the HIV-1 RNA, or antagonists thereof. The compositions and methods disclosed herein can be used in preferred aspects of the present invention for diagnosing disease states, distinguishing the presence of infectious or toxic agents, drug discovery and design, and molecular electronic applications.

Abstract: Embodiments of the invention relate to a branched or multichain nucleic acid switch adapted to switch from a first conformation to a second conformation upon ligand binding. The switch includes a probe strand, P, which includes the ligand binding domain; a switching framework which includes a cover strand (C), and a tether that holds P and C together and a signaling apparatus. Some embodiments include a toggle strand (T) where now the tether holds P, C, T, and the signaling apparatus together. As the switch changes between the first and second conformations; the signaling apparatus reports the state of the switch. The signaling entity is typically a lumiphore and a quencher located along the switching framework. Nucleic acid switches have applications in real time assays for diverse agents including infectious agents, environmental toxins, and terrorist agents, as well as screening methods for such agents. Further applications are found for nanoelectronics, nanofabrication and nanomachines.

Abstract: Described herein are methods for reducing and achieving the desired release of an agent from a delivery system. The desired release kinetics are achieved by exposing the surface of the delivery system with a fluid for a desired period of time.