Sankaran Thayumanavan

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Nonconjugated dendrimers, which are capable of funneling energy from the periphery to the core followed by a charge-transfer process from the core to the periphery, have been synthesized. The energy and electron donors involve a diarylaminopyrene unit and are incorporated at the periphery of these dendrimers. The energy and electron acceptor is at the core(More)
An amphiphilic nanoassembly was designed to respond to the concurrent presence of a protein and an enzyme. We present herein a system, where in the presence of these two stimuli supramolecular disassembly and molecular release occur. This molecular release arises in the form a fluorescence response that has been shown to be specific. We also show that this(More)
We use monodisperse dendrons that allow control over functional group presentation to investigate the influence of the location of a ligand on protein-induced disassembly and release of encapsulated small molecules. Based on both experiments and molecular dynamics simulations, we demonstrate that ligand location greatly influences release of guest molecules(More)
Tree-like dendrimers with decreasing number of chromophores from periphery to core is an attractive candidate for light-harvesting applications. Numerous dendritic designs with different kinds of light-collecting chromophores at periphery and an energy-sink at the core have been demonstrated with high energy transfer efficiency. These building blocks are(More)
The wavelength dependence of the one-photon absorption-induced photodegradation rate has been measured from the visible to the near IR for a variety of electro-optic chromophore-doped polymers. Systematic behavior is identified. The lifetime of the electro-optic activity is found to increase exponentially over 4-6 orders of magnitude for wavelengths ranging(More)
The nonlinear optical properties of four isomeric dipolar two-photon chromophores are compared. The chromophores consist of a carbazole electron donor coupled to a naphthalimide electron acceptor by a phenylacetylene bridge. By variation of the connectivity of the bridge at the phenyl groups, four compounds with 0, 1, and 2 meta linkages are synthesized.(More)
CONSPECTUS: Supramolecular assemblies formed from spontaneous self-assembly of amphiphilic macromolecules are explored as biomimetic architectures and for applications in areas such as sensing, drug delivery, and diagnostics. Macromolecular assemblies are usually preferred, compared with their simpler small molecule counterparts, due to their low critical(More)
A pair of donor-bridge-acceptor electron-transfer complexes, with a carbazole donor and a naphthalimide acceptor connected by either a para- or meta-conjugated phenylacetylene bridge, are synthesized and studied using time-resolved and steady-state spectroscopy. These experiments show that the charge separation times, which depend on the coupling of the(More)
Stimuli-responsive macromolecular assemblies are of great interest in drug delivery applications, as it holds the promise to keep the drug molecules sequestered under one set of conditions and release them under another. The former set of conditions could represent circulation, while the latter could represent a disease location. Over the past two decades,(More)