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Quantum confined materials have been extensively studied for photoluminescent applications. Due to intrinsic limitations of low biocompatibility and challenging modulation, the utilization of conventional inorganic quantum confined photoluminescent materials in bio-imaging and bio-machine interface faces critical restrictions. Here, we present aromatic cyclo-dipeptides that dimerize into quantum dots, which serve as building blocks to further self-assemble into quantum confined supramolecular structures with diverse morphologies and photoluminescence properties. Especially, the emission can be tuned from the visible region to the near-infrared region (420 nm to 820 nm) by modulating the self-assembly process. Moreover, no obvious cytotoxic effect is observed for these nanostructures, and their utilization for in vivo imaging and as phosphors for light-emitting diodes is demonstrated. The data reveal that the morphologies and optical properties of the aromatic cyclo-dipeptide self-assemblies can be tuned, making them potential candidates for supramolecular quantum confined materials providing biocompatible alternatives for broad biomedical and opto-electric applications.

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8 A a c h e n -~e r l i n -~o n n -~~~~-~r a c o w -~e i d e l b e r g - COO-1195COO- -197, 1970.London-Vienna Collaboration, Phys. Letters =B, 160 27~llinois-~enova-~amburg-~ilano-~aclay-~arvard- (1971). Toronto-Wisconsin Collaboration, Phys. Rev. LettersWe present measurements on inelastic electron-proton scattering in the region of the A(1236) resonance for two values of q2. A fit to the single-arm and the no-ele~tro~roduction c r o s s sections gave a separation of the resonance and the nonresonant background contribution. The transition form factor G,$(q2) was determined and shown to have a different dependence on q2 than the magnetic nucleon form factor, confirming e a r l i e r measurements. A fit to the angular dependence of the no-electroproduction c r o s s section gives some indications that smaller multipole amplitudes contribute to the resonance besides the dominating M i + amplitude.-

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