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Preparation, Purification, and Characterization of Lanthanide Complexes for Use as Contrast Agents for Magnetic Resonance Imaging
Published on: July 21, 2011
Composition-tuned lanthanide molecular cluster aggregates for solid-state time-gated logic and security materials
Maliha Farooq1, Vince Luong1, Diogo Alves Galico1
1Department of Chemistry, University of Alberta, 11227 Saskatchewan Drive, Edmonton, Alberta T6G 2G2, Canada. diogogalico@ualberta.ca.
Abstract:
Traditional optical anti-counterfeiting tags and molecular computers are severely hindered by replication vulnerability, complex multi-wavelength and varying temperature inputs, and slow, diffusion-limited solution kinetics. We report an active, solid-state anti-counterfeiting material using hourglass-shaped {Ln9} lanthanide molecular cluster-aggregates (MCAs) operating under a single excitation wavelength and temperature. By systematically tuning the stoichiometry of bimetallic {Tb9-xEux} metal cores, we demonstrate a proof-of-concept on how to program internal energy transfer (ET) pathways to dictate digital workflows exclusively within the time domain using MCAs. This deterministic kinetic control enables the design of temporal barcodes and the realization of a versatile suite of logic circuits (YES, NOT, AND, and INHIBIT) driven by non-invasive electronic detection gating. Operating within a rigid crystalline network, these systems, exhibit stability over at least 15 runs. This kinetic programming strategy bridges synthetic coordination chemistry and molecular optoelectronics, establishing compositional design strategies for ET kinetics towards multi-dimensional optical information encryption.
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