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Bioimaging Applications (bioimaging + application)
Selected AbstractsA Lanthanide-Complex-Based Ratiometric Luminescent Probe Specific for PeroxynitriteCHEMISTRY - A EUROPEAN JOURNAL, Issue 22 2010Cuihong Song Abstract A lanthanide-complex-based ratiometric luminescence probe specific for peroxynitrite (ONOO,), 4,-(2,4-dimethoxyphenyl)-2,2,:6,,2,,-terpyridine-6,6,,-diyl]bis(methylenenitrilo)tetrakis(acetate)-Eu3+/Tb3+ ([Eu3+/Tb3+(DTTA)]), has been designed and synthesized. Both [Eu3+(DTTA)] and [Tb3+(DTTA)] are highly water soluble with large stability constants at ,1020, and strongly luminescent with luminescence quantum yields of 10.0 and 9.9,%, respectively, and long luminescence lifetimes of 1.38 and 0.26,ms, respectively. It was found that the luminescence of [Tb3+(DTTA)] could be quenched by ONOO, rapidly and specifically in aqueous buffers, while that of [Eu3+(DTTA)] did not respond to the addition of ONOO,. Thus, by simply mixing [Eu3+(DTTA)] and [Tb3+(DTTA)] in an aqueous buffer, a ratiometric luminescence probe specific for time-gated luminescence detection of ONOO, was obtained. The performance of [Tb3+(DTTA)] and [Eu3+/Tb3+(DTTA)] as the probes for luminescence imaging detection of ONOO, in living cells was investigated. The results demonstrated the efficacy and advantages of the new ratiometric luminescence probe for highly sensitive luminescence bioimaging application. [source] A Molecular Brush Approach to Enhance Quantum Yield and Suppress Nonspecific Interactions of Conjugated Polyelectrolyte for Targeted Far-Red/Near-Infrared Fluorescence Cell ImagingADVANCED FUNCTIONAL MATERIALS, Issue 17 2010Kan-Yi Pu Abstract A red-fluorescent conjugated polyelectrolyte (CPE, P2) is grafted with dense poly(ethylene glycol) (PEG) chains via click chemistry and subsequently modified with folic acid to form a molecular brush based cellular probe (P4). P4 self-assembles into a core,shell nanostructure in aqueous medium with an average size of 130 nm measured by laser light scattering. As compared to P2, P4 possesses not only a substantially higher quantum yield (11%), but also reduced nonspecific interactions with biomolecules in aqueous medium due to the shielding effect of PEG. In conjunction with its high photostability and low cytotoxicity, utilization of P4 as a far-red/near-infrared cellular probe allows for effective visualization and discrimination of MCF-7 cancer cells from NIH-3T3 normal cells in a high contrast, selective, and nonviral manner. This study thus demonstrates a flexible molecular brush approach to overcome the intrinsic drawbacks of CPEs for advanced bioimaging applications. [source] A Molecular Brush Approach to Enhance Quantum Yield and Suppress Nonspecific Interactions of Conjugated Polyelectrolyte for Targeted Far-Red/Near-Infrared Fluorescence Cell ImagingADVANCED FUNCTIONAL MATERIALS, Issue 17 2010Kan-Yi Pu Abstract A red-fluorescent conjugated polyelectrolyte (CPE, P2) is grafted with dense poly(ethylene glycol) (PEG) chains via click chemistry and subsequently modified with folic acid to form a molecular brush based cellular probe (P4). P4 self-assembles into a core,shell nanostructure in aqueous medium with an average size of 130 nm measured by laser light scattering. As compared to P2, P4 possesses not only a substantially higher quantum yield (11%), but also reduced nonspecific interactions with biomolecules in aqueous medium due to the shielding effect of PEG. In conjunction with its high photostability and low cytotoxicity, utilization of P4 as a far-red/near-infrared cellular probe allows for effective visualization and discrimination of MCF-7 cancer cells from NIH-3T3 normal cells in a high contrast, selective, and nonviral manner. This study thus demonstrates a flexible molecular brush approach to overcome the intrinsic drawbacks of CPEs for advanced bioimaging applications. [source] GdIII -Functionalized Fluorescent Quantum Dots as Multimodal Imaging Probes,ADVANCED MATERIALS, Issue 21 2006H. Yang Multimodal probes of GdIII -functionalized silica-coated CdS:Mn/ZnS quantum dots (see figure) that exhibit yellow fluorescence and strong paramagnetism are reported. High magnetic resonance imaging (MRI) contrast is exhibited by these quantum dots. These properties make for a probe that can operate in multiple modes, which is highly desirable for in,vivo bioimaging applications. [source] | ||||||||||