Application of a europium complex, Eu(AA)3phen (AA=acrylic acid, phen=1,10-phenanthroline) as a spectroscopic probe and cleaving reagent of DNA

A new europium complex, Eu (acac)3Aphen (where Hacac and Aphen stand for acetylacetone and 5-acrylamido-1,10-phenanthroline, respectively), was synthesized and characterized by elemental analysis, IR, UV and photoluminescence (PL) spectra. The ligand Aphen not only serves as an antenna ligand but also offers a functional group for polymer precursor. The room-temperature PL spectra of the europium (III) complex are composed of the typical Eu3+ red emission, assigned to transitions between the first excited state (5D0) and the multiplet (7F04). Compared to Eu (acac)2AA (where HAA is acrylic acid), Eu (acac)3Aphen exhibits greatly enhanced quantum efficiency (i.e., 14.1% vs 28.5%) and longer 5D0 lifetime (260 μs vs 568 μs).

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Monochromatic Red Electroluminescence Based on Copolymer of N-Vinylcarbazole and Eu-Complexed Acrylic Acid

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.476-478.1416 ◽

2012 ◽

Vol 476-478 ◽

pp. 1416-1420 ◽

Cited By ~ 1

Author(s):

Wen Guan Zhang ◽

Hui Pang ◽

Sheng Min Zhao

Keyword(s):

Energy Transfer ◽

Phase Separation ◽

Acrylic Acid ◽

Energy Levels ◽

Europium Complex ◽

Molar Ratio ◽

Light Emitting ◽

Light Emitting Devices ◽

Emission Efficiency ◽

Molecular Orbit

Europium complexes exhibited intense red fluorescence with a narrow spectral bandwidth (5-10 nm). But non-uniform blending or dispersion of complex resulted in phase separation, decomposition and inefficient energy transfer to reduce emission efficiency. The complexes were covalently attached to the main chain of polymers, which improved film quality and solubility. Eu(TTA)2(AA)phen as europium complex monomer (ECM) was prepared by Eu3+ coordinating with 1,10-phenanthroline (phen), acrylic acid (AA) and 2-thenoyltrifluoroacetone (TTA). Fluorescent polymer marked as p1-30 (molar ratio for ECM/N-vinylcarbazole (NVK), 1/30) was synthesized. The emissions of ECM and p1-30 in the films peaked at ca. 610 nm. The fluorescence lifetime of p1-30 in solid was measured to be 384.58 (τ1) and 802.44 μs (τ2). The highest occupied molecular orbit (HOMO) and the lowest unoccupied molecular orbit (LUMO) energy levels were -5.36 and -1.99 eV. The red organic light-emitting devices (OLED) A ITO/PEDOT: PSS/PBD: p1-30/AlQ3/LiF/Al and B ITO/PEDOT: PSS/PBD: p1-30/BCP/AlQ3/LiF/Al were fabricated. Devices A and B mainly emitted at 614 nm with full width at half maximum (FWHM) of 12.6 nm and exhibited luminance of 375 and 136 cd/m2 with Commission International de L’Eclairage (CIE) coordinates of (0.50, 0.42) and (0.63, 0.35). The copolymer p1-30 had good film quality to avoid phase separation. The emission from the carbazole moieties was suppressed, electroluminescent (EL) spectra revealed that efficient intramolecular energy transfer from carbazole unit to europium complex occurred and that emission efficiency was greatly improved. Device B showed monochromatic red emission.

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Soft ionic liquid based resistive memory characteristics in a two terminal discrete polydimethylsiloxane cylindrical microchannel

Journal of Materials Chemistry C ◽

10.1039/d0tc03334k ◽

2020 ◽

Vol 8 (38) ◽

pp. 13368-13374

Author(s):

Muhammad Umair Khan ◽

Gul Hassan ◽

Jinho Bae

Keyword(s):

Ionic Liquid ◽

Acrylic Acid ◽

Sodium Hydroxide ◽

Sodium Salt ◽

Resistive Memory ◽

Cylindrical Microchannel ◽

Memory Characteristics ◽

Poly Acrylic Acid

This paper proposes a novel soft ionic liquid (IL) electrically functional device that displays resistive memory characteristics using poly(acrylic acid) partial sodium salt (PAA-Na+:H2O) solution gel and sodium hydroxide (NaOH) in a thin polydimethylsiloxane (PDMS) cylindrical microchannel.

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The Role of the Initiator System in the Synthesis of Acidic Multifunctional Nanoparticles Designed for Molecular Imprinting of Proteins

Periodica Polytechnica Chemical Engineering ◽

10.3311/ppch.15414 ◽

2020 ◽

Vol 65 (1) ◽

pp. 28-41

Author(s):

Marwa Aly Ahmed ◽

Júlia Erdőssy ◽

Viola Horváth

Keyword(s):

Acrylic Acid ◽

Binding Affinity ◽

Molecular Imprinting ◽

Low Temperatures ◽

Ammonium Persulfate ◽

Sodium Bisulfite ◽

Multifunctional Nanoparticles ◽

High Affinity ◽

Initiator System

Multifunctional nanoparticles have been shown earlier to bind certain proteins with high affinity and the binding affinity could be enhanced by molecular imprinting of the target protein. In this work different initiator systems were used and compared during the synthesis of poly (N-isopropylacrylamide-co-acrylic acid-co-N-tert-butylacrylamide) nanoparticles with respect to their future applicability in molecular imprinting of lysozyme. The decomposition of ammonium persulfate initiator was initiated either thermally at 60 °C or by using redox activators, namely tetramethylethylenediamine or sodium bisulfite at low temperatures. Morphology differences in the resulting nanoparticles have been revealed using scanning electron microscopy and dynamic light scattering. During polymerization the conversion of each monomer was followed in time. Striking differences were demonstrated in the incorporation rate of acrylic acid between the tetramethylethylenediamine catalyzed initiation and the other systems. This led to a completely different nanoparticle microstructure the consequence of which was the distinctly lower lysozyme binding affinity. On the contrary, the use of sodium bisulfite activation resulted in similar nanoparticle structural homogeneity and protein binding affinity as the thermal initiation.

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