scholarly journals Photoluminescence and electroluminescence characterization of high-performance near-infrared emitters based on 1,5-naphthyridin-4-ol-containing heteroleptic platinum(ii) complexes

2021 ◽  
Author(s):  
Hagos Tesfay Kidanu ◽  
Jian Haur Lee ◽  
Chin-Ti Chen
Keyword(s):  
High Performance ◽  
Near Infrared ◽  
Platinum Complexes ◽  
Infrared Emitters

Four 1,5-naphthyridin-4-ol-containing platinum complexes, AtFOND, AtFNND, PBSOND, and PBSNND, have been synthesized and characterized for their photoluminescence (PL) and electroluminescence (EL) properties.

scholarly journals Silicon Vacancy (SiV-) Nanodiamonds as High Performance Near Infrared Emitters for Live Cell Imaging and Particle Tracking

2021 ◽  
Author(s):  
Weina Liu ◽  
Yan Liu ◽  
Viatcheslav N. Agafonov ◽  
Haoyuan Qi ◽  
Kaloian Koynov ◽  
...  
Keyword(s):  
Live Cell Imaging ◽  
High Performance ◽  
Near Infrared ◽  
Cell Imaging ◽  
Infrared Region ◽  
Living Cells ◽  
Silicon Vacancy ◽  
High Pressure High Temperature ◽  
Infrared Emitters ◽  
Narrow Emission

Using tailored nanodiamonds with negatively charged silicon-vacancy (SiV<sup>-</sup>) color centers we performed a series of intracellular experiments. These nanodiamonds with SiV<sup>-</sup> centers (NDs-SiV<sup>-</sup>) were obtained by high-pressure high-temperature (HPHT) synthesis based on metal catalysts-free hydrocarbon HPHT growth. They were coated by a polypeptide biopolymer allowing efficient cellular uptake. High photostability and narrow emission in the near infrared region allows tracking of functionalized NDs-SiV<sup>-</sup> in living cells. The excellent optical properties render NDs-SiV<sup>- </sup>promising nanoemitters for various bioimaging applications. Furthermore, cellular tracking with detailed time, spatial, and spectral information paves the way to intracellular thermometry based on NDs-SiV<sup>-</sup>.

scholarly journals SERS Characterization of the Indocyanine-Type Dye IR-820 on Gold and Silver Nanoparticles in the Near Infrared

2015 ◽  
Vol 2015 ◽  
pp. 1-9 ◽  
Author(s):  
Tatiana B. V. Neves ◽  
Gustavo F. S. Andrade
Keyword(s):  
Gold Nanoparticles ◽  
Silver Nanoparticles ◽  
Raman Spectrum ◽  
High Performance ◽  
Near Infrared ◽  
Cyanine Dyes ◽  
Metallic Surface ◽  
Gold And Silver Nanoparticles ◽  
Biological Compatibility

The Raman spectrum of the indocyanine-type dye IR-820 has been assigned for both solid and solution. SERS spectra of IR-820 on both silver and gold nanoparticles suspensions excited at 1064 nm were obtained. AgNPs allowed the detection of the dye through SERS down to 0.1 micromoles per liter; for the AuNPs the lowest concentration of the dye detectable was 10 micromoles per liter. Changes in the SERS relative intensities compared to the Raman spectrum in solution are subtle, mostly due to the preresonance effect of the dye. However, a perpendicular orientation relative to the metallic surface was inferred for the dye on both AgNPs and AuNPs. The easily distinguishable SERS spectra of the dye excited at 1064 nm, together with the high biological compatibility of cyanine dyes, are both indicative that IR-820 could be used as a high-performance probe molecule for SERS.

scholarly journals Integration of an Optical Setup for the Characterization of Near-Infrared Detectors Used in Ground and Space-Based Astronomy

2021 ◽  
Vol 6 (1) ◽  
pp. 68
Author(s):  
Jorge Jimenez ◽  
Antoni Grau
Keyword(s):  
High Performance ◽  
Near Infrared ◽  
Focal Plane Arrays ◽  
Cdznte Substrate ◽  
Readout Electronic ◽  
Optical Setup ◽  
The North ◽  
Pixel Pitch ◽  
Monochromatic Illumination

To make Europe competitive in the field of astronomical sensors and detectors, the main goal of this research is to provide the capability to manufacture high performance infrared focal plane arrays (FPA) devoted to scientific and astronomical ground and space telescope missions. This paper presents the main outcome of an international project with the highest standard of quality for this detector. The resulting detector is a sensor with a hybridized MCT (HgCdTe) epilayer on a CdZnTe substrate of 2 k × 2 k pixels and 15 μm of pixel pitch. On this framework, an optical setup has been developed at the IFAE optical laboratory with the capabilities to perform the characterization of a near-infrared (NIR) detector covering the range from 800 to 2500 nm. The optical setup is mainly composed of a power controlled quartz–halogen (QTH) lamp and an astigmatism-corrected Czerny–Turner monochromator with two diffraction gratings covering the detector wavelength range with a minimum resolution of ∼1 nm. A temperature stabilized gold-coated integration sphere provides a uniform and monochromatic illumination, while an InGaAs photodiode located at the north pole of the integration sphere is used to measure the radiant flux toward the detector. The whole setup is fully controlled by a Labview™ application and synchronized with the detector’s readout electronic (ROE).

scholarly journals High Performance Near-Infrared Emitters with Methylated Triphenylamine and Thiadiazolo[3,4-g]quinoxaline-Based Fluorophores

Molecules ◽  
2021 ◽  
Vol 26 (21) ◽  
pp. 6386
Author(s):  
Youming Zhang ◽  
Chengjun Wu ◽  
Minrong Zhu ◽  
Jingsheng Miao
Keyword(s):  
Density Functional Theory ◽  
High Performance ◽  
Density Functional ◽  
Near Infrared ◽  
Spatial Configuration ◽  
Parent Compound ◽  
Quantum Yields ◽  
Functional Theory ◽  
Light Emitting Devices ◽  
Infrared Emitters

Three near-infrared emitters (2TPA-QBT, 2MeTPA-BT and TPA-QBT-MeTPA) were rationally designed and synthesized. Density functional theory (DFT) and time-dependent density functional theory (TDDFT) calculations showed that the introduction of mono- or di-methyl groups between the donors and acceptor could result in the spatial configuration changing greatly for 2MeTPA-QBT and TPA-QBT-MeTPA compared to their parent compound 2TPA-QBT. The emission of TPA-QBT-MeTPA had a more obvious hybridized local and charge transfer feature (HLCT) based on the influence of the steric hindrance of the methyl substituent. Attributed to their different spatial configurations and luminescence mechanisms, different emission wavelengths with photoluminescent quantum yields of 26%, 38% and 34% in toluene, as well as 24%, 27% and 31% in 4,4′-bis(N-carbazolyl)-1,1′-biphenyl (CBP) doped film, were observed for 2TPA-QBT, 2MeTPA-QBT and TPA-QBT-MeTPA, respectively. The constructed organic light-emitting devices (OLEDs) displayed electroluminescence with emission peaks at 728, 693 and 710 nm, with maximum external quantum efficiencies of 1.58%, 1.33% and 3.02% for the 2TPA-QBT, 2MeTPA-QBT and TPA-QBT-MeTPA-doped OLEDs, respectively. This work illustrated the effect of spatial configuration changes on the luminescence properties of donor-acceptor-type organic emitters.

Preparation and Characterization of NH2-Terminal Fibrinogen Bβ Fragments from N-DSK of Human Fibrinogen

1984 ◽  
Vol 51 (01) ◽  
pp. 016-021 ◽  
Author(s):  
S Birken ◽  
G Agosto ◽  
B Lahiri ◽  
R Canfield
Keyword(s):  
High Performance ◽  
Gel Filtration ◽  
Ion Exchange Chromatography ◽  
Exchange Chromatography ◽  
Reverse Phase ◽  
Human Fibrinogen ◽  
Human Volunteers ◽  
Cnbr Cleavage ◽  
Two Peaks

SummaryIn order to investigate the early release of NH2-terminal plasmic fragments from the Bβ chain of fibrinogen, substantial quantities of Bβ 1-42 and Bβ 1-21 are required as immunogens, as radioimmunoassay standards and for infusion into human volunteers to determine the half-lives of these peptides. Towards this end methods that employ selective proteolytic cleavage of these fragments from fibrinogen have been developed. Both the N-DSK fragment, produced by CNBr cleavage of fibrinogen, and Bβ 1-118 were employed as substrates for plasmin with the finding of higher yields from N-DSK. Bβ 1-42 and Bβ 1-21 were purified by gel filtration and ion-exchange chromatography on SP-Sephadex using volatile buffers. When the purified preparation of Bβ 1-42 was chromatographed on reverse-phase high performance liquid chromatography, two peaks of identical amino acid composition were separated, presumably due either to pyroglutamate or to amide differences.

Highly Fluorescent Au25-xAgx Nanoclusters Protected with Poly(ethylene glycol) - and Zwitterion-Modified Thiolate Ligands

2018 ◽  
Author(s):  
Dinesh Mishra ◽  
Sisi Wang ◽  
Zhicheng Jin ◽  
Eric Lochner ◽  
Hedi Mattoussi
Keyword(s):  
Quantum Yield ◽  
Near Infrared ◽  
Small Diameter ◽  
Binding Energies ◽  
Thiolate Ligands ◽  
Nir Emission ◽  
Thiolate Complexes ◽  
Long Lifetime ◽  
Poly Ethylene

<p>We describe the growth and characterization of highly fluorescing, near-infrared-emitting nanoclusters made of bimetallic Au<sub>25-x</sub>Ag<sub>x</sub> cores, prepared using various monothiol-appended hydrophobic and hydrophilic ligands. The reaction uses well-defined triphenylphosphine-protected Au<sub>11</sub> clusters (as precursors), which are reacted with Ag(I)-thiolate complexes. The prepared nanoclusters are small (diameter < 2nm, as characterized by TEM) with emission peak at 760 nm and long lifetime (~12 µs). The quantum yield measured for these materials was 0.3 - 0.4 depending on the ligand. XPS measurements show the presence of both metal atoms in the core, with measured binding energies that agree with reported values for nanocluster materials. The NIR emission combined with high quantum yield, small size and ease of surface functionalization afforded by the coating, make these materials suitable to implement investigations that address fundamental questions and potentially useful for biological sensing and imaging applications.<br></p>

Sign in / Sign up

Export Citation Format

Share Document