132557-72-3Relevant academic research and scientific papers
Rapid and Selective Labeling of Endogenous Transmembrane Proteins in Living Cells with a Difluorophenyl Ester Affinity-Based Probe
Chan, Hsin-Ju,Lin, Xin-Hui,Fan, Syuan-Yun,Ru Hwu, Jih,Tan, Kui-Thong
, p. 3416 - 3420 (2020)
The long-term stability of affinity-based protein labeling probes is crucial to obtain reproducible protein labeling results. However, highly stable probes generally suffer from low protein labeling efficiency and pose significant challenges when labeling low abundance native proteins in living cells. In this paper, we report that protein labeling probes based on an ortho-difluorophenyl ester reactive module exhibit long-term stability in DMSO stock solution and aqueous buffer, yet they can undergo rapid and selective labeling of native proteins. This novel electrophile can be customized with a wide range of different protein ligands and is particularly well-suited for the labeling and imaging of transmembrane proteins. With this probe design, the identity and relative levels of basal and hypoxia-induced transmembrane carbonic anhydrases were revealed by live cell imaging and in-gel fluorescence analysis. We believe that the extension of this difluorophenyl ester reactive module would allow for the specific labeling of various endogenous membrane proteins, facilitating in-depth studies of their distribution and functions in biological processes.
Accessing Structurally Diverse Near-Infrared Cyanine Dyes for Folate Receptor-Targeted Cancer Cell Staining
K?nig, Sandra G.,Kr?mer, Roland
, p. 9306 - 9312 (2017)
Folate receptor (FR) targeting is one of the most promising strategies for the development of small-molecule-based cancer imaging agents considering that the FR is highly overexpressed on the surface of many cancer cell types. FR-targeted conjugates of near-infrared (NIR) emissive cyanine dyes are in advanced clinical trials for fluorescence-guided surgery and are valuable research tools for optical molecular imaging in animal models. Only a small number of promising conjugates has been evaluated so far. Analysis of structure–performance relations to identify critical factors modulating the performance of targeted conjugates is essential for successful further optimization. This contribution addresses the need for convenient synthetic access to structurally diverse NIR-emissive cyanine dyes for conjugation with folic acid. Structural variations were introduced to readily available cyanine precursors in particular via C?C-coupling reactions including Suzuki and (for the first time with these types of dyes) Sonogashira cross-couplings. Photophysical properties such as absorbance maxima, brightness, and photostability are highly dependent on the molecular structure. Selected modified cyanines were conjugated to folic acid for cancer cell targeting. Several conjugates display a favorable combination of high fluorescence brightness and photostability with high affinity to FR-positive cancer cells, and enable the selective imaging of these cells with low background.
A highly selective optical probe for sensing of Fe3+ based on a water-soluble croconaine
Ye, Shouchen,Zhang, Chen,Mei, Jinfeng,Li, Zhongyu,Xu, Song,Li, Xiazhang,Yao, Chao
, p. 130 - 137 (2017)
A highly selective water-soluble optical probe, 2,5-bis[2,3,3-trimethyl-3H-indole-5-sulfonic acid]-croconaine (TISC) was successfully synthesized. TISC can efficiently recognize Fe3+ with the existence of competing cations (Na+, Mg2+, Al3+, Cr3+, Zn2+, K+, Ca2+, Ba2+, Pb2+, Ni2+, Co2+, Ag+, Cu2+, Cd2+) in deionized water. The binding constant (Ka) of TISC-Fe3+ was calculated to be about 3.071?×?104?M?1. Correspondingly, the chelating mode of TISC-Fe3+ was confirmed by Job's plot, FT-IR and 1H NMR. Moreover, Fe3+ and EDTA could be employed as inputs and the absorbance which was 745?nm as output so that a molecular logic gate could be realized, and the test strips of TISC showed a high selectivity to Fe3+.
Synthesis, photophysical characterization and dye adsorption behavior in unsymmetrical squaraine dyes with varying anchoring groups
Hayase, Shuzi,Pandey, Shyam S.,Pradhan, Anusha,Vats, Ajendra Kumar
, (2020)
Four newly designed unsymmetrical squaraine dyes bearing different functional groups for their anchoring on the surface of mesoporous TiO2 were successfully synthesized aiming towards development of far-red sensitizers for dye-sensitized solar cells (DSSCs). The synthesized dyes were characterized by 1H NMR, fast ion bombardment mass, and subjected to photophysical investigations by electronic absorption/fluorescence emission spectroscopy and cyclic voltammetry. These dyes exhibited excellent solubility in a number of common organic solvents. Adsorption behavior of these dyes on the thin films of mesoporous TiO2 was investigated in detail and results indicated that rate of dye adsorption follows the order ?COOH>-PO3H2>OH > SO3H. At the same time, dye desorption studies demonstrated that stability of adsorbed dyes on the mesoporous TiO2 follows the order -PO3H2>>OH>?COOH > –SO3H. Further, implication of the nature of anchoring groups of dye molecules upon the energy levels of their highest occupied molecular orbital and lowest unoccupied molecular orbital was evaluated by both of the combined theoretical and experimental approaches. In spite of enhanced dye loading, very high binding strength and favorable energetic cascade, SQ-143 bearing Phosphonic acid exhibited hampered photovoltaic performance as compared to that of SQ-138 with carboxylic acid anchoring group. Amongst various sensitizers used for present investigation, SQ-138 exhibited best photovoltaic performance having short-circuit current density, open circuit voltage and fill factor of 12.49 mA/cm2, 0.60 V, and 0.53, respectively, leading to power conversion efficiency of 4.07 % after simulated solar irradiation.
Optimized pH-responsive cyanine fluorochromes for detection of acidic environments
Hilderbrand, Scott A.,Weissleder, Ralph
, p. 2747 - 2749 (2007)
Modulation of pH-responsive cyanine dye pKa values via heteroatom substitution allows for design of fluorescent reporters that are tuned for potential imaging of biologically relevant acidic environments. The Royal Society of Chemistry.
Photochromic property of anionic spiropyran with sulfonate-substituted indoline moiety
Sugahara, Akira,Tanaka, Naru,Okazawa, Atsushi,Matsushita, Nobuyuki,Kojima, Norimichi
, p. 281 - 283 (2014)
For fabricating photoresponsive multifunctional materials, we have developed the potassium salt of a new anionic spiropyran, 1′,3′, 3′-trimethyl-6-nitrospiro[2H-1-benzopyran-2,2′-indoline] -5′-sulfonate (1-), with the sulfonate group present on the indoline moiety and whose crystal structure was revealed by single-crystal X-ray diffraction analysis. The photochromism of 1·K was demonstrated at room temperature in the KBr-diluted state, as well as in solution. The protonated spiropyran 1H shows negative photochromism.
Probing two PESIN-indocyanine-dye-conjugates: Significance of the used fluorophore
Benkert, Vanessa,Cheng, Xia,Hübner, Ralph,Kr?mer, Roland,W?ngler, Bj?rn,W?ngler, Carmen
, p. 1302 - 1309 (2020)
Peptide-dye-conjugates hold a great promise in application for biological and medical imaging of cellular processes and in delineation and characterization of human tumors. In particular, indocyanine dyes are of great interest due to their reported superior properties such as absorption and emission in the near-infrared (NIR) spectral range, favorable Stokes shifts and their well-studied safety profile in humans. In this study, we investigated and describe the influence of indocyanine dyes on different properties of the final peptide-dye-conjugates. As a target peptide, PESIN, a bombesin derivative, was used as a model peptide which addresses GRP receptors overexpressed on different malignancies. Here, we map similarities and differences of the fluorescent conjugates and by this elucidate the influence of the dyes on different properties of the formed conjugates. We performed the dye syntheses, subsequent bioconjugation reactions and in the following investigated the optical properties, water/octanol distribution coefficients and target receptor affinities by in vitro competitive binding studies on PC-3 cells. The obtained results give a handrail to medical and biological researchers planning studies involving indocyanine dye biomolecule conjugates.
Synthesis and in vivo fate of zwitterionic near-infrared fluorophores
Choi, Hak Soo,Nasr, Khaled,Alyabyev, Sergey,Feith, Dina,Lee, Jeong Heon,Kim, Soon Hee,Ashitate, Yoshitomo,Hyun, Hoon,Patonay, Gabor,Strekowski, Lucjan,Henary, Maged,Frangioni, John V.
, p. 6258 - 6263 (2011)
To address two fundamental and unsolved problems in optical imaging (nonspecific uptake of near-infrared fluorophores by normal tissues and organs and incomplete elimination of unbound targeted fluorophores from the body), novel zwitterionic near-infrared fluorophores (e.g., ZW800-1) were synthesized and their performance compared in vivo to conventional molecules (e.g., ICG) as a function of charge, charge distribution, and hydrophobicity (see picture). Copyright
A colorimetric squaraine-based probe and test paper for rapid naked eyes detection of copper ion (II)
Liu, Yang,Wang, Liqiu,Guo, Chenxiao,Hou, Yajuan
, p. 3930 - 3933 (2018)
A colorimetric probe N,N’-bis(2-methoxy-ethyl)-2,3,3-trimethyl-3H-squaraine (MOESQ) with H2O solubility was synthesized to detect Cu2+. MOESQ exhibits good selectivity, high sensitivity and fast UV-Vis response toward Cu2+ over other competing ions in CH3CN. The detection limit of MOESQ for Cu2+ in CH3CN can reach 1.88 × 10?7 molL?1. By adsorbing MOESQ on the chromatography paper, a colorimetric test paper for Cu2+ was prepared, which could detect Cu2+ with the color change from blue to faint yellow even in the limit of detection concentration of 10?6 molL?1.
S - Cis Diene Conformation: A New Bathochromic Shift Strategy for Near-Infrared Fluorescence Switchable Dye and the Imaging Applications
Chen, Hsiang-Jung,Chew, Chee Ying,Chang, En-Hao,Tu, Yu-Wei,Wei, Li-Yu,Wu, Bo-Han,Chen, Chien-Hung,Yang, Ya-Ting,Huang, Su-Chin,Chen, Jen-Kun,Chen, I-Chia,Tan, Kui-Thong
, p. 5224 - 5234 (2018)
In this paper, we present a novel charge-free fluorescence-switchable near-infrared (IR) dye based on merocyanine for target specific imaging. In contrast to the typical bathochromic shift approach by extending π-conjugation, the bathochromic shift of our merocyanine dye to the near-IR region is due to an unusual S-cis diene conformer. This is the first example where a fluorescent dye adopts the stable S-cis conformation. In addition to the novel bathochromic shift mechanism, the dye exhibits fluorescence-switchable properties in response to polarity and viscosity. By incorporating a protein-specific ligand to the dye, the probes (for SNAP-tag and hCAII proteins) exhibited dramatic fluorescence increase (up to 300-fold) upon binding with its target protein. The large fluorescence enhancement, near-IR absorption/emission, and charge-free scaffold enabled no-wash and site-specific imaging of target proteins in living cells and in vivo with minimum background fluorescence. We believe that our unconventional approach for a near-IR dye with the S-cis diene conformation can lead to new strategies for the design of near-IR dyes.
