Quinoline-Based Fluorescent Probe for Ratiometric Detection of Lysosomal pH

A new pH-responsive fluorescent probe has been reported based on protonation-activable resonance charge transfer. In aqueous solution, probe PQ-Lyso exhibits ratiometric detection of pH changes with a large hypsochromic shift of 76 nm and remarkable changes in the fluorescence intensity ratio (<i>R</i> = <i>F</i>_494 nm/<i>F</i>_570 nm, <i>R</i>/<i>R</i>₀ = 105). Furthermore, PQ-Lyso, which is localized to lysosomes in living cells, can calibrate lysosomal pH using fluorescence ratiometry

DataSheet1_Comparative experiment of steel bar corrosion at concrete construction joints.xlsx

Introduction: Construction joint is common and even inevitable in most of the reinforcement concrete structures. This study was to assess the effect of construction joints on chloride-induced corrosion of reinforcing steel in concrete.Methods: Test parameters included two environmental conditions (salt solution immersion condition and cyclic wet-dry condition), two forms of construction joint (direct wet joint and roughened wet joint) and four types of steel bar (mild steel bar, ferritic stainless-steel bar, austenitic-ferritic stainless-steel bar and epoxy-coated steel bar). The corrosion test of 90 specimens was carried out by electrochemical accelerated corrosion method. The weight loss of each steel bar and steel bar section in specimens was measured. An influence coefficient (k_j) of construction joint on local weigh loss of steel bars was defined.Results: Except for epoxy-coated steel bars, the most severe corrosion of experimental steel bars in concrete specimens all occurred at the joints, while the corrosion in non-joint sections of steel bars was relatively uniform and less. The weight loss rate of specimens has the range of 1.18% to 15.73% with an average value of 6.22%. The average k_j of mild steel bars, S11203 stainless steel bars, and S23043 stainless steel bars are 1.38, 1.92, and 1.97, respectively. The average k_j of specimens in immersion condition and cyclic wet-dry condition are 1.44 and 2.07. The corrosion of epoxy-coated steel bars mainly occurred at the damage locations of epoxy coating, not mainly at the joints.Conclusion: Chloride-induced corrosion of steel bars at construction joints was always more severe than at non-joints, especially in cyclic wet-dry environments, even for stainless-steel bar, but epoxy-coated steel bars were excluded.</p

A Strategy for Highly Selective Detection and Imaging of Hypochlorite Using Selenoxide Elimination

A new strategy for HOCl-specific fluorescent probes has been reported based on a selenoxide elimination reaction. Probes CM1 and CM2 were synthesized as the first fluorescent probes containing an arylseleno moiety for hypochlorite according to this strategy. Both probes displayed excellent properties, including high selectivity and sensitivity, fast response, and pH independency toward hypochlorite in vitro and vivo

Rapid Detection of Hydrogen Peroxide Based on Aggregation Induced Ratiometric Fluorescence Change

In surfactant solution, probe D-BBO can detect H₂O₂ with an enhanced reaction rate (<i>k</i>_obs = 1.83 × 10^–2 s^–1) and a large bathochromic shift of 105 nm. Furthermore, D-BBO displays a highly selective response to H₂O₂ over other reactive oxygen species under identical conditions

Rational Design of a Ratiometric and Targetable Fluorescent Probe for Imaging Lysosomal Zinc Ions

Fluorescent detecting and tracking of zinc ions in living cells has become more and more important because the physiological and pathological functions of zinc are highly associated with the timing and discrete distribution of subcellular zinc ion. For the detection of subcellular zinc concentrations with high spatial and temporal reliability, we report the design, synthesis, properties, and bioimaging evaluation of a fluorescent probe, <b>DQZn4</b>, composed of a quinoline scaffold as the ratiometric signaling unit for Zn²⁺ and a dimethylethylamino group as the targeting anchor for lysosomes. In acidic aqueous solution (pH = 5.2), <b>DQZn4</b> features fluorescence emission maximum at 542 nm due to the resonance charge transfer in 4-alkoxy substituted quinoline. Upon binding Zn²⁺, the probe displays significant fluorescent turn-on and ratiometric detection of Zn²⁺ with blue shift of 47 nm and remarkable fluorescence ratio changes (<i>R</i> = <i>F</i>₄₉₅/<i>F</i>_542 nm, <i>R</i>/<i>R</i>₀ = 5.1). Confocal imaging experiments establish that <b>DQZn4</b> is able to localize to lysosomes and respond to lysosomal zinc changes in living cells by using fluorescence ratiometry

Bipyridyltriazolium Chlorobismuthate with Thermo-/Photochromic and Photoluminescent Switching Behaviors Based on ET and CT^†

Matched with 3,5-bis­(pyridine-2-yl)-1,2,4-triazole (2-bpt), a new electron donor–acceptor-based chlorobismuthate­(III) hybrid, [2-bpt]₂[Bi₂Cl₁₀(H₂O)]·5H₂O was prepared solvothermally and characterized. The title compound (hydrated form) and its dehydrated form exhibit photo- and thermo-induced intermolecular electron transfer (ET), which correspond to dual ET photo/thermochromism for hydrated form, charge transfer thermochromism during dehydration, and simultaneously photoluminescent responses, respectively

Correlations between the relative average developmental ratings (A) and corrected percent survival (B) for <i>S</i>. <i>frugiperda</i> lines during the F₁ generation and their offspring during the F₂ generation.

Larvae were reared on corn tissue expressing Cry1F. Pearson correlation results reported as r and P values.</p

Synthesis and Derivatization of an Isomerized Bithiophene Imide (iBTI) Acceptor with a Controllably Twisted Backbone

A heptagonal isomerized bithiophene imide (iBTI) acceptor has been effectively synthesized on a gram scale. Its series of β-, α′,β-, α,α′-, α,α′,β-, and α,α′,β,β′-substituted derivatives can be obtained by controlling brominated sites. Single-crystal analyses indicate that the torsion angle of the imide backbone depends on the number and rigidity of β-substituted groups. Furthermore, the helical chirality of tetrasubstituted and [7]helicene-like derivatives based on iBTI shows great promise for the construction of chiral semiconductor materials

Distribution of the relative average development rating for seven-day old F₁ larvae of S. <i>frugiperda</i> female lines on corn leaf tissue expressing Cry1F (A) or Cry1A.105 + Cry2Ab (B).

<p>Distribution of the relative average development rating for seven-day old F₁ larvae of S. <i>frugiperda</i> female lines on corn leaf tissue expressing Cry1F (A) or Cry1A.105 + Cry2Ab (B).</p