Two-Photon and Deep-Red Emission Ratiometric Fluorescent Probe with a Large Emission Shift and Signal Ratios for Sulfur Dioxide: Ultrafast Response and Applications in Living Cells, Brain Tissues, and Zebrafishes

Abstract

Sulfur dioxide (SO) is a dangerous environmental pollutant. Excessive intake of it may cause some respiratory diseases and even lung cancer. The development of effective methods for detection of SO is of great importance for the environment and physiology. Herein, we have designed and synthesized a novel two-photon (TP) and deep-red emission ratiometric fluorescent probe (CP) for detection of SO. Notably, the novel probe CP exhibited ultrafast response to SO in less than 5 s and displayed a great emission shift (195 nm) and a large emission signal ratio variation (enhancement from 0.1347 to 100.14). In addition, the unique probe was successfully employed for imaging SO not only in the mitochondria of living cells but also in brain tissues and zebrafishes.

Highly Sensitive and Selective Sulfite Ion Sensor Based on Biochemically Stable Iodo‐Functionalized Coumarin Fluorophores

“…[30] In view of the fact that a plethora of coumarinbased small molecule fluorophores have been attracting widescale attention as anion-sensitive chemical sensors against the notorious sulfites, for instance, our interest to explore the ionsensing potential of D upon a subtle chemical modification of E constituted our hypothesis overdue the strategy and assessment of the former as a budding chemically effective sensor. [31,32] In synchronize with earlier scientific data, we visualised that in lower amounts, the emission behavior increases linearly with increase in concentration. [33] Further, the selectivity experiment of D towards different kind of competing anions (I-, Br À , Cl À , F À , S 2 O 8 2À , NO 2 À , OH À , S À , SO 3 2À , HSO 3 À , AcO À , CO 3 2À , HCO 3 À , NO ; 1000 μM) and related biological thiols (Cys, Hcy and GSH) were carried out by fluorescence spectroscopy (Figure 4a).…”

“…[40,44,47] However, upon a closer introspection of these previously reported coumarin-based chemosensors, the feasibility of their chemical synthesis is somewhat marred by multiple synthetic steps. [31]…”

Hybrid Rhodamine Fluorophores in the Visible/NIR Region for Biological Imaging

“…Recently, Sekar's group also reported the analogous coumarin–rhodamine dyes 170 (λ em =678 nm) and 171 (λ em =668 nm) that could be utilized as viscosity probes in visible and deep red regions . Lin's group demonstrated a sulfur dioxide‐sensitive coumarin–rhodamine fluorophore 172 (λ em =645 nm) that could act as a ratiometric fluorescent probe with a large emission shift and SNR . In summary, coumarin–rhodamine dyes with two excitation or emission wavelengths, have greatly facilitated the design of ratiometric fluorescent probes, thereby avoiding the deleterious effects that environmental factors (e.g., pH, temperature, and solvent polarity) can have on fluorescence analysis.…”

A novel fluorescent probe for rapid detection of sulfur dioxide in living cells

“…[8] Therefore, there is a double-sided effect of SO 2 in mammals' bodies. [9] In other words, the low concentration of SO 2 is not harmful to cells, whereas the high concentration of SO 2 is toxic to cells. [10] When excessive SO 2 is inhaled by the respiratory passage, it may elevate potential health problems in humans.…”