A novel full symmetric diarylethene-based ratiometric fluorescent sensor for lysine and the application for a logic circuit

Near-infrared fluorescent probe with large Stokes shift for specific detection of lysine

A new near-infrared (NIR) fluorescent probe CL based on coumarin- dicyanoisophorone was synthesized. Addition of Lys to probe CL solution in DMF/H2O (9:1, v/v) medium resulted in noticeable enhancement in the intensity of the fluorescence emission at 702 nm, accompanying distinct color change from yellow to pink. While addition of other amino acids and biothiols (Gly, Hcy, GSH, Glu, Val, Tyr, Arg, Trp, Lys, His, Leu, Phe, Asp and Met) did not bring about substantial changes in both fluorescence emission and color. The detection limit was calculated to be 0.51 μM. Job's plot test revealed that probe CL and Lys formed a complex of 1:1 stoichiometry. Probe CL showed high stability and could be used to recognize Lys in a wide pH range of 4.0-10.0. The sensing mechanism was proposed and verified by 1H NMR spectral measurement. The dual-modal fluorescence turn-on and colorimetric NIR probe with an extremely large Stokes shift of 280 nm may be utilized for highly specific and practical sensing of Lys.

Regio- and Enantioselective Macrocyclization from Dynamic Imine Formation: Chemo- and Enantioselective Fluorescent Recognition of Lysine

The dynamic covalent chemistry of imines is utilized to conduct a regioselective as well as enantioselective synthesis of an unsymmetric (C1) chiral macrocycle from the reaction of an unsymmetric (C1) chiral dialdehyde, (S)-4, that contains a salicylaldehyde unit and a benzaldehyde unit, with lysine, an unsymmetric (C1) chiral diamine. The enantioselectivity is further enhanced in the presence of Zn2+. Compound (S)-4 in combination with Zn2+ is found to be a highly chemoselective as well as enantioselective fluorescent probe for lysine. It can be used to detect specific enantiomers of this amino acid.

Fluorous Phase-Enhanced Fluorescent Sensitivity for Enantioselective Recognition of Lysine

A novel fluorinated chiral dialdehyde (S,S)-1, prepared from (S,S)- or (R,R)-2,6-bis(1-hydroxyethyl)pyridine and 2-naphthol containing a highly fluorinated alkyl group, is found to show enantioselective and chemoselective fluorescent recognition of lysine in the fluorous phase. We discovered that the fluorous phase greatly enhances the fluorescent sensitivity and selectivity of the probe. Thus, the fluorous phase not only can allow the fluorescence measurement to be conducted away from common organic and aqueous media to minimize undesirable interference but also can provide a unique environment to greatly improve the selective fluorescent response.

A New Pyrroloquinoline-Derivative-Based Fluorescent Probe for the Selective Detection and Cell Imaging of Lysine

In this paper, a new pyrroloquinoline-derivative-based fluorescent probe, PQP-1, was prepared for the selective detection of Lys in living cells and natural mineral water for drinking. PQP-1 exhibited high selectivity, low limit of detection, and a wide pH range. PQP-1 could be successfully applied for imaging Lys in living cells and in natural mineral water for drinking. We expect that PQP-1 will expand the detection reaction mechanism and the practical biological applications of Lys.