Construction of a Near-IR-Luminescent Rectangular Yb(III) Complex from a Dodecadentate Schiff Base Ligand for the Excitation-Wavelength-Dependent Detection of Aloe Emodin (a Natural Medicinal Ingredient)

Abstract

A near-IR-luminescent octanuclear Yb(III) complex 1 was constructed from a new dodecadentate Schiff base ligand, which is used in the rapid and reliable wavelength-dependent detection of aloe emodin (AE) with high sensitivity even in the presence of other interferences.

Two Octa-Nuclear {Ln8} (Ln = Tb, Dy) Complexes with “4 + 4” Covalent Organic Macrocycles: Structure, Solution Behavior, Luminescence, and Magnetic Properties

“…L 4+4 , a four-sided “embedded” macrocyclic Schiff base ligand, was obtained through the in situ condensation reaction of 2-hydroxy-5-methylisophthalaldehyde and 1,3-diaminopropan-2-ol in the ratio of 4:4 (Figures and S1–S3 and Table ). , Each corner of the quadrilateral was occupied by 2-hydroxy-5-methylisophthalaldehyde, while the four sides were occupied by 1,3-diaminopropan-2-ol. In the process of reacting rare earth metal salts, the macrocyclic ligand removed the hydrogen atoms on the phenol hydroxyl and alcohol hydroxyl to form a L 4+4 anion with eight negative charges.…”

“…Lanthanide complexes have been widely used in molecular luminescence and magnetic materials, owing to their unique optical and magnetic properties, including long luminescence lifetimes, large stoke shifts, sharp emission spectra, and/or significant magnetic anisotropy. − Currently, macrocyclic compounds with high-nuclearity lanthanide centers have attracted considerable attention in their structural features and applications in fluorescence probes and molecule magnetic fields. , For example, Yang and co-workers constructed a Eu 18 nanoring through two types of poly dentate Schiff base ligands and 18 Eu­(III) ions, which with ratio-metric fluorescence response to DPA (dipicolinic acid, a major biomarker of Bacillus anthracis) . Tian and co-workers constructed a Dy 24 double-stranded metallo-triangle, exhibited zero-field single molecule-magnet (SMM) behavior …”