A simple synthetic approach to enhance the thermal luminescence sensitivity of Tb³⁺ complexes with thiacalix[4]arene derivatives through upper-rim bromination

Abstract

The thermal sensitivity enhancement of Tb3+-centered luminescence of dimer complexes with thiacalix[4]arene derivatives was achieved through their upper-rim bromination.

Terbium(III)-thiacalix[4]arene nanosensor for highly sensitive intracellular monitoring of temperature changes within the 303–313 K range

“…Both 1 H NMR spectra of the thiacalix [4]arenes and their elemental analysis data ( Fig. S1 in Supplementary Material) are in good agreement with the previously reported results [39][40][41][42] .…”

“…Figure 1a illustrates the structure of four thiacalix [4]arene ligands TCAn (n = 1-4) applied in the present work. As it has been recently reported 38,39 ligands TCAn (n = 2-4) form terbium complexes in the TEA-basified DMF solutions with the 2:2 stoichiometry derived from the sandwich-like coordination of two Tb 3+ ions between two phenolic/phenolate rims schematically represented in Fig. 1b.…”

“…N,N-Dimethylformamide (DMF) (Acros Organics) was twice distilled over P 2 O 5 . Thiacalixarenes TCA1 40 , TCA2 41 , TCA3 39 and TCA4 42 were synthesized according to published procedures. Both 1 H NMR spectra of the thiacalix [4]arenes and their elemental analysis data ( Fig.…”

“…The documented colloids were revealed as efficient fluorescent contrast agents with good cellular uptake behavior 4 . Moreover, some thiacalix [4]arene derivatives has been recently reported 38,39 as the appropriate ligand environment of Tb 3+ ions to generate the Tb 3+ -centered luminescence exhibiting the temperature responsive behavior in physiological temperature range. In particular, the dimeric 2:2 terbium complexes with the bromo-substituted thiacalix [4] arenes provide a promising basis for design of a temperature-sensitive nanomaterial 39 .…”

“…Moreover, some thiacalix [4]arene derivatives has been recently reported 38,39 as the appropriate ligand environment of Tb 3+ ions to generate the Tb 3+ -centered luminescence exhibiting the temperature responsive behavior in physiological temperature range. In particular, the dimeric 2:2 terbium complexes with the bromo-substituted thiacalix [4] arenes provide a promising basis for design of a temperature-sensitive nanomaterial 39 . This is the reason for focusing on the optimal conditions of an efficient conversion of the complexes from molecular blocks in the organic solutions to the water dispersed hydrophilic nanoparticles.…”