reported a luminescent Tb
3+ complex with pendant quinoline-alkylated diaza-18crown-6 (Fig. 8c). The system showed dual-component recognition of concentrations of H
+ and K
+ at four independent pH ranges, especially in the physiological pH
window. In addition, it exhibited pH- and [K
+
]-independent long-lived lanthanide
luminescent lifetimes in aqueous solution.
Recently, Li and coworkers [36] constructed a novel luminescent and self-calibrating sensor for K
+ constructed by Ln
3+ -directed supramolecular self-assembly
through the coordination of Eu
3+ and Tb
3+ with a crown-connected bis-terpyridine
(Fig. 9). The 18-crown-6 moiety could efficiently regulate the lanthanide luminescence behavior through the binding of potassium ions via K
+
-crown cation-π
interaction, resulting that the supramolecular assembly could be used as a potential
luminescent sensor for selective and quantitative detection of K
+ . Moreover, the
results also showed that the K
+ concentration was linearly correlated with the
emission intensity ratio of
5 D 4 !
7 F 5 transition (Tb
3+ ) to
5 D 0 !
7 F 2 transition
(Eu
3+ ) of the Eu
3+ /Tb
3+ assembly and the detection limit was down to 1 μM.
Therefore, this luminescent lanthanide supramolecular assembly could open a window for the construction of novel sensing materials.
5.3.2 Luminescent Lanthanide Assemblies Based on
Pseudorotaxanes/Pseudopolyrotaxanes
The fabrication of mechanically interlocked supramolecular architectures as integral
components of molecular switches, data storage, and sensor is currently an area of
Fig. 9 Schematic illustration of the construction of lanthanide metal complex and its self-calibrating detection of K
+ [36]. (Adapted with permission [36]. Copyright 2018, Royal Society of
Chemistry)
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Y. Zhou et al.
3+ complex with pendant quinoline-alkylated diaza-18crown-6 (Fig. 8c). The system showed dual-component recognition of concentrations of H
+ and K
+ at four independent pH ranges, especially in the physiological pH
window. In addition, it exhibited pH- and [K
+
]-independent long-lived lanthanide
luminescent lifetimes in aqueous solution.
Recently, Li and coworkers [36] constructed a novel luminescent and self-calibrating sensor for K
+ constructed by Ln
3+ -directed supramolecular self-assembly
through the coordination of Eu
3+ and Tb
3+ with a crown-connected bis-terpyridine
(Fig. 9). The 18-crown-6 moiety could efficiently regulate the lanthanide luminescence behavior through the binding of potassium ions via K
+
-crown cation-π
interaction, resulting that the supramolecular assembly could be used as a potential
luminescent sensor for selective and quantitative detection of K
+ . Moreover, the
results also showed that the K
+ concentration was linearly correlated with the
emission intensity ratio of
5 D 4 !
7 F 5 transition (Tb
3+ ) to
5 D 0 !
7 F 2 transition
(Eu
3+ ) of the Eu
3+ /Tb
3+ assembly and the detection limit was down to 1 μM.
Therefore, this luminescent lanthanide supramolecular assembly could open a window for the construction of novel sensing materials.
5.3.2 Luminescent Lanthanide Assemblies Based on
Pseudorotaxanes/Pseudopolyrotaxanes
The fabrication of mechanically interlocked supramolecular architectures as integral
components of molecular switches, data storage, and sensor is currently an area of
Fig. 9 Schematic illustration of the construction of lanthanide metal complex and its self-calibrating detection of K
+ [36]. (Adapted with permission [36]. Copyright 2018, Royal Society of
Chemistry)
118
Y. Zhou et al.