Fei Yulang, Zhang Ou, Sun Kai
Department of Biomedical Research Center, Medical College, Xijing University, Xi'an 710123, Shaanxi Province, China.
The First Affiliated Hospital of Nanyang Medical College, Nanyang 473061, Henan Province, China.
ACS Omega. 2025 May 18;10(21):21250-21261. doi: 10.1021/acsomega.4c10587. eCollection 2025 Jun 3.
Optical detection is a promising method for Cu detection with merits, including short sensing times, low cost, sensitive response, and ease of implementation. In this work, tetraphenylethene and triphenylamine were selected as the structural cores for constructing optical probes for Cu. The tetraphenylethene and triphenylamine groups were bonded to a N-N group, forming a probe structure. Additionally, there were two -OH groups near the N-N group, offering additional recognition sites to improve the sensing selectivity. The discussion covered the geometry, electronic transitions, optophysical properties, and spectroscopic behaviors toward copper-(II). It was concluded that the -OH group improved the sensing selectivity by increasing the affinity between the probe and Cu. The electron donors in these dyes compromised the sensing selectivity but decreased the emission recovery time. The optimal probe (P1) decreased its emission quantum from 7.8 to 0.2% by Cu and then recovered to 7.4% by CO within 529 s, with its emission spectrum well recovered. The emission recovery of P1 was sensitive to temperature, and a high temperature (40 °C) helped P1 emission recovery. The recognition principle was yielding a nonemissive adduct between the probe and Cu with a complexation constant of 6.25 × 10 L/mol. The sensing mechanism toward Cu was revealed as the combination of static and dynamic sensing with Job's plot, lifetime comparison, H NMR, and IR comparison. The other four probes, having no -OH groups, exhibited poor sensing selectivity and lower emission recovery values. Their emission recovery times were shorter than that of P1 due to the steric factor and electronic structure. The practical sensing and imaging performance of P1 was tested.
光学检测是一种很有前景的铜检测方法，具有检测时间短、成本低、响应灵敏、易于实施等优点。在本工作中，选择四苯乙烯和三苯胺作为构建铜光学探针的结构核心。四苯乙烯和三苯胺基团与一个N-N基团相连，形成探针结构。此外，在N-N基团附近有两个-OH基团，提供了额外的识别位点以提高传感选择性。讨论涵盖了其几何结构、电子跃迁、光物理性质以及对铜（II）的光谱行为。得出的结论是，-OH基团通过增加探针与铜之间的亲和力提高了传感选择性。这些染料中的电子供体损害了传感选择性，但缩短了发射恢复时间。最佳探针（P1）被铜使其发射量子从7.8%降至0.2%，然后在529秒内被一氧化碳恢复至7.4%，其发射光谱也得到了很好的恢复。P1的发射恢复对温度敏感，高温（40℃）有助于P1的发射恢复。识别原理是探针与铜之间形成一种无发射的加合物，其络合常数为6.25×10 L/mol。通过Job曲线、寿命比较、1H NMR和IR比较揭示了对铜的传感机制是静态和动态传感的结合。另外四个没有-OH基团的探针表现出较差的传感选择性和较低的发射恢复值。由于空间位阻因素和电子结构，它们的发射恢复时间比P1短。测试了P1的实际传感和成像性能。
