ABSTRACT

A novel spirooxazine, MeOBnSPO, as a fluorescence probe was successfully synthesised and its molecular structure was confirmed by single crystal X-ray crystallographic and spectroscopic analyses. The sensing performance of MeOBnSPO for Cu²⁺ was achieved with a ‘turn-on’ fluorescent detection in acetonitrile. The results demonstrated that MeOBnSPO possessed high selectivity towards Cu²⁺ with a 10-fold enhancement in fluorescence intensity (λ_em = 544 nm) and high sensitivity at the micromolar concentration. The limit of detection was calculated to be 19.1 nM. Evidence for the ring opening reaction and 1:1 stoichiometric complexation of MeOBnSPO to Cu²⁺ was proven by ¹H NMR titration, FT-IR, MS, and Job analyses. Moreover, a drastic change in colour from colourless to bright yellow could provide naked-eye detection for Cu²⁺ with rapid response. The viable test strips of MeOBnSPO were also developed for Cu²⁺ colorimetric detection in mixed acetonitrile – H₂O (50:50 v/v).

摘要

成功合成了一种新型螺恶嗪MeOBnSPO作为荧光探针，并通过单晶X射线晶体学和光谱分析证实了其分子结构。^{MeOBnSPO 对 Cu 2+}的传感性能是通过乙腈中的“开启”荧光检测实现的。结果表明，MeOBnSPO对Cu ²⁺具有高选择性，荧光强度增强10倍（λ _em  = 544 nm），并且在微摩尔浓度下具有高灵敏度。检测限经计算为 19.1 nM。^{MeOBnSPO 与 Cu 2+}的开环反应和 1:1 化学计量络合的证据由¹证明H NMR 滴定、FT-IR、MS 和工作分析。此外，颜色从无色到亮黄色的剧烈变化可以提供快速响应的Cu ²⁺肉眼检测。还开发了可行的 MeOBnSPO 测试条，用于混合乙腈 - H _{2 O (50:50 v/v) 中的 Cu} ²⁺比色检测。