近年來螢光感測器應用於對金屬離子的感測越來越受到關注，金屬離子維持人體許多功能的運行，金屬離子在人體中的量過多或過少均會造成危害，因此檢測金屬離子在環境中的含量變得極其重要。相較於其他測定金屬離子的儀器，螢光感測器有許多優點，例如：容易操作、成本低、量測時間短。
本研究合成出含希夫鹼之三氮唑衍生物S1作為金屬離子螢光感測器
， S1因光誘導電子轉移(photo-induced electron transfer, PET)的作用，螢光強度低。於乙醇/水(4:1, v/v)中探討對金屬離子的辨識能力及形成錯合物的機制，鋅離子選擇性地增強螢光強度(λem = 465 nm，53倍)，造成此現象的原因是S1與鋅離子作用使光誘導電子轉移被抑制，進而造成螢光增強。同時螢光光譜產生藍位移，推測是鋅離子與電子給予imine基(-C=N-)氮原子的強作用，提高了激發態與基態間的能量差。由Job plot實驗得到S1與鋅離子形成錯合物的配位比例是1:3，由濃度滴定實驗得到偵測極限(LOD)是1.23 × 10-7 M。另外，S1與鋅離子形成錯合物造成顏色改變可直接以肉眼辨識，以Na2EDTA測試S1之可逆性，發現螢光強度的回復性佳，且S1在pH = 4.2到pH = 11的環境下皆可有效地感測鋅離子。

A Schiff base-containing fluorescent sensor S1 was synthesized by Suzuki coupling reaction. The structure is characterized by 1H NMR and MALDI/TOF-MS. S1 was developed for the detection of Zn2+ ion in EtOH-H2O solution. It exhibited weak fluorescence due to photo-induced electron transfer (PET). However, the strong fluorescent emission can be observed in the prescence of Zn2+ (20 eq) with over 53-fold enhancement at 465 nm. Furthermore, the blue shift in emission are attributed to the coordination of imine nitrogen with Zn2+ which increase the band gap between the excited state and ground state. The stoichiometric ratio between S1 and Zn2+ is 1:3 obtained by Job plot. The limit of optical detection (LOD) is 1.23 × 10-7 M derived from titration experiment. The formation of S1-Zn2+ is chemically reversible and the color change could be directly observed by naked eye. In addition, S1 showed good sensing ability under wide pH value ranging from 4.2 to 11.

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