鋅離子在人體與生物體的代謝及催化反應中扮演著重要的角色，鋅離子過量或不足均會造成嚴重危害。也因此近年來螢光感測器在金屬離子的感測方面的發展越來越受到關注，與其他測定金屬離子的儀器相比，螢光感測器有著容易操作、成本低、量測時間短等優點。
本研究合成具亞胺結構的苯基咔唑衍生物M1及M2作為金屬離子感測器，因光誘導電子轉移 (photo-induced electron transfer, PET) 作用，M1及M2本身螢光強度低。M1於乙醇/水 (4/1, v/v) 溶劑中；M2於二甲基亞碸/水 (4/1, v/v) 溶劑中，探討對於金屬離子的辨識能力及結合機制，與鋅離子選擇性地增強螢光強度 (λem = 495 nm，M1增強137倍；M2增強20倍)，此現象原因為M1及M2與鋅離子作用使光誘導電子轉移被抑制，造成螢光增強。經Job plot實驗得到M1與Zn2+形成錯合物的配位比例是1:1；M2與Zn2+的配位比為1:2。由濃度滴定實驗得到M1與M2對Zn2+的偵測極限分別是2.28×10-8 M及2.63×10-7 M。M1、M2對於Zn2+的螯合辨識在中性及微鹼環境下效果最為明顯。M1與鋅離子作用放光可透過UV燈照射以肉眼觀察到明顯的顏色變化，因分子結構差異M2在螯合Zn2+後螢光增強效果不如M1明顯，且對醇類溶劑溶解度較低，因此在感測器特性上M1優於M2。

Two novel fluorescent sensors M1 and M2 which contain phenylcarbazole core and terminal imine moieties were synthesized through Suzuki coupling reaction and imine condensation. The structures were characterized by NMR spectroscopy and MALDI/TOF-MS. M1 and M2 exhibit poor fluorescence due to photoinduced electron transfer (PET). Upon the addition of Zn2+, an obvious fluorescence emission enhancement at 495 nm could be observed due to the inhibition of PET. From Job plot, the stoichiometric ratio to Zn2+ were 1:1 and 1:2 for M1 and M2, respectively. The limit of detection (LOD) towards Zn2+ of M1 and M2 were 2.28×10-8 M and 2.63×10-7 M, and the binding constants were 105 M-1 and 6.5×108 M-2, respectively. M1 showed good sensing ability under pH value ranging from 6 to 7.7 and 6.9 to 10 for M2.

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