本研究合成出四苯基乙烯衍生物之螢光單體(E)-3-hydroxy-4-(2-((4'-(1,2,2-triphenylvinyl)-[1,1'-biphenyl]-4-yl)methylene)hydrazine-1-carbonyl)phenylmethacrylate (TPE-CHYM)，其對於Fe3+具有感測能力，當schiff base上的氮原子與Fe3+作用後，會將電子傳遞到Fe3+而引發光誘導電子轉移(photoinduced electron transfer, PET)的發生，形成螢光ON-OFF的機制，將螢光單體以自由基聚合法合成出一系列不同螢光單體比例之共聚高分子poly(NIPAAm-co-NMA-co-TPE-CHYM) (PNNTPE)，此高分子由三種單體所組成，NIPAAm本身具有溫度敏感性，可以使高分子具備收縮與膨潤的特性，而NMA則具有可交聯性，可以使高分子在感測金屬離子時不溶於待測溶液中，最終將高分子經由靜電紡織的技術(electronspinning technique)製備成固態螢光感測器使用。
PNNTPE高分子對於Fe3+感測具有高度的選擇性，在除了Fe2+與Cu2+環境下保有高的辨識性，並從Job’s plot實驗結果得知PNNTPE與Fe3+離子以1:1的比例形成錯合物，且能夠應用在中性以及偏酸性環境下的檢測。此外從螢光滴定結果可以得知高分子在溶液態、纖維態與薄膜態皆展現出高度線性的關係，且溶液態、纖維態以及薄膜態之平均偵測極限可以達到0.62 μM、0.69 μM、0.90 μM，儘管將PNNTPE製備成固態感測器後，感測能力稍微遜色，但固態感測器具有方便攜帶以及簡易操作等特性，且比傳統高分子薄膜態有更好的感測能力。此外纖維態之高分子可利用添加EDTA移除Fe3+離子恢復螢光強度，因此可作為重複利用之感測器。綜合以上，雖然固態纖維高分子感測能力遜於溶液態高分子，然而其具備方便攜帶操作方便以及可重複使用等優點，故仍具有其應用開發價值。

In this study, a tetraphenylethylene-based fluorescent monomer, TPE-CHYM, was successfully synthesized and demonstrated selective sensing capability toward Fe³⁺ ions. Upon coordination of Fe³⁺ with the nitrogen atom of the Schiff base moiety, electron transfer occurs from the ligand to the metal center, triggering a photoinduced electron transfer (PET) process and resulting in a fluorescence "turn-off" response. This monomer was further copolymerized via free radical polymerization with varying feed ratios to yield a series of copolymers, poly(NIPAAm-co-NMA-co-TPE-CHYM) (PNNTPE). The resulting copolymer consists of three functional monomers: NIPAAm, which imparts temperature-responsive swelling and shrinking behavior; NMA, a crosslinkable unit that enhances the structural integrity and prevents dissolution during sensing; and TPE-CHYM, the fluorescent sensing unit. These copolymers were subsequently processed into solid-state fluorescent sensors using the electrospinning technique.
PNNTPE exhibits high selectivity toward Fe³⁺, retaining strong discrimination even in the presence of competing metal ions, with the exception of Cu²⁺. Furthermore, the sensing performance was effective in both neutral and mildly acidic environments. Although the fluorescence response of the polymer decreased slightly in the solid-state form compared to the solution state, the solid-state sensors offer practical advantages such as portability and ease of handling. Furthermore, the polymer in the form of nanofiber showed superior sensing performance compared to traditional polymer films.
In addition, the sensor exhibits reusability, being capable of restoring its fluorescence signal upon the removal of Fe³⁺ ions using EDTA.

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