新型二價銅離子化學偵測分子的合成及評估

Abstract

這個計畫中所設計新型二價銅離子化學偵測分子，是利用醯胺基能夠有選擇性的與二價 銅離子產生鍵結，達到辨識的效果。二價銅離子與醯胺基鍵結時，會產生脫氫的現象； 若醯胺基連接於芳香族的有機物(aromatic compound)，脫氫的現象會造成吸收波長紅 位移(red shift)。在這個計畫中，醯胺基連接於醌(quinone)及鄰苯二胺(o-phenyldiamine)， 來達到對二價銅離子有辨識的效果。計畫分為三個系列，分別是以醌(quinone)、鄰苯二 胺(o-phenyldiamine)及rhodamine 為主，用以偵測二價銅離子。有關所設計化學偵測分子 的評估，包括金屬離子的選擇性(以UV-Vis 及螢光光譜判定)、二價銅離子的鍵結常數 (binding affinity constants)、pH 對鍵結的影響(pH dependent binding study)。有關二價銅離子 與化學偵測分子所形成錯合物的研究，包括晶體結構解析及EPR 光譜。以rhodamine 為 主的化學偵測分子，主要是以”turn-on”模式，二價銅離子的鍵結會產生螢光，將會進行 細胞測試，來評估所設計分子對細胞中二價銅離子的偵測性質。

In this proposal, we design several Cu(II) chemosensors in which Cu(II) recognition is through amide binding. The NH group in amide is attached to aromatic compounds, such as quinone and o-phenyldiamine. Cu(II) binding causes the deprotonation of NH in amide group and results in a red shift in absorption wavelength. In addition, anion induced deprotonation of the NH group in each chemosensor is also studied. Comparison between Cu(II)-induced and anion-induced deprotonation of the NH group will be explored. Three series of Cu(II) chemosensors based on quinone, o-phenyldiamine and rhodamine are designed for Cu(II) sensing. The detailed studies include metal ion selectivity by UV-Vis and fluorescence spectra, binding affinity constants, pH dependent binding study. The properties of Cu(II) complexes such as crystal structures, EPR spectra, and electrochemistry are also important issues in the studies. Chemosensors based on rhodamine detect Cu(II) ions as a turn-on process in which Cu(II) binding in chemosensors causes fluorescence emission. These chemosensors are going to test their Cu(II) detecting ability in living cells.