使用兩親性分子探針檢測鋁離子的液晶感測器

A liquid crystal sensor applying an amphiphilic molecular probes for detecting aluminum ions

徐佳葦(Chia-Wei Hsu)

指導教授 ： 陳志欣

淡江大學/理學院/化學學系碩士班/碩士(2021年)

https://doi.org/10.6846/TKU.2021.00084

摘要

過去用於檢測金屬離子的液晶感測器，通常需要將液晶銅網網格浸入含有兩親性分子的水溶液中，以控制液晶排列的方向，這讓液晶感測器在使用前需要進行額外的預先溶液混合，使得液晶感測器不適合進行連續監測。在本論文中，我們合成了N-十二烷基乙烷-1,2-二胺 (NN12C)，它既可以作為界面活性劑，又可以作為液晶感測器的分子探針。NN12C在作為摻雜物摻雜入液晶後，因為其胺基質子化後可以做為親水端，在液晶和水界面處產生作用力，因此其可以誘導液晶呈現垂直排列。當鋁離子與NN12C螯合後，誘導液晶排列的作用力消失，從而導致液晶呈現混亂排列，進而產生圖像由暗到亮的的訊號轉變。我們的結果表明，該探針對鋁離子 (Al3+) 表現出良好的選擇性，最小偵測濃度為10 μM。此策略簡化了液晶感測器的操作過程。

關鍵字

液晶感測器 ； 兩親性分子探針 ； 鋁離子檢測

並列摘要

Conventional liquid crystal (LC)-based sensors for detecting metal ions usually apply a copper grid confined with ligand-doped LCs to immerse into the aqueous solutions containing amphiphilic molecules to control the LC orientation, which makes LC-based sensors require additional pre-mixing procedures such that they are not suitable for continuous monitoring. In this work, we synthesized N-dodecyl-ethane-1,2-diamine (NN12C), which can act as both amphiphilic molecules and molecular probes for the development of LC sensors. At an LC/aqueous interface, two amine groups of NN12C was protonated into a hydrophilic end, such that it can align at the interface to cause the homeotropic orientation of LC. After aluminum ions chelated with NN12C, the original orientation of LC was disrupted and resulted into a dark-to-bright transition of LC images. Our results showed that this probe exhibited good selectivity towards aluminum ion (Al3+) with the limit of detection of 10 μM. This strategy simplifies the operation procedures of LC sensors.

並列關鍵字

liquid crystal sensor ； amphiphilic molecular probe ； aluminum ions detection

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