現在的重金屬汙染問題越來越嚴重，尤其是汞這類重金屬，會和有機物反應，形成有毒的化合物，加上食物鏈中的生物累積，造成人類和其他生物的危害，世界上著名的案例為1956年日本水俁市發生的水俁病，也就是所謂汞中毒，而現在常用的檢測方法有原子吸收光譜（Atomic Absorption Spectroscopy, AAS）、原子放射光譜法（Atomic Emission Spectroscopy, AES）、感應耦合電漿質譜法（Inductively Coupled Plasma Mass Spectroscopy, ICP-MS）等方法，這些方法需要昂貴的儀器、專業人員操作、成本高。
本研究是要提供一個方便操作和低成本且無須昂貴儀器的方式檢測汞離子的濃度。適體（Aptamer）是我所使用的材料之一，目前常被用來做為疾病檢測，可因鹼基對不同的排列，而對特定目標物有物理性吸附的動作，這樣的原理亦可以用在重金屬的檢測上。在研究中，氧化石墨烯和適體複合物被作為選擇性檢測汞離子（Hg2+）的螢光檢測平台，螢光能量藉由適體和氧化石墨烯之間的螢光能量共振轉移（FRET）被關閉。當Hg2+離子存在時，由於胸腺嘧啶–Hg2+–胸腺嘧啶（T–Hg2+–T）複合物的形成，使得Hg2+離子被捕獲在髮夾構型的適體之間，進而恢復螢光。研究表明氧化石墨烯適體傳感器對在大範圍0.5 μM〜20 μM的Hg2+離子濃度內具有良好的線性響應（R2 = 0.9812）且擁有良好的選擇性。

Recent attention on the problem of heavy metal pollution harmful to human health is attracting many investigations. In particular, heavy metals such as mercury reacting with organic compounds to form toxic compounds, and bioaccumulation in the food chain are seriously harmful to humans and other organisms. Commonly used detection methods including Atomic Absorption Spectroscopy （AAS）, Atomic Emission Spectroscopy （AES）, and Inductive Coupled Plasma Mass Spectroscopy （ICP-MS）, which require expensive instruments, professional operations, and high costs. The purpose of this study is to provide a simpler, lower cost and convenient way to detecting mercury ion（Hg2+）concentrations without expensive instruments.
In this study, graphene oxide and aptamer complexes were used as identification probes for fluorescence detection platform for selective detection of mercury ions （Hg2+）, and fluorescence turn off by fluorescence energy resonance transfer （FRET） between aptamer and graphene oxide. When Hg2+ ions are present, that been trapped between hairpin-shaped aptamer due to the thymine–Hg2+–thymine （T–Hg2+–T）complex , which further activates fluorescence. As show in study that the graphene oxide based aptasensor has a linear response（R2＝0.9812）and good selectivity over the wide range of Hg2+ ion concentrations from 0.5 μM to 20μM.

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