木質素是自然界最豐富的天然有機聚合物之一，造紙業將其加工後的副產物便成了鹼木質素，是一種大量且低價的生質廢棄物，主要用於製造界面活性劑等低價商品。因此，本研究主要目的為以生質素廢棄物鹼木質素為前驅物，合成出具有高商業價值的石墨烯量子點。傳統的石墨烯量子點合成方法有水熱法、微波法及化學切割法為主，其缺點在於高溫、高耗能製程的需求，或是冗長的製程時間以及危險藥劑的添加，因此本研究採用綠色製程的大氣常壓微電漿技術將鹼木質素轉變為貴重的石墨烯量子點，透過合成參數的改變使來調控其放光波長，並探討不同光學性質的石墨烯量子點之材料特性。
汞離子是一種劇毒的重金屬離子，在人體內累積後會引發器官衰竭、精神錯亂或死亡等多種症狀。高半胱胺酸是一種人體內的生物分子，人體內含有過高的高半胱胺酸可能會導致阿爾茨海默病、骨質疏鬆症或心血管疾病。因此，汞離子和高半胱胺酸的檢測對於環境保護和人體健康具有重要意義。因此，本研究使用具有光致發光特性的石墨烯量子點來檢測劇毒汞離子和生物分子高半胱胺酸。透過石墨烯量子點與汞離子之靜電吸引力來其進行檢測，造成石墨烯量子點之發光強度下降。不同放光波長之量子點對於汞離子的感測有不同的結果，其可歸因於量子點表面的含氧官能基含量。此外，由於胺基酸中的硫醇基與汞離子之間的強大吸引力，將汞離子與石墨烯量子點分離使其螢光強度上升，透過量子點螢光強度的減少與上升來檢測汞離子與高半胱胺酸濃度。

Recently, biomass resources have attracted high interest in various applications. Lignin is a dominant aromatic polymer, which constitutes the second most abundant organic polymer in the world. In paper industry, alkali Lignin is produced as a byproduct with low commercial value. Therefore, in this project, alkali lignin was used as a precursor to synthesize highly-valued graphene quantum dot (GQD) with tunable emission from blue to yellow by microplasma treatment. Comparing with those conventional synthesis methods, the microplasma synthesis can provide a green, renewable and rapid method to convert biomass waste into highly-valued GQDs.
Mercury(II) ion (Hg2+) is a toxic heavy metal ion, which may accumulate in human body and cause several symptoms including the failure of organs, insanity or death. Homocysteine (Hcy) is a kind of amino acid. The concentrations of the Hcy in the human body are in elevated level may cause Alzheimer's disease, Osteoporosis or Cardiovascular diseases. Therefore, mercury ions and Hcy detection is significant for protecting environment and human health. Herein, the as-synthesized GQD solution play a role as a sensitive dual probe for detect extreme toxic mercury ions and biomolecule homocysteine. The electrostatic force between negative charge GQDs with abundant oxygen-containing groups with Hg2+ ions enable GQD solution to detect it with the limit of detection(LOD) of 116 nM. Furthermore, the strong affinity between Hcy and Hg2+ ions make the intensity of GQDs recovered, owning to Pearson acid-base concept mechanism. The LOD of Hcy is 113 nM with the linear range from 3 to 15 μM, which has a high potential for normal human body detection.

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