Qiu Guanhua, Han Yaoqi, Zhu Xiaoqi, Gong Jiawei, Luo Tao, Zhao Chang, Liu Junjie, Liu Jiyang, Li Xiang
Guangxi Medical University Cancer Hospital, Guangxi Medical University, Nanning, China.
Central Hospital Affiliated to Shandong First Medical University, Jinan, China.
Front Chem. 2021 Apr 30;9:658045. doi: 10.3389/fchem.2021.658045. eCollection 2021.
Sulfide ions (S) that are widely distributed in biological and industrial fields are extremely toxic and pose great harms to both ecological environment and human health. However, fluorescent sensors toward S ions commonly use S-recovered fluorescence of fluorophore that is first quenched mainly by metal ions. Fluorescent probe which enables direct, selective, and sensitive detection of S ion is highly desirable. Herein, we demonstrate one-step preparation of fluorescent ionic liquid-graphene quantum dots (IL-GQDs) nanocomposite, which can act as a fluorescent probe for direct and sensitive detection of S ion. The IL-GQDs nanocomposite is easily synthesized facile molecular fusion of carbon precursor and surface modification of GQDs by IL under hydrothermal condition. The as-prepared IL-GQDs nanocomposite has uniform and ultrasmall size, high crystallinity, and bright green fluorescence (absolute photoluminescence quantum yield of 18.2%). S ions can strongly and selectively quench the fluorescence of IL-GQDs because of the anion exchange ability of IL. With IL-GQDs nanocomposite being fluorescent probe, direct and sensitive detection of S is realized with a linear detection range of 100nM-10μM and 10μM-0.2mM (limit of detection or LOD of 23nM). Detection of S ions in environmental river water is also achieved.
广泛分布于生物和工业领域的硫离子（S）具有极强的毒性，对生态环境和人类健康都造成极大危害。然而，用于检测硫离子的荧光传感器通常利用荧光团的硫恢复荧光，而荧光团最初主要被金属离子淬灭。因此，非常需要能够直接、选择性和灵敏地检测硫离子的荧光探针。在此，我们展示了荧光离子液体-石墨烯量子点（IL-GQDs）纳米复合材料的一步制备方法，该材料可作为直接灵敏检测硫离子的荧光探针。IL-GQDs纳米复合材料通过水热条件下碳前驱体的简便分子融合以及IL对GQDs的表面修饰，易于合成。所制备的IL-GQDs纳米复合材料尺寸均匀且超小，具有高结晶度和亮绿色荧光（绝对光致发光量子产率为18.2%）。由于IL的阴离子交换能力，硫离子能够强烈且选择性地淬灭IL-GQDs的荧光。以IL-GQDs纳米复合材料作为荧光探针，实现了对硫离子的直接灵敏检测，线性检测范围为100 nM - 10 μM和10 μM - 0.2 mM（检测限或LOD为23 nM）。同时也实现了对环境河水中硫离子的检测。
