High Quantum Yield Fluorescent Carbon Nanodots for detection of Fe (III) Ions and Electrochemical Study of Quenching Mechanism
High Quantum Yield Fluorescent Carbon Nanodots for detection of Fe (III) Ions and Electrochemical Study of Quenching Mechanism
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DOI：
10.1016/j.talanta.2019.120538
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发表时间：
2020-03-01
期刊：
影响因子：
6.1
通讯作者：
Wei, Jianjun
中科院分区：
文献类型：
--
作者：
Arvapalli, Durga M.;Sheardy, Alex T.;Wei, Jianjun
碳纳米点（CND）具有优异的光致发光（PL）特性、生物相容性、水溶性和易于功能化等优点，在光电子、生物成像和传感等领域具有潜在的应用前景。最近强调CND在金属离子的选择性检测是由于对人类和环境安全的日益关注。本文以乙二胺（E-CND）和尿素（U-CND）为原料，采用微波一步法合成了两种荧光碳纳米点（CND）。在350 nm的激发波长下，E-CND和U-CND的量子产率分别为64%和8.4%，表现出良好的荧光性能。E-CND和U-CND都表现出对不同金属离子中Fe（III）离子的高选择性，通过以剂量依赖性方式的荧光猝灭。在0-2000 μ M的线性响应范围内，观察到E-CND和U-CND的检测限分别为18 nM和30 nM，响应时间短（秒）。CND检测自来水和血清样品中的Fe（III）离子，无加标，回收率与Fe（III）样品的100%相似。细胞内化研究证实了CND的定位和活细胞内Fe（III）离子的光学成像传感。电荷转移荧光猝灭机制，特别是CND和Fe（III）之间，提出并使用循环伏安法检查。的E-CND的整体特性提供了一个潜在的传感平台，在高灵敏度和选择性检测的Fe（III）离子。
Carbon nanodots (CNDs) offer potential applications in photocatalysis, optoelectronics, bio-imaging, and sensing due to their excellent photoluminescence (PL) properties, biocompatibility, aqueous solubility, and easy functionalization. Recent emphasis on CNDs in the selective detection of metal ions is due to the growing concern for human and environmental safety. In this work, two types of fluorescent carbon nanodots (CNDs) are synthesized economically from ethylene diamine (E-CNDs) or urea (U-CNDs) in a single step microwave process. The as-prepared CNDs exhibit excellent PL at an excitation wavelength of 350 nm with a quantum yield of 64% for E-CNDs and 8.4% for U-CNDs with reference to quinine sulfate. Both E-CNDs and U-CNDs demonstrate high selectivity towards Fe (III) ions among different metal ions, by fluorescence quenching in a dose dependent manner. The limit of detection of E-CNDs and U-CNDs is observed to be 18 nM and 30 nM, respectively, in the linear response range of 0-2000 mu M with a short response time (seconds). The CNDs detect Fe (III) ions in tap water and serum sample with no spiking and the recovery was similar to 100% with the Fe (III) samples. Cellular internalization studies confirm the localization of the CNDs and the optical imaging sensing of Fe (III) ions inside living cells. A charge transfer fluorescence quenching mechanism, specifically between the CNDs and Fe (III), is proposed and examined using cyclic voltammetry. The overall characteristics of the E-CNDs provides a potential sensing platform in highly sensitive and selective detection of Fe (III) ions.