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Mercury (II) detection by water-soluble photoluminescent ultra-small carbon dots synthesized from cherry tomatoes


Mercury ions have been considered highly toxic to human health. What would be great is to develop the ionic probes without any toxicities themselves. Here, we report a friendly, highly sensitive mercury (II) ionic probe, water-soluble photoluminescence carbon dots which were synthesized by simply hydrothermal treatment of fresh cherry tomatoes without adding any other reagents. The ultra-small (<1 nm) carbon dots show robust excitation-depended photoluminescence under a wide pH range (4–10) or a strong ionic strength of up to 1 M, and the detection limit of mercury (II) has been determined as low as 18 nM. We envision such water-soluble, biocompatible carbon dots that could be applied to biolabeling, bio-imaging, and biosensing fields.

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This work was supported by Grants from the National Natural Science Foundation of China (Nos. 21171086 and 81160213), and Inner Mongolia Grassland Talent (No. 108-108038), Natural Science Foundation of Inner Mongolia Autonomous Region of China (Nos. 2013MS1121 and 2015MS0806), Inner Mongolia Department of Science and Technology (No. 211-202077), and the Inner Mongolia Agricultural University (Nos. 109-108040, 211-109003, and 211-206038).

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Correspondence to Feng Zhang.

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Wang, P., Zhong, RB., Yuan, M. et al. Mercury (II) detection by water-soluble photoluminescent ultra-small carbon dots synthesized from cherry tomatoes. NUCL SCI TECH 27, 35 (2016).

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  • Carbon dots
  • Photoluminescence
  • Cherry tomato
  • Mercury
  • Detection