Frontiers in Chemistry (Oct 2018)

Facile Fluorescence “Turn on” Sensing of Lead Ions in Water via Carbon Nanodots Immobilized in Spherical Polyelectrolyte Brushes

  • Yuchuan Tian,
  • Antonios Kelarakis,
  • Li Li,
  • Fang Zhao,
  • Yunwei Wang,
  • Weihua Wang,
  • Qingsong Yang,
  • Zhishuang Ye,
  • Xuhong Guo,
  • Xuhong Guo

DOI
https://doi.org/10.3389/fchem.2018.00470
Journal volume & issue
Vol. 6

Abstract

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Heavy metal detection has become very important for the protection of water resource. In this work, a novel controllable probe is presented for the sensitive detection of Pb2+ in aqueous solutions. The probe was synthesized via the immobilization of surface functionalized carbon dots (named as CAEA-Hs) into the shell of the spherical polyelectrolyte brushes (SPB). The fluorescence of CAEA-H was firstly “turned off” via electrostatic interaction induced quenching. Based on the aggregation induced emission enhancement (AIEE), the fluorescence of the immobilized CAEA-H could be specifically turned on via the aggregation of the SPB particles. This fluorescence “turn on” sensor could selectively detect Pb2+ among five different metal ions with a relatively wide detecting range (0–1.67 mM) and good linear relationship (R2 = 0.9958). Moreover, the aggregating behavior and nano-structure of CAEA-H loaded SPB have been systematically analyzed via small angle X-ray scattering, turbidity titration, and Zeta-potential measurement. Based on a series of control experiments, we finally gain an insight into the sensing mechanism of this novel sensing probe. This contributed a proof of concept demonstration that sensitive and selective chemical detection can be achieved via a C-dot/SPB synergistic platform.

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