Fiber-optic metal ion sensor based on thin-core fiber modal interferometer with nanocoating self-assembled via hydrogen bonding

Bobo Gu, Ming Jie Yin, Aping Zhang, Jin Wen Qian, Sailing He

Research output: Journal article publicationJournal articleAcademic researchpeer-review

18 Citations (Scopus)


A new fiber-optic metal ion sensor based on a thin-core fiber modal interferometer (TCFMI) is presented. Poly(4-vinylpyridine) (P4VP) and poly(acrylic acid) (PAA) are layer-by-layer deposited on the side surface of the TCFMI via hydrogen bonding for the detection of metal ion in aqueous solutions. Ultraviolet-visible (UV-vis) absorption spectroscopy is employed to monitor the self-assembly process, and the thickness and morphology of the nanocoating are characterized by scanning electron microscopy (SEM). When the sensor is immersed into the aqueous solutions containing metal ions, the refractive index (RI) of the nanocoating is changed because of the association of metal ions with the nanocoating, which was verified by energy dispersive X-ray (EDX). Based on the RI sensing capability of TCFMI, one can detect the concentration of metal ions through the measurement of the dip wavelength of the sensor's transmission spectrum. The experiment results exhibit that the sensor is reusable and with a fast response in a wide metal ion concentration range (10 nM-0.1 M). The limit of detection (LOD) of the sensor is around 9.6 nM experimentally.
Original languageEnglish
Pages (from-to)1174-1179
Number of pages6
JournalSensors and Actuators, B: Chemical
Issue number1
Publication statusPublished - 15 Dec 2011
Externally publishedYes


  • Metal ion sensor
  • Optical fiber modal interferometer
  • Optical fiber sensor
  • Self-assembly via hydrogen bonding

ASJC Scopus subject areas

  • Electronic, Optical and Magnetic Materials
  • Instrumentation
  • Condensed Matter Physics
  • Surfaces, Coatings and Films
  • Metals and Alloys
  • Materials Chemistry
  • Electrical and Electronic Engineering

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