Size-dependent conductivity dispersion of gold nanoparticle colloids in a microchip: Contactless measurements

M. A H Khalafalla, A. Mesli, H. M. Widattallah, A. Sellai, S. Al-Harthi, Haider A J Al-Lawati, F. O. Suliman

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We performed admittance measurements to investigate the particle size dependence of the conductivity of gold nanoparticle (Diameters: 6-100 nm) colloids in electrophoresis microchip in the frequency range of 0.03-1.00 MHz. The admittance was measured with two electrodes capacitively coupled to the colloid contained in a microchip capillary channel. The imaginary and real components of the admittance showed low-frequency dispersion associated with the polarization of the nanoparticles induced by the AC electric field. This was evident from the linear dependence of the process relaxation time as a function of the square of the radius of the nanoparticle.

Original languageEnglish
Article number2546
JournalJournal of Nanoparticle Research
Issue number8
Publication statusPublished - 2014



  • Conductivity
  • Contactless measurement
  • Gold nanoparticles
  • Microchip
  • Relaxation time

ASJC Scopus subject areas

  • Atomic and Molecular Physics, and Optics
  • Condensed Matter Physics
  • Modelling and Simulation
  • Chemistry(all)
  • Materials Science(all)
  • Bioengineering

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