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Chemical Research in Chinese Universities ›› 2013, Vol. 29 ›› Issue (4): 820-824.doi: 10.1007/s40242-013-2343-0

• Articles • Previous Articles    

Adsorption-desorption of Silica Nanoparticles on Poly(ethylene glycol) Brushes Grafted onto Au Substrate Studied by Quartz Crystal Microbalance

WANG Da-peng1,2, YANG Mu-quan1,2, DONG Zhi-xin1,2, BO Shu-qin1, JI Xiang-ling1   

  1. 1. State Key Laboratory of Polymer Physics and Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun 130022, P. R. China;
    2. Graduate University of Chinese Academy of Sciences, Beijing 100049, P. R. China
  • Received:2012-09-10 Revised:2012-10-26 Online:2013-08-01 Published:2013-07-15
  • Contact: JI Xiang-ling E-mail:xlji@ciac.jl.cn
  • Supported by:

    Supported by the National Natural Science Foundation of China(Nos.50621302, 50921062).

Cited

2

Abstract:

The adsorption-desorption of silica nanoparticles(NPs) on poly(ethylene glycol)(PEG) grafted onto gold(Au) substrate was studied by quartz crystal microbalance with dissipation monitoring(QCM-D) technique. The results of frequency and dissipation show that SiO2 NPs can be adsorbed strongly on PEG-SH brushes at pH of 9.6, and a new dense and rigid construction is formed. Adjusting the pH from 9.6 to 12.3 resulted in the desorption of silica NPs from the PEG brushes because of a significant weakening of the hydrogen bond between the silica NPs and PEG chains. In addition, the viscoelastic properties of the system during the adsorption-desorption process were also analyzed via the relationship between the normalized frequency(Δf/n) and mass. And the corresponding atomic force microscopy(AFM) images also exhibit morphological changes during the above process, consistent with the changes in viscoelasticity.

Key words: Adsorption-desorption, Poly(ethylene glycol), Quartz crystal microbalance(QCM), Silica nanoparticles, Atomic force microscopy(AFM)