Acta Phys. -Chim. Sin. ›› 2011, Vol. 27 ›› Issue (07): 1757-1762.doi: 10.3866/PKU.WHXB20110716

• CATALYSIS AND SURFACE SCIENCE • Previous Articles     Next Articles

In situ Study of Self Assembly of Gold Nanoparticles and Cytochrome c by Polarized Optical Waveguide Spectroscopy

ZHANG Rong-Jun, QI Zhi-Mei, ZHANG Zhe   

  1. State Key Laboratory of Transducer Technology, Institute of Electronics, Chinese Academy of Sciences, Beijing 100190, P. R. China
  • Received:2011-03-25 Revised:2011-05-01 Published:2011-06-28
  • Contact: QI Zhi-Mei E-mail:zhimei-qi@mail.ie.ac.cn
  • Supported by:

    The project was supported by the National Natural Science Foundation of China (60978042, 61078039), National Key Basic Research Program of China (2009CB320300), and BaiRenJiHua Program of Chinese Academy of Sciences.

Abstract:

Time-resolved polarized optical waveguide spectroscopy is a powerful technique for the kinetic study of the adsorption of metal nanoparticles and chromophore molecules. We monitored the self- assembling processes of gold nanoparticles and cytochrome c in situ and in real time using this technique. A localized surface plasmon resonance (LSPR) absorption peak for the adsorbed gold nanoparticles gradually red shifted with an increase in the number of adlayers. Moreover, the red shift of the LSPR peak detected with the transverse magnetic (TM) modes is faster than that with the transverse electric (TE) modes. We found that with the TM modes the adsorption of cytochrome c on the gold-nanoparticle adlayer results in a significant red shift of the LSPR peak and a large increase in the peak intensity. In contrast, no obvious changes in the LSPR peak were detected with the TE modes. An analysis of the experimental data verified that the adsorption kinetic behavior of the gold nanoparticles follows a diffusion- control model and cytochrome c adsorption kinetics follows a Langmuir isotherm model. The kinetic parameters for cytochrome c adsorption including the adsorption and desorption rate constants as well as the adsorption free energy were estimated by best fitting the experimental data to the Langmuir model.

Key words: Time-resolved optical waveguide spectroscopy, Gold nanoparticle, Localized surface plasmon resonance, Cytochrome c, Self assembly

MSC2000: 

  • O647