Nano Archive

Hemoprotein Bioconjugates of Gold and Silver Nanoparticles and Gold Nanorods: Structure−Function Correlations

Tom, Renjis T. and Samal, A. K. and Sreeprasad, T. S. and Pradeep, T. (2007) Hemoprotein Bioconjugates of Gold and Silver Nanoparticles and Gold Nanorods: Structure−Function Correlations. Langmuir , 23 (3). pp. 1320-1325.

Full text is not hosted in this archive but may be available via the Official URL, or by requesting a copy from the corresponding author.

Official URL: http://pubs.acs.org/doi/abs/10.1021/la061150b

Abstract

Bioconjugates of the hemoproteins, myoglobin, and hemoglobin have been synthesized by their adsorption on spherical gold and silver nanoparticles and gold nanorods. The adsorption of hemoproteins on the nanoparticle surface was confirmed by their molecular ion signatures in matrix assisted laser desorption ionization mass spectrometry and specific Raman features of the prosthetic heme b units. High-resolution transmission electron microscopy (HRTEM) and UV−visible spectroscopy showed that the particles retain their morphology and show aggregation only in the case of silver. The binding of azide ion to the Fe(III) center of the prosthetic heme b moiety caused a red shift of the Soret band, both in the case of the bioconjugates and in free hemoproteins. This was further confirmed by the characteristic signature at 2050 cm-1 in the Fourier-transform infrared spectra, which corresponds to the asymmetric stretching of the Fe(III) bound azide. The retention of the chemical behavior of the prosthetic heme group after adsorption on the nanoparticle is interesting due to its implications in nanoparticle supported enzyme catalysis. The absence of morphology changes after the reaction of bioconjugates with azide ion observed in HRTEM studies implies the stability of nanoparticles under the reaction conditions. All these studies indicate the retention of protein structure after adsorption on the nanoparticle surface.

Item Type:Article
Subjects:Material Science > Nanochemistry
Divisions:Faculty of Engineering, Science and Mathematics > School of Chemistry
ID Code:4477
Deposited By:JNCASR
Deposited On:02 Apr 2009 10:46
Last Modified:02 Apr 2009 10:46

Repository Staff Only: item control page