Probing the interaction of mutiwalled carbon nanotubes and catalase: mutispectroscopic approach

In this study, the mechanism of the interaction between multiwalled carbon nanotubes (MWCNTs) and catalase was investigated by fluorescence, UV-vis, and circular dichroism (CD) spectroscopy under physiological conditions. The fluorescence quenching mechanism of catalase by MWCNTs was shown to be a static quenching procedure and was a result of the formation of a catalase-MWCNT complex. The secondary structure and conformation of the catalase adsorbed on MWCNTs was determined by CD and UV-vis spectroscopy, and the results indicate that the catalase in this complex is partially unfolded with its lost in α-helical content and obtainment in β-sheet content. Moreover, binding of MWCNTs to catalase inhibited the enzymatic activity, which may trigger some toxic effects and undesirable physiological consequences.