Influence of mercaptopropionic-acid-capped CdTe quantum dots on the human chorionic gonadotropin structure and activity alterations

July 28, 2017

Title

Influence of mercaptopropionic-acid-capped CdTe quantum dots on the human chorionic gonadotropin structure and activity alterations

Author

Minglu Hao, Rutao Liu

Year

2016

Journal

RSC Advances

Abstract

As an emerging nanomaterial, quantum dots (QDs) have received enormous attention for their excellent photophysical properties. However, their biotoxicity restricts the application and development of quantum dots. To evaluate the toxicity of quantum dots at the molecular level, the effects of quantum dots on human chorionic gonadotropin (hCG) were explored using spectroscopic techniques and isothermal titration calorimetry (ITC). It was demonstrated that MPA (mercaptopropionic acid)-CdTe QDs interacted with hCG through hydrogen bonds and van der Waals interactions, causing a decrement in the α-helix of the protein and an unfolding process. The conformational changes of hCG lead to the damage of hydrogen bonding networks and the exposure of tyrosine residues to the surface of hCG, which might be the reason why the hCG fluorescence intensity increased and the bioactivity decreased with the increasing concentration of MPA-CdTe QDs.

Instrument

J-810

Keywords

Circular dichroism, Secondary structure, Nanostructures, Ligand binding, Materials, Biochemistry