Quantum-mechanical parameters for the risk assessment of multi-walled carbon-nanotubes: A study using adsorption of probe compounds and its application to biomolecules. (November 2016)

• Record Type: Journal Article
• Authors: Chayawan, ; Vikas,
• Is Part Of: Environmental pollution. Volume 218(2016)
• Page Start: 615
• Page End: 624
• Publication Date: 2016-11
• Subjects: Nanosafety -- Carbon-nanotubes -- Electron-correlation -- DNA bases -- Steroid hormones; Pollution -- Periodicals; Pollution -- Environmental aspects -- Periodicals; Environmental Pollution -- Periodicals; Pollution -- Périodiques; Pollution -- Aspect de l'environnement -- Périodiques; Pollution -- Effets physiologiques -- Périodiques; Pollution; Pollution -- Environmental aspects; Periodicals; Electronic journals; 363.73
• DOI: 10.1016/j.envpol.2016.07.045
• Languages: English
• ISSNs: 0269-7491

Abstract

Abstract: This work forwards new insights into the risk-assessment of multi-walled carbon-nanotubes (MWCNTs) while analysing the role of quantum-mechanical interactions between the electrons in the adsorption of probe compounds and biomolecules by MWCNTs. For this, the quantitative models are developed using quantum-chemical descriptors and their electron-correlation contribution. The major quantum-chemical factors contributing to the adsorption are found to be mean polarizability, electron-correlation energy, and electron-correlation contribution to the absolute electronegativity and LUMO energy. The proposed models, based on only three quantum-chemical factors, are found to be even more robust and predictive than the previously known five or four factors based linear free-energy and solvation-energy relationships. The proposed models are employed to predict the adsorption of biomolecules including steroid hormones and DNA bases. The steroid hormones are predicted to be strongly adsorbed by the MWCNTs, with the order: hydrocortisone > aldosterone > progesterone > ethinyl-oestradiol > testosterone > oestradiol, whereas the DNA bases are found to be relatively less adsorbed but follow the order as: guanine > adenine > thymine > cytosine > uracil. Besides these, the developed electron-correlation based models predict several insecticides, pesticides, herbicides, fungicides, plasticizers and antimicrobial agents in cosmetics, to be strongly adsorbed by the carbon-nanotubes. The present study proposes that the instantaneous inter-electronic interactions may be quite significant in various physico-chemical processes involving MWCNTs, and can be used as a reliable predictor for their risk assessment. Graphical abstract: Highlights: Adsorption of organic contaminants by the MWCNTs is modelled. Predictive models based only on three quantum-mechanical parameters are proposed. "Correlated" motion of electrons is found to significantly affect the adsorption. Steroid hormones are predicted to be strongly adsorbed by the carbon-nanotubes. DNA bases are predicted to be less adsorbed by the MWCNTs. Abstract : The role of "correlated" motion of electrons is revealed in the adsorption of biomolecules by the carbon-nanotubes, which can be used as a reliable predictor for their risk assessment.