Eur. Phys. J. E (2018) 41: 86
https://doi.org/10.1140/epje/i2018-11696-5

Regular Article

Correlation between polar surface area and bioferroelectricity in DNA and RNA nucleobases

¹ Department of Chemistry, Faculty of Science, University of Malaya, 50603, Kuala Lumpur, Malaysia
² Department of Physics, Centre for Theoretical and Computational Physics, Faculty of Science, University of Malaya, 50603, Kuala Lumpur, Malaysia

^* e-mail: vannajan@um.edu.my
^** e-mail: khchew@um.edu.my

Received: 2 February 2018
Accepted: 28 June 2018
Published online: 18 July 2018

Abstract

We have performed computational molecular modelling to study the polarization switching and hysteresis loop behaviours of DNA and RNA nucleobases using the PM3 semi-empirical quantum mechanical approaches. All the nucleobases: adenine (A), thymine (T), guanine (G), cytosine (C), and uracil (U) were modelled. Our study indicates that all the nucleobases exhibit a zero-field polarization due to the presence of polar atoms or molecules such as amidogen and carbonyl. The shape of polarization P versus an applied electric field E hysteresis loop is square, implying typical ferroelectrics behaviour. The total energy U as a function of an applied electric field E exhibits a butterfly-like loop. The presence of zero-field polarization and ferroelectrics hysteresis loop behaviours in nucleobases may support the hypothesis of the existence of bioferroelectricity in DNA and RNA. We also found an interesting relationship between the minimum electric field required for switching and the ratio of the topological polar surface area (TPSA) to the total surface area (TSA) of a nucleobase. In particular, the of a nucleobase is inversely proportional to the TPSA/TSA ratio. This work may provide useful information for understanding the possible existence of ferroelectricity in biomaterials.