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arXiv · 0707.4346

Effect of Protonation on the electronic properties of DNA base pairs: Applications for molecular electronics

Sairam S. Mallajosyula·Swapan K Pati
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Abstract

Protonation of DNA basepairs is a reversible phenomenon which can be controlled by tuning the pH of the system. Under mild acidic conditions, the hydrogen bonding pattern of the DNA basepairs undergoes a change. We study the effect of protonation on the electronic properties of the DNA basepairs to probe for possible molecular electronics applications. We find that, under mild acidic pH conditions, the A:T basepair shows excellent rectification behaviour which is, however, absent in the G:C basepair. The mechanism of rectification has been discussed using a simple chemical potential model. We also consider the non-canonical A:A basepair and find that it can be used as efficient pH dependent molecular switch. The switching action in A:A basepair is explained in the light of pi-pi interactions which lead to efficient delocalization over the entire basepair.

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Sairam S. Mallajosyula, Swapan K Pati. 2007-07-30. Effect of Protonation on the electronic properties of DNA base pairs: Applications for molecular electronics. https://arxiv.org/abs/0707.4346

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