Site specific interactions of amino acids with (ZnO)₁₂ cluster: Density functional approach

Abstract

The Stability and electronic properties of bio-hybrid molecules are investigated in the framework of the first-principles density functional theory. The site-specific interactions between (ZnO)₁₂ nano-cluster and arginine/aspartic acid are investigated. There are partially ionic and covalent bonds between the interacting atoms, higher binding energy 8.86 eV is observed at –COOH site of arginine, and 7.60 eV at –CN site of aspartic acid during the interaction with a nano-cluster. Higher HOMO-LUMO gap 4.3 eV is found in arginine, and smaller 2.6 eV in a cluster, it becomes zero with –COOH site of arginine, and 0.8 eV at –CN site of aspartic acid during the formation of bio-hybrids, i.e. highly stable amino acids arg/asp-nano-cluster (ZnO)₁₂ bio-hybrids are formed with small forbidden energy-gap. This study will support in the formation of drugs which will improve the response in wound healing, immune functioning in burn injuries, and in the treatment of bone dysfunction.

Highlights

• The binding energy is higher in a bio-hybrid at –COOH site of Arg, and –CN site of Asp.

• HOMO-LUMO gap is higher in a pristine Arg (4.3 eV), smaller in a cluster (2.6 eV), zero gap in a bio-hybrid with –COOH site of Arg, smaller 0.8 eV at –CN site of Asp.

• Higher binding energy is found with the small forbidden energy-gap of bio-hybrid molecules.

• This study will support in the formation of drugs which will improve the response in wound healing, immune functioning in burn injuries, and in the treatment of bone dysfunction.

Communicated by Ramaswamy H. Sarma

Keywords:

• Density functional theory
• SIESTA
• Amino acids
• ZnO cluster
• Binding energy
• DOS

Acknowledgements

Author kindly acknowledges to the support received from the management of Shri Shankaracharya Technical Campus, Prof. Mohan L Verma (SSTC) who provided computing facility in the research lab, and to helpful discussions with Prof. Ravindra Pandey (Michigan Technological University, USA).

Disclosure statement

No potential conflict of interest was reported by the author.