Investigating Levodopa Adsorption on the Surface of Graphene and Carbon Nanocone by Density Functional Theory

Document Type : Original Article

Authors

• Mohammad Reza Jalali Sarvestani ¹
• Roya Ahmadi ²

¹ Young Researchers and Elite Club, Yadegar-e-Imam Khomeini (RAH) Shahre-rey Branch, Islamic Azad University, Tehran, Iran

² Department of Chemistry, Yadegar-e-Imam Khomeini (RAH) Shahre-rey Branch, Islamic Azad University, Tehran, Iran

Abstract

In this research, the adsorption of levodopa on the surface of graphene and carbon Nanocone was evaluated by density functional theory. for this purpose, the structures of levodopa, graphene, carbon Nano cone and their complexes were optimized geometrically. The negative values of adsorption energy, adsorption enthalpy changes, Gibbs free energy changes and positive values of thermodynamic constants proved that the adsorption process of levodopa is spontaneously, exothermic, irreversible, and experimentally feasible. The values of adsorption enthalpy changes and specific heat capacity indicated graphene and carbon nanocone can be used in the construction of novel thermal sensors for detection of levodopa. The obtained results from frontier molecular orbital calculations showed the energy gap has reduced significantly after levodopa adsorption on the surface of both adsorbents. Therefore, graphene and carbon Nanocone can be utilized as an electroactive recognition element for fabrication of novel levodopa sensitive electrochemical sensors. The values of chemical hardness and dipole moment substantiate that the reactivity and solubility of levodopa has improved after adsorbing on the surface of graphene and carbon nanocone.

Keywords

• Levodopa
• Graphene
• Carbon nanocone
• Density functional theory
• Adsorption

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