Adsorption of proline amino acid on the surface of fullerene (C20) and boron nitride cage (B12N12): A comprehensive DFT study

In this study, the performance of fullerene (C20) and boron nitride cage (B12N12) as a sensing material for detection of proline was evaluated by density functional theory. For this purpose, the structures of proline, C20, B12N12 and the derived products from the proline adsorption on the surface of nanostructures were optimized geometrically. Then, IR and Frontier molecular orbital calculations were performed on them. The obtained adsorption energies, enthalpy changes (ΔHad) and Gibbs free energy variations (ΔGad) demonstrate that proline adsorption on the surface of the boron nitride cage is exothermic, spontaneous and experimentally feasible. Whilst, the proline interaction with C20 is endothermic, non-spontaneous and experimentally impossible. The effect of temperature on the adsorption process was also checked out and the results reveal that 298 K is the best temperature for the adsorption procedure. The Calculated specific heat capacity values show that boron nitride cage can be utilized as a sensing material in the construction of thermal biosensors for proline determination. The calculated molecular orbital parameters indicate that B12N12 could be used as a neutral ion carrier and also an electroactive sensing material in the development of potentiometric and conductometric biosensors. All of the calculations were implemented by density functional theory method and B3LYP/6-31G(d) basis set.