Histamine Adsorption on Pristine and Doped Graphene for Biosensing: A First-Principles Study.

Histamine is a key immune regulator involved in allergic and inflammatory responses and is implicated in a range of immune dysregulation disorders. Reliable, continuous detection of histamine remains challenging due to its low concentrations and dynamic levels of release. In this investigation, the interaction of histamine with pristine and doped graphene monolayers, including oxygen-, boron nitride-, and silicon-doped graphene, was examined as a basis for potential biosensor materials. Density functional theory (DFT) calculations were performed to evaluate adsorption energies, defect formation energies, charge transfer, band structures, and recovery times. The results reveal that pristine graphene exhibits a weak interaction with histamine and a negligible electronic response. Silicon-doped graphene shows high sensitivity but exhibits excessively long recovery times. In contrast, graphene oxide with an oxygen concentration of 6.25% and boron nitride-doped graphene with a concentration of 12.5% display moderate adsorption energies, short recovery times, and favorable electronic responses. Notably, graphene oxide with a concentration of 6.25% exhibits band gap closure at the Fermi level following histamine adsorption. These results indicate that oxygen- and boron nitride-doped graphene monolayers with concentrations of 6.25% and 12.5%, respectively, are promising materials for histamine-sensing applications.