Computational study of the RGD–peptide interactions with perovskite-type BFO-(111) membranes under aqueous conditions

Highlights: • Biocompatibilities of RGD are calculated on BFO-(1 1 1) membrane in the water environment. • Electronic conduction mechanism between RGD and BFO is explained in the AFM phase. • Effect of cationic salts is discussed on electronic and optical properties of RGD–BFO. We elucidated a number of facets regarding arginine–glycine–aspartate (RGD)–bismuth ferrite (BFO)-(1 1 1) membrane interactions and reactivity that have previously remained unexplored on a molecular level. Results demonstrate the intra-molecular interaction facilitates a "horseshoe" structure of RGD adsorbed onto the BFO-(1 1 1) membrane, through the electrostatic (Asp-cation-Fe) and water-bridge (OH₂O and H₂ONH₂) interactions. The effect of structural and electron-transfer interactions is attributed to the cation-valences, indicating that the divalent cations are electron-acceptors and the monovalent cations as electron-donors. Notably, the strongly bound Ca²⁺ ion exerts a "gluing" effect on the Asp-side-chain, indicating a tightly packed RGD–BFO configuration. Thus, modulating the biological response of BFO-(1 1 1) membrane will allow us to design more appropriate interfaces for implantable diagnostic and therapeutic perovskite-type micro-devices.