Introducing Tb⁴⁺ in (Ce_0.09/Eu_0.96)Tb_0.92Mo_1.1O_6.93 Metal Oxide at Room Temperature and Its Use in Amyloid...

Tunable optical properties in nanomaterials enable a variety of applications in multidisciplinary areas. These properties are directly related to several different factors such as solvent conditions, synthesis methods, and most significantly, the oxidation states of metals participating in the absorption or emission properties. Lanthanide metals containing ABO₃ perovskites are among such nanomaterials that can be tuned to a great extent by only modifying the charged states on the metals in the composition. We report a green synthesis method through sonication to synthesize ABO₃ perovskites to incorporate Tb⁴⁺ into the perovskite composition at room temperature. The optical properties of the nanomaterial show emission in the entire ultraviolet-visible-near-infrared spectral regions through charge transfer between europium and terbium. The combination of cerium (C), molybdenum (M), europium (E), and terbium (T) results in a sheet-like CMET perovskite obeying hexagonal geometry. The nanomaterial is highly stable in an aqueous medium, showing finely suspended Tyndall effect due to particle size <300 nm. Owing to their wide range of emission behavior, surface charge, and aqueous stability, CMET perovskites were used to study the defibrillation of hen egg-white lysozyme (HEWL) as an amyloid model protein. The intrinsic property of the nanomaterial assists in the interaction of the fibrils with the perovskite and the emission range becomes the reporter of the defibrillation. Infrared spectroscopy shows the change in the material properties during the defibrillation. A preliminary test on the varying concentration of HEWL incubated with CMET perovskites shows linear behavior with R² = 0.9841. The tunable emission characteristic and aqueous stability of the perovskite material make it suitable for future biological applications.