Cavity Lasing\nof Thioflavin T in the Condensed Phase\nfor Discrimination between Surface Interaction and β‑Sheet\nGroove Binding in Alzheimer-Linked Peptides

This study investigates the lasing effects in a Fabry–Perot\ncavity to discern the binding interactions of thioflavin T (ThT) with\nvarious peptides associated with Alzheimer’s disease, including\nAβ(1–42), KLVFFA, and diphenylalanine (FF) in the condensed\nphase. Utilizing kinetic lasing measurements, the research explores\nThT emission enhancements due to specific groove binding in β-sheet\nstructures and highlights additional contributions from weak surface\ninteractions and solvent–solute interactions. Lasing spectroscopy\nreveals a lack of transition of the FF system from its native state\nto an amyloid-like structure, challenging traditional ThT assay interpretations.\nThese findings show the potential of lasing spectroscopy in elucidating\nthe molecular basis of amyloid fibril formation and the development\nof diagnostic tools for amyloidogenic diseases.