TAMRA-Amyloid-β (1-42) peptide is a fluorescently labeled peptide. Amyloid-β (1-42) (Aβ42) is a neurotoxic 42-residue protein fragment found in amyloid plaques in postmortem cerebral cortex from patients with Alzheimer's disease. Aggregation of Aβ42 results in the formation of neurotoxic fibrils or globular oligomers. TAMRA-Amyloid-β (1-42) peptide is a labeled form of Aβ42 containing carboxytetramethyl rhodamine (TAMRA), which displays excitation/emission maxima of 543/572 nm, respectively.