Purity >98%. CRANAD 2 is a curcumin derivative and non-conjugated affinity probe for the detection of amyloid-Beta (ABeta) deposits in vitro and in vivo . It has high affinity for ABeta (Kd = 38 nM) and, when bound to ABeta aggregates, it exhibits a 70-fold increase in fluorescence intensity, a blue shift from 805 to 715 nm, and a large increase in quantum yield.