Chrysamine G is a lipophilic, bis-salicylic acid analog of Congo Red that displays both high (Kd = 200 nM; Bmax = 1.13 moles per mole of Ab40) and low (Kd = 38.77 µ M; Bmax = 23.10 moles per mole of Ab40) affinity binding sites for beta-amyloid (Ab) fibrils.