Table 1.

Characteristics of representative radiotracers

No.	Kd/Ki	Other targets	Scaffold	Status	Ref.
1	Kd = 4 nMa	Aβ, tau	Benzothiazole	in vitro	[81, 82]
2	Kd = 9.63 nMa	Aβ	Benzoxazole	in vivo	[83]
3	Kd = 148 nMa, Ki = 57.94 nMb,c	Aβ, tau	Phenothiazine	in vivo	[85, 86]
4	Ki = 66.2 nMc,d	Aβ, tau	Phenothiazine	in vivo	[87]
5	Ki = 19.9 nMc,d	Aβ, tau	Phenothiazine	in vivo	[87]
6	Kd = 8.9 nMa, Ki = 2 nMb,c	Aβ, tau	3-(benzylidine) indolin-2-one	in vitro	[88]
7	Kd = 5.4 nMa	Aβ	Chalcone	in vitro	[89]
8	Kd = 99.5 nMa,c	Aβ	Benzoimidazole	in vitro	[90]

^aDetermined by saturation binding assays

^bDetermined by ThT competition assays

^cIsotope unlabeled

^dDetermined by ¹²⁵I-SIL23 competition assays