Table 1.

Photophysical Properties^a of red-HyP-1 and Analogues

compd	λabs (nm)	λem (nm)	ε (M−1·cm−1)	Φb	fold PAc
red-HyP-1	760	798	5.4 × 104	0.043	1.00
1	796	813	1.72 × 105	0.122	2.42
2	759	791	1.57 × 105	0.195	2.26
3	789	822	1.35 × 105	0.054	2.36
4	757	803	7.95 × 104	0.047	1.00
5	759	785	9.05 × 104	0.195	0.99
6	782	818	8.92 × 104	0.061	1.24

^aCharacterized in CHCl₃.

^bFluorescence quantum yield (CHCl₃) relative to indocyanine green (ICG) (DMSO).

^cFold increase in PA signal relative to red-HyP-1.