Patent ID: 8293782

Claim:
A A composition comprising a contrast agent for fluorescence imaging or photoacoustic imaging, the contrast agent comprising the compound represented by Formula (1) below, where n is 2; a is an integer of 1 to 3 and b is an integer of 3 and 5 to 10, or a is 4 and b is an integer of 3 and 6 to 10, or a is 5 and b is an integer of 1 to 10; where n is 3; a is an integer of 1 to 4 and b is an integer of 3 and 5 to 10, or a is 5 and b is an integer of 1 to 10; R 1 to R 8 each independently represent a hydrogen atom or a sulfonate that is any one of sodium sulfonate, potassium sulfonate, ammonium sulfonate, triethylammonium sulfonate, pyridinium sulfonate, lysine sulfonate, and arginine sulfonate; and R 9 to R 12 each independently represent a substituted or unsubstituted C1-C3 alkyl group.