Patent ID: 9675715
Date: 2017-06-13
CPC Classifications: A61K

Claim:
1. A contrast agent for photoacoustic imaging, comprising: a complex including albumin covalently bound to at least one organic dye that absorbs light in a near-infrared wavelength region, wherein the complex has a structure represented by formula (I): wherein, in the formula (I), A represents a site of the albumin with one amino group removed, A′ is an organic dye represented by formula (i) or formula (ii), and * in each of the formulae (i) and (ii) represents a bond with a nitrogen atom (N) in the formula (I), and wherein on average in the contrast agent, a number of molecules of the at least one organic dye covalently bound to the albumin of the complex is 1.6 or more: wherein, in the formulae (i) and (ii), Z's each represent a hydrogen atom, a sulfonic group, or a cyclic aromatic ring selected from the group consisting of a benz[e]indole ring, a benz[f]indole ring, and a benz[g]indole ring formed together with an indole ring bound to a corresponding one of Z's; and hydrogen atoms of the cyclic aromatic ring each may be replaced with an alkyl group having 1 to 10 carbon atoms, an alkoxy group having 1 to 10 carbon atoms, or a sulfonic group, wherein, in the formulae (i) and (ii), R wherein, in the formulae (i) and (ii), a's each represent an integer of 1 to 10; and n's each represent 2 or 3, and wherein, in the formula (ii), R