A kit for measuring a substance to be measured, comprising: a compound represented by Formula that binds to a first binding substance capable of binding to the substance to be measured; and a substrate that includes, on a metal film, a detection region having a second binding substance capable of binding to any one of the substance to be measured or the first binding substance, in the formula, R 11,, and R 13 each represent an alkyl group, and these groups may have a substituent; R 12 represents a phenyl group, and this group may have a substituent; L 1 and L 2 each represent Formula (L-1); Ar 1, Ar 2, Ar 3, and Ar 4 each represent an aryl group, and these groups independently may have a substituent; and X 1 and X 2 each independently represent a halogen atom or an alkoxy group, and these groups may have a substituent, provided that at least one of R 11, R 12, R 13, Ar 1, Ar 2, Ar 3, Ar 4, X 1, or X 2 has a hydrophilic part, wherein the hydrophilic part has a polyethylene glycol structure, a betaine structure, an amino acid structure, or a sulfonic acid group, and at least one of R 11, R 12, R 13, Ar 1, Ar 2, Ar 3, Ar 4, X 1, or X 2 has a capture part capable of forming a covalent bond with a biological molecule, wherein the capture part is a carboxyl group, an active ester, an isothiocyanate, or a maleimide, and further wherein at least one of Ar 1 or Ar 2 in Formula is Formula (Ar-1), and at least one of Ar 3 or Ar 4 in Formula is Formula (Ar-1), in the formula, R 121 and R 122 each independently represent a halogen atom, an alkyl group, or an alkoxy group, provided that R 121 and R 122 each may have a hydrophilic part or a capture part capable of forming a covalent bond with a biological molecule, wherein the hydrophilic part has a polyethylene glycol structure, a betaine structure, an amino acid structure, or a sulfonic acid group, and wherein the capture part is a carboxyl group, an active ester, an isothiocyanate, or a maleimide, n represents an integer of 0 to 4, and in a case where n is 2 or more, a plurality of R 122 's may be the same or different from each other, the substituents being selected from the group consisting of a sulfamoyl group, a cyano group, an isocyano group, a thiocyanato group, an isothiocyanato group, a nitro group, a nitrosyl group, a halogen atom, a hydroxy group, an amino group, a mercapto group, an amide group, an alkoxy group, an aryloxy group, an alkylthio group, an arylthio group, a carbamoyl group, an acyl group, an aldehyde group, a carbonyl group, an aryl group, an alkyl group, an alkyl group substituted with a halogen atom, an ethenyl group, an ethynyl group, a silyl group and a trialkylsilyl group. a compound represented by Formula that binds to a first binding substance capable of binding to the substance to be measured; and a substrate that includes, on a metal film, a detection region having a second binding substance capable of binding to any one of the substance to be measured or the first binding substance, in the formula, R 11,, and R 13 each represent an alkyl group, and these groups may have a substituent; R 12 represents a phenyl group, and this group may have a substituent; L 1 and L 2 each represent Formula (L-1); Ar 1, Ar 2, Ar 3, and Ar 4 each represent an aryl group, and these groups independently may have a substituent; and X 1 and X 2 each independently represent a halogen atom or an alkoxy group, and these groups may have a substituent, provided that at least one of R 11, R 12, R 13, Ar 1, Ar 2, Ar 3, Ar 4, X 1, or X 2 has a hydrophilic part, wherein the hydrophilic part has a polyethylene glycol structure, a betaine structure, an amino acid structure, or a sulfonic acid group, and at least one of R 11, R 12, R 13, Ar 1, Ar 2, Ar 3, Ar 4, X 1, or X 2 has a capture part capable of forming a covalent bond with a biological molecule, wherein the capture part is a carboxyl group, an active ester, an isothiocyanate, or a maleimide, and further wherein at least one of Ar 1 or Ar 2 in Formula is Formula (Ar-1), and at least one of Ar 3 or Ar 4 in Formula is Formula (Ar-1), in the formula, R 121 and R 122 each independently represent a halogen atom, an alkyl group, or an alkoxy group, provided that R 121 and R 122 each may have a hydrophilic part or a capture part capable of forming a covalent bond with a biological molecule, wherein the hydrophilic part has a polyethylene glycol structure, a betaine structure, an amino acid structure, or a sulfonic acid group, and wherein the capture part is a carboxyl group, an active ester, an isothiocyanate, or a maleimide, n represents an integer of 0 to 4, and in a case where n is 2 or more, a plurality of R 122 's may be the same or different from each other, the substituents being selected from the group consisting of a sulfamoyl group, a cyano group, an isocyano group, a thiocyanato group, an isothiocyanato group, a nitro group, a nitrosyl group, a halogen atom, a hydroxy group, an amino group, a mercapto group, an amide group, an alkoxy group, an aryloxy group, an alkylthio group, an arylthio group, a carbamoyl group, an acyl group, an aldehyde group, a carbonyl group, an aryl group, an alkyl group, an alkyl group substituted with a halogen atom, an ethenyl group, an ethynyl group, a silyl group and a trialkylsilyl group.