Kit and method for measuring measurement target substance in biological sample

A method for measuring a measurement target substance in a biological sample, the method comprising:

• a reaction step of reacting a biological sample with a labeled particle having a first binding substance capable of binding to a measurement target substance;
• a capturing step of capturing the labeled particle on a substrate having a second binding substance capable of binding to any one of the measurement target substance or the first binding substance by bringing a reaction product obtained in the reaction step into contact with the substrate;
• and
• a label information acquisition step of acquiring label information related to the measurement target substance,
• wherein the labeled particle is a luminescent labeled particle containing at least one kind of compound represented by Formula (1) and a particle,
• in the formula, R11 to R15 each independently represent a hydrogen atom, a halogen atom, an alkyl group, an aryl group, a heterocyclic group, an ethenyl group, an ethynyl group, an amino group, an acyl group, an alkoxy group, an aryloxy group, an alkylthio group, or an arylthio group, each of which may have a substituent, and at least three of R11, . . . , or R15 represent atoms or groups other than hydrogen atoms;
• X1 and X2 each independently represent a halogen atom, an alkyl group, an aryl group, a heterocyclic group, a hydroxy group, an alkoxy group, an aryloxy group, an alkylthio group, an arylthio group, an ethenyl group, or an ethynyl group, each of which may have a substituent, and X1 and X2 may be linked to each other to form a ring;
• Ar1 and Ar2 each independently represent an aryl group or a heterocyclic group, each of which may have a substituent;
• and L1 and L2 each independently represent any one of Formulae (L-1) to (L-4),
• in the formulae, R111 to R116 each independently represent a hydrogen atom, a halogen atom, an alkyl group, an aryl group, a heterocyclic group, an ethenyl group, an ethynyl group, an amino group, an acyl group, an alkoxy group, an aryloxy group, an alkylthio group, or an arylthio group, each of which may have a substituent;
• and A represents —O—, —S—, or —NH—.