Kit for detection/quantification of analyte, and method for detection/quantification of analyte

A kit for detecting a target substance, comprising:

• a first bound substance, wherein a first substance including a stimuli-responsive polymer binds to a first affinity substance having affinity to the target substance;
• and
• a second bound substance in which a second electrically charged substance binds to a second affinity substance having affinity to the target substance, wherein
• the first affinity substance and the second affinity substance can bind simultaneously to different sites of the target substance.

A method for quantifying a target substance in a sample, comprising steps of:

• mixing a first bound substance in which a first substance containing stimuli-responsive polymer binds to a first affinity substance having affinity to the target substance, a second bound substance in which a second electrically charged substance binds to a second affinity substance having affinity to the target substance, and a sample;
• putting the mixture under aggregation condition of the stimuli-responsive polymer, and measuring the turbidity of the mixture;
• and
• calculating the amount of a target substance in the sample based on a correlation equation between the amount of the target substance and the turbidity under the aggregation conditions.